UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a)

of the Securities Exchange Act of 1934

(Amendment No.     )

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ALLIANT ENERGY CORPORATION

(Name of Registrant as Specified in Its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

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NOTICE OF 2024 ANNUAL MEETING OF SHAREOWNERS OF ALLIANT ENERGY CORPORATION

DATE:	May 17, 2024
TIME:	9:00 a.m. CDT

www.virtualshareholdermeeting.com/LNT2024

VIRTUAL MEETING ONLY — NO PHYSICAL LOCATION

The virtual Annual Meeting may be accessed at www.virtualshareholdermeeting.com/LNT2024, where you will be able to listen to the meeting live, submit questions and vote online.

AGENDA:

1.    Elect six directors nominated by our Board of Directors to serve on our Board of Directors, one for a term expiring at the 2025 Annual Meeting of Shareowners, one for a term expiring at the 2026 Annual Meeting of Shareowners and four for terms expiring at the 2027 Annual Meeting of Shareowners

2.    Approve, on an advisory, non-binding basis, the compensation of our named executive officers

3.    Ratify the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for 2024

4.    Attend to any other business properly presented at this meeting

RECORD DATE: March 18, 2024

Shareowners of record of our common stock as of the close of business on March 18, 2024 will be entitled to notice of, and to vote at, the Annual Meeting.

PROXY VOTING: YOUR VOTE IS IMPORTANT. Whether or not you plan to participate in the Annual Meeting, please vote promptly.

You may vote your shares by telephone or online. Instructions for voting are on the enclosed proxy card. If you prefer, you may sign and date the enclosed proxy card and return it in the postage-paid envelope.

PARTICIPATING IN THE ANNUAL MEETING:

The 2024 Annual Meeting of Shareowners will be held exclusively online via live webcast. An audio broadcast of the Annual Meeting will also be available by telephone toll-free at (877) 346-6110. Shareowners of record as of the close of business on March 18, 2024, are entitled to participate in and submit questions in writing before and during the Annual Meeting by visiting  www.virtualshareholdermeeting.com/LNT2024. To participate in the online Annual Meeting, you will need the 16-digit control number included on your proxy card. The Annual Meeting will begin promptly at 9:00 a.m. CDT. Online check-in will begin at 8:45 a.m. CDT. Please allow ample time for the online check-in procedures.

ANNUAL REPORT:

A copy of our Annual Report for the fiscal year ended December 31, 2023 was included with these proxy materials.

Important Notice Regarding the Availability of Proxy Materials for the Shareowner Meeting to be held on May 17, 2024. The Alliant Energy Corporation Proxy Statement for the 2024 Annual Meeting of Shareowners and the Annual Report for the fiscal year ended December 31, 2023, are available at www.alliantenergy.com/eproxy.

By Order of the Board of Directors

John O. Larsen

Executive Chairman

Chairman of the Board

Dated, mailed and made available online on or before April 2, 2024.

In accordance with Securities and Exchange Commission rules, a notice containing instructions on how to access this proxy statement and our annual report online was mailed, starting on or about April 2, 2024, and we provided access to our materials online before that date to certain holders of our common stock on the close of business on the record date.

TABLE OF CONTENTS

Table of Contents 

Proxy Summary
Proposal One — Election of Directors	1
Corporate Governance	9
Meetings and Committees of the Board of Directors	13
2023 Director Compensation	18
Ownership of Voting Securities	20
Compensation Discussion and Analysis	22
Compensation and Personnel Committee Report	39
Summary Compensation Table	40
2023 Grants of Plan-Based Awards	43
2023 Outstanding Equity Awards at Fiscal Year-End	45
2023 Option Exercises and Stock Vested	47
2023 Pension Benefits	48
2023 Non-qualified Deferred Compensation	51
2023 Potential Payments Upon Termination or Change in Control	53
Pay for Performance	58
Proposal Two — Advisory Vote to Approve the Compensation of Our Named Executive Officers	61
Report of the Audit Committee	62
Fees Paid to Independent Registered Public Accounting Firm	63
Proposal Three — Ratification of the Appointment of Deloitte & Touche LLP as the Company’s Independent Registered Public Accounting Firm for 2024	64
Information About the Annual Meeting and Voting	65

PROXY SUMMARY

Proxy Summary

This summary highlights information contained in this Proxy Statement. It is only a summary. Please read the entire Proxy Statement and 2023 Annual Report before you vote.

2024 Annual Meeting of Shareowners

Date and Time: May 17, 2024 at 9:00 a.m. CDT

Record Date: March 18, 2024

Place: www.virtualshareholdermeeting.com/LNT2024

Voting Matters		Board Recommendation	Page
1.	Election of Six Director Nominees	FOR all Director Nominees	1
2.	Advisory Vote to Approve Executive Compensation	FOR	61
3.	Ratification of Appointment of Deloitte & Touche LLP as Independent Registered Public Accountants for 2024	FOR	64

Vote your proxy today in one of the following methods:

www.proxyvote.com	(800) 690-6903	Mark, sign and date your proxy card and return it in the postage-paid envelope provided. Your proxy card must be received by May 16, 2024. 401(k) participants’ cards must be received by May 13, 2024.
Vote your proxy online until 10:59 p.m. CDT on May 16, 2024. 401(k) participants’ votes must be received by May 13, 2024.	Vote your proxy using a touch-tone telephone until 10:59 p.m. CDT on May 16, 2024. 401(k) participants’ votes must be received by May 13, 2024.

If you vote your proxy online or by telephone, you do NOT need to mail back your proxy card.

See pages 65-69 for directions on voting your proxy and to see how your votes are counted.

ELECTION OF DIRECTORS

ALLIANT ENERGY | 2024 Proxy Statement | 1

ELECTION OF DIRECTORS

Proposal One—ELECTION OF DIRECTORS

At our annual meeting of shareowners (Annual Meeting), six directors will be elected. The nominees are:

Lisa M. Barton	Roger K. Newport
Ignacio A. Cortina	Christie Raymond
Stephanie L. Cox	Carol P. Sanders

Each nominee currently serves on our Board of Directors. If elected as directors, each of Ms. Barton, Ms. Cox, Mr. Newport and Ms. Sanders will serve until our Annual Meeting of Shareowners in 2027 or until his or her successor has been duly qualified and elected. Mr. Cortina, Ms. Raymond and Ms. Barton were added to the Board of Directors to fill vacancies since our 2023 Annual Meeting of Shareowners. In accordance with our Bylaws and Wisconsin law, when a director is appointed to fill a vacancy, his or her initial term expires at the next annual meeting of shareowners, regardless of the class to which the director is elected. If elected as a director, Ms. Raymond will serve until our Annual Meeting of Shareowners in 2025, Mr. Cortina will serve until our Annual Meeting of Shareowners in 2026, and, as stated above, Ms. Barton will serve until our Annual Meeting of Shareowners in 2027, or until their successors have been duly qualified and elected.

The nominees were selected by the Board of Directors on the recommendation of the Nominating and Governance Committee. The Nominating and Governance Committee is responsible for evaluating nominees for director and director candidates. The committee has criteria to ensure that the specific skills, qualifications and experiences necessary for the effectiveness of the Board of Directors are fully represented on the Board. In addition, the Nominating and Governance Committee strives to create a diverse Board of Directors as measured by the criteria of age, gender, ethnicity, race, tenure, skills, qualifications and experience. The following charts reflect the skills and qualifications and demographic information that the Board views as important when evaluating director nominees. Each director nominee also contributes other important skills, expertise, experience and personal attributes to the Board that are not reflected in the chart below.

ALLIANT ENERGY | 2024 Proxy Statement | 2

ELECTION OF DIRECTORS

The table below provides a summary of our Board diversity as of April 2, 2024.

Total Number of Directors	11
	Female	Male
Part I: Gender Identity
Directors	5	6
Part II: Demographic Background
Hispanic or Latin-x	0	2
White	5	4

The balance of tenure of our directors promotes experience and stability while also allowing for a broader understanding of the issues that can affect our business. Over the last five years, we have added five new independent directors to our Board. Our more tenured directors provide deep historical perspective of our Company and our industry and provide leadership to the Board. Our newer directors provide fresh perspectives and benefit from the knowledge and experience of our more tenured directors. This optimal combination of experience, subject matter expertise and fresh perspectives ensures that our Board is able to provide oversight and guidance that is innovative, balanced and aligned with the Company’s purpose and strategy.

Our Bylaws set a mandatory retirement age for directors to encourage Board refreshment, providing that a Director may not stand for election at an Annual Meeting of Shareowners after reaching age 70. The Bylaws do not provide any exceptions nor the ability to waive the mandatory retirement age.

ALLIANT ENERGY | 2024 Proxy Statement | 3

ELECTION OF DIRECTORS

In fulfilling its responsibility to identify qualified candidates for membership on the Board of Directors, the Nominating and Governance Committee considers, among other factors, the following attributes of all nominees:

•    Highest personal and professional ethics, integrity and values

•    Highly accomplished in his or her respective field, with superior credentials and recognition and broad experience at the administrative and/or policy-making level in business, government, education, technology or public interest

•    Ability to exercise sound business judgment

•    Independence from any particular constituency and/or ability to represent all of our shareowners and commitment to enhance long-term shareowner value

•    Relevant expertise and experience and the ability to offer advice and guidance to our Chief Executive Officer based on that expertise and experience

•    Sufficient time available to devote to activities of the Board of Directors and to enhance his or her knowledge of our business

The Nominating and Governance Committee regularly evaluates the composition of the Board in light of the Company’s strategy and the types of risks and opportunities associated with the strategy. The committee seeks to nominate directors that provide a mix of experience, knowledge and abilities in aggregate that enable the Board to fulfill its responsibilities.

Biographies of the director nominees and continuing directors follow. The biographies list the key qualifications, skills and experience of each director nominee and continuing director that led to the Board’s conclusion that the person should serve. Each nominee and continuing director’s age is as of April 2, 2024.

Directors will be elected by a majority of the votes cast at the meeting assuming a quorum is present. Any shares not voted at the meeting, including abstentions and broker non-votes, will not be counted as votes cast. The proxies solicited may be voted for a substitute nominee or nominees if any of the nominees is unable to serve, or for good reason will not serve, a contingency the Board of Directors does not currently anticipate.

Alliant Energy Corporation (Alliant Energy) is a public utility holding company whose wholly-owned regulated utility subsidiaries are Interstate Power and Light Company (IPL) and Wisconsin Power and Light Company (WPL). The members of our Board of Directors are identical to the members of the Boards of Directors of IPL and WPL. References to Company throughout this Proxy Statement refer to all three companies unless otherwise indicated.

Additional information regarding the selection process for members of the Board of Directors can be found starting on page 16.

þ The Board of Directors recommends a vote FOR the nominees for director.

ALLIANT ENERGY | 2024 Proxy Statement | 4

ELECTION OF DIRECTORS

NOMINEES FOR DIRECTOR

Summary: Ms. Barton brings extensive knowledge of the utility industry to the Board. Ms. Barton has served as President and Chief Executive Officer of Alliant Energy since January 2024. She has served as Chief Executive Officer of IPL and WPL since February 2023. She previously was President and Chief Operating Officer of Alliant Energy from February 2023 to January 2024. Prior to joining Alliant Energy, Ms. Barton served as Executive Vice President and Chief Operating Officer of American Electric Power Company, Inc. (AEP) from January 2021 to November 2022, Executive Vice President — Utilities of AEP from January 2020 to December 2020, and Executive Vice President — Transmission of AEP from 2011 to 2019. Ms. Barton has served on the Board of Directors of Commercial Metals Company, a manufacturer, recycler and marketer of steel and metal products, since 2020. She has been a Director of IPL and WPL since 2024. Skills and Qualifications: strategic leadership; financial acumen/literacy; operations; customer perspective; public policy and regulatory; human capital management; risk management; technology systems; environmental and safety.

Lisa M. Barton Age: 58 Director since: 2024 Nominated for a term expiring in: 2027 Committee memberships: • Equity Awards

Summary: Mr. Cortina brings to the Board extensive experience in public policy, compliance, corporate governance, environmental and legal matters. Mr. Cortina has been Executive Vice President, Chief Legal Officer and Secretary of Oshkosh Corporation, a leading innovator of mission-critical vehicles and essential equipment, since February 2023. Mr. Cortina previously served as Executive Vice President, General Counsel and Secretary from 2016 to 2023. He has held various roles of increasing responsibility since joining Oshkosh Corporation in 2003. He has been a Director of IPL and WPL since 2023. Skills and Qualifications: strategic leadership; financial acumen/literacy; public policy and regulatory; human capital management; risk management; environmental and safety.

Ignacio A. Cortina Age: 52 Director since: 2023 Nominated for a term expiring in: 2026 Committee memberships: • Compensation and Personnel •Operations

Summary: Ms. Cox brings to our Board more than 30 years of experience in the energy sector leading strategic planning, P&L management, human resources, manufacturing, supply chain and other functional roles for global organizations. Ms. Cox served as Executive President of Operations at John Wood Group PLC (Wood), a global leader in consulting and engineering in energy and materials markets, from October 2020 through July 2022. She also served as Wood’s Chief Executive Officer of Asset Solutions for the Americas from October 2019 to October 2020. Prior to joining Wood, Ms. Cox held multiple executive leadership roles with Schlumberger Limited (SLB), a global technology company that drives energy innovation for a balanced planet, spanning a 28-year career, including President, North America Land Drilling from 2018-2019; Vice President, Human Resources from 2017-2018 and from 2009-2014; President, North America from 2016-2017; President, Asia from 2014-2016; and leadership positions overseeing IT, Human Resources, Manufacturing and Supply Chain. Ms. Cox has served on the Board of Directors of Technip Energies, N.V., an engineering and technology company for the energy transition with shares listed on Euronext Paris, since 2023. She has served as a Director of IPL and WPL since 2023. Skills and Qualifications: strategic leadership; financial acumen/literacy; operations; customer perspective; human capital management; risk management; technology systems; environmental and safety.

Stephanie L. Cox Age: 55 Director since: 2023 Nominated for a term expiring in: 2027 Committee memberships: • Compensation and Personnel • Operations

ALLIANT ENERGY | 2024 Proxy Statement | 5

ELECTION OF DIRECTORS

Summary: Mr. Newport brings to our Board broad experience and leadership in finance and operations of a manufacturing company. He served as Chief Executive Officer and a Director of AK Steel Holding Corporation from January 2016 until March 2020, when he retired in connection with the acquisition of AK Steel by Cleveland-Cliffs Inc. Prior to that, Mr. Newport served at AK Steel Holding Corporation as Executive Vice President, Finance and Chief Financial Officer since May 2015, as Senior Vice President, Finance and Chief Financial Officer since May 2014, and as Vice President, Finance and Chief Financial Officer since May 2012. Prior to that, Mr. Newport served in a variety of other leadership positions since joining AK Steel in 1985, including Vice President-Business Planning and Development, Controller and Chief Accounting Officer, Assistant Treasurer, Investor Relations, Manager-Financial Planning and Analysis and Product Manager. Mr. Newport has served on the Board of American Financial Group, Inc., an insurance holding company, since 2024. He has been a Director of IPL and WPL since 2018. Skills and Qualifications: strategic leadership; financial acumen/literacy; operations; customer perspective; public policy and regulatory; human capital management; risk management; technology systems; environmental and safety.

Roger K. Newport Age: 59 Director since: 2018 Nominated for a term expiring in: 2027 Committee memberships: • Audit • Nominating and Governance

Summary: Ms. Raymond brings extensive customer-focused marketing experience to our Board. Ms. Raymond has served as Senior Executive Vice President and Chief Marketing Officer at Kohl’s, a leading retailer, since August 2022. In her current role, she is responsible for Kohl’s marketing and customer service organizations, including the overall marketing strategy, brand and creative, media and personalization, credit and loyalty, customer insights and analytics, corporate communications, and philanthropic efforts. Prior to her current role, she was Executive Vice President Customer Engagement, Analytics & Insights from June 2020 to August 2022 and Senior Vice President, Media and Personalization from October 2017 to June 2020 at Kohl’s. Prior to joining Kohl’s, Ms. Raymond served in marketing, new business, and strategic planning leadership roles at The Walt Disney Company, where she had extensive experience with customer analytics and digital marketing, and Aspen Club Technologies. She has been a director of IPL and WPL since 2024. Skills and Qualifications: strategic leadership; financial acumen/literacy; customer perspective; risk management; technology systems.

Christie Raymond Age: 54 Director since: 2024 Nominated for a term expiring in: 2025 Committee memberships: • Audit • Compensation and Personnel

Summary: Ms. Sanders is our Lead Independent Director and brings valuable leadership and insights as an experienced leader of our Board. Ms. Sanders has been the President of Carol P. Sanders Consulting LLC since 2015, a business consulting firm serving insurance and technology clients. She served as the Executive Vice President, Chief Financial Officer and Treasurer of Sentry Insurance, a Mutual Company, located in Stevens Point, Wisconsin from 2013 to 2015. Previously, she served as the Executive Vice President and Chief Operating Officer of Jewelers Mutual Insurance Company from 2012 until 2013, where she also served as Senior Vice President, Chief Financial Officer and Treasurer from 2011 until 2012 and as Chief Financial Officer from 2004 until 2011. Before that, Ms. Sanders served as Controller and Assistant Treasurer of Sentry Insurance from 2001 to 2004. She has served on the Boards of Directors of RenaissanceRE Holdings Ltd., a global provider of reinsurance and insurance since 2016, and First Business Financial Services, Inc., a Wisconsin-based bank holding company since 2016. She has served as a Director of IPL and WPL since 2005. Skills and Qualifications: strategic leadership; financial acumen/literacy; operations; public policy and regulatory; human capital management; risk management; technology systems.

Carol P. Sanders Age: 57 Director since: 2005 Nominated for a term expiring in: 2027 Lead Independent Director Committee memberships: • Audit • Executive • Nominating and Governance (Chair)

ALLIANT ENERGY | 2024 Proxy Statement | 6

ELECTION OF DIRECTORS

CONTINUING DIRECTORS

Summary: Mr. Allen brings to our Board extensive experience in financial leadership. Mr. Allen served as Chief Financial Officer at Collins Aerospace since 2018 prior to retiring in 2020. He served as Senior Vice President and Chief Financial Officer at Rockwell Collins, Inc. in Cedar Rapids, Iowa, leading the company’s finance activities, including financial planning, accounting, treasury, audit, and tax from 2005 to 2018. Mr. Allen previously served in various financial officer positions at Rockwell Collins and its subsidiaries since 2001. Before joining Rockwell Collins, he served in various roles at Rockwell International, including Vice President and Treasurer, Vice President of Financial Planning, and Assistant Controller. Prior to that, he worked as an auditor at Deloitte & Touche and has passed the certified public accountancy examination. Mr. Allen has served on the Board of Triumph Group, Inc., an aerospace company, since 2023. Mr. Allen has been a Director of IPL and WPL since 2011. Skills and Qualifications: strategic leadership; financial acumen/literacy; public policy and regulatory; human capital management; risk management; technology systems; environmental and safety.

Patrick E. Allen Age: 59 Director since: 2011 Term expires in: 2026 Committee memberships: • Compensation and Personnel (Chair) • Executive • Nominating and Governance

Summary: Ms. Falotico brings to our Board more than 33 years’ experience across a diverse set of areas including business leadership, corporate governance, strategic planning, regulatory banking, marketing and sales, enterprise risk management, global operations and business transformations. Ms. Falotico served as President of Lincoln Motor Company from March 2018 until she retired in December 2022. She also served as Ford Motor Company’s Chief Marketing Officer from March 2018 until January 2021 and was a Group Vice President of Ford Motor Company since 2016. Ms. Falotico was named an Executive Vice President of Ford Motor Credit Company, a leading global automotive financial services provider, in 2012. In 2016 she was named Chief Operating Officer and moved rapidly into the role of Chair and CEO, serving as CEO until 2018 and Chair until 2019. She served as a Director of Ford Motor Credit Company until 2022. She has been a Director of IPL and WPL since 2021. Skills and Qualifications: strategic leadership; financial acumen/literacy; operations; customer perspective; public policy and regulatory; human capital management; risk management; technology systems; environmental and safety.

N. Joy Falotico Age: 56 Director since: 2021 Term expires in: 2025 Committee memberships: • Audit (Chair) • Executive • Operations

Summary: Mr. Garcia brings to our Board extensive operational leadership in heavy industrial industries. Mr. Garcia has been the Chief Executive Officer with Algoma Steel Group Inc., since June 2022. Mr. Garcia was President of the Pulp and Paper Division of Domtar Corporation from April 2014 to January 2021. Prior to joining Domtar, Mr. Garcia was the Chief Executive Officer at EVRAZ Highveld Steel & Vanadium Co., in South Africa. Mr. Garcia has more than 25 years of international management experience in paper, steel, and aluminum manufacturing and marketing. Mr. Garcia has served on the Board of Directors of Algoma Steel Group Inc., since June 2022. He has been a Director of IPL and WPL since 2020. Skills and Qualifications: strategic leadership; financial acumen/literacy; operations; customer perspective; public policy and regulatory; human capital management; risk management; technology systems; environmental and safety.

Michael D. Garcia Age: 59 Director since: 2020 Term expires in: 2026 Committee memberships: • Compensation and Personnel • Executive • Operations (Chair)

ALLIANT ENERGY | 2024 Proxy Statement | 7

ELECTION OF DIRECTORS

Summary: Mr. Larsen brings to our Board an extensive knowledge of the utility business and his tenure with the Company in strategic leadership positions. He currently serves as Executive Chairman and Chairman of the Board of Alliant Energy, IPL and WPL. He served as Chairman and Chief Executive Officer of Alliant Energy from February 2023 to January 2024 and Chairman, President and Chief Executive Officer from July 2019 to February 2023. He served as Chairman of the Board of IPL and WPL from February 2023 to January 2024 and as Chief Executive Officer of IPL and WPL from January 2019 to February 2023. Mr. Larsen previously served as President and Chief Operating Officer of Alliant Energy since January 2019, President of Alliant Energy since January 2018, Senior Vice President of Alliant Energy from 2014 to 2017, Senior Vice President of IPL from 2014 to 2018, and as Senior Vice President-Generation of Alliant Energy and IPL from 2010 to 2014. He served as President of WPL from 2010 to 2018. Mr. Larsen joined Alliant Energy in 1988 as an engineer and held engineering, energy delivery and generation roles of increasing importance with the Company. He has been a Director of IPL and WPL since 2019. Skills and Qualifications: strategic leadership; financial acumen/literacy; operations; customer perspective; public policy and regulatory; human capital management; risk management; technology systems; environmental and safety.

John O. Larsen Age: 60 Director since: 2019 Term expires in: 2025 Executive Chairman Chairman of the Board Committee memberships: • Executive (non-voting Chair)

Summary: Mr. O’Toole brings to our Board his strong experience in revenue strategy, customer strategy, data-driven business and digital commerce. Since 2023, Mr. O’Toole has been Associate Dean, Executive Programs and Clinical Professor of Marketing at the Kellogg School of Management of Northwestern University. From 2020 to 2023, Mr. O'Toole was Associate Dean, Executive Education and Clinical Professor of Marketing at Kellogg. From 2018 to 2020, Mr. O’Toole was the Executive Director of the Program for Data Analytics and Clinical Professor of Marketing at Kellogg. From 2016 to 2018, he was Senior Fellow and Clinical Professor of Marketing at Kellogg. He is the principal of O’Toole Associates, LLC, through which he serves as a Senior Advisor with McKinsey & Co., a global management consulting firm. Until his retirement in late 2016, Mr. O’Toole was Chief Marketing Officer and Senior Vice President of United Airlines and President, MileagePlus of United Continental Holdings, Inc., a global air carrier. He joined United in 2010 as Chief Marketing Officer and Senior Vice President and held positions with United as Senior Vice President, Marketing and Loyalty and President, MileagePlus from 2012 to 2014, Chief Operating Officer, MileagePlus from 2010 to 2012, and Chief Marketing Officer in 2010. Before joining United, Mr. O’Toole held leadership roles for over 13 years with Hyatt Hotels Corporation, including as Chief Marketing Officer and Chief Information Officer. He served on the Boards of Directors of LSC Communications, Inc., a print, print-related services and office products company, from 2016 to 2021, and Extended Stay America Inc., a hotel owner and operator, from 2017 to 2021. He has served as a Director of IPL and WPL since 2015. Skills and Qualifications: strategic leadership; financial acumen/literacy; operations; customer perspective; technology systems.

Thomas F. O’Toole Age: 66 Director since: 2015 Term expires in: 2025 Committee memberships: • Nominating and Governance • Operations

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CORPORATE GOVERNANCE

CORPORATE GOVERNANCE

Corporate Purpose and Values

Our purpose at Alliant Energy is to serve customers and build strong communities. Our purpose, supported by our values, is the foundation of our culture, guides our actions, and describes how we accomplish our strategy.

Ethical and Legal Compliance Policy

Our Board of Directors has adopted a Code of Conduct that serves as our code of ethics. We created our Code of Conduct to define our standards for workplace behavior and to provide guidance on what to do in difficult situations and gray areas. These guidelines apply to all employees, at every level, including our Chief Executive Officer (CEO), Chief Financial Officer (CFO), and Chief Accounting Officer, as well as the members of our Board of Directors. The expectations laid out in the Code of Conduct are quite simple: make good choices and live our values. Our Code of Conduct is posted at www.alliantenergy.com/investors under the Corporate Governance link. To comply with the disclosure requirements under Item 5.05 of Form 8-K, we will post any new amendments, other than technical, administrative, or other non-substantive amendments, to, or waivers from our Code of Conduct granted to our CEO, CFO, or Chief Accounting Officer on that website throughout the year.

Corporate Governance Guidelines

Our Board of Directors has adopted Corporate Governance Guidelines that outline how directors can represent investor interests and oversee how the Company fulfills its purpose. The Corporate Governance Guidelines, in conjunction with the Board committee charters, establish processes and procedures to help ensure effective and responsive governance by the Board. Our Corporate Governance Guidelines are posted at www.alliantenergy.com/investors under the Corporate Governance link.

Director Independence

Our Corporate Governance Guidelines provide that at least 75% of the members of the Board of Directors must be independent directors under the applicable rules of The Nasdaq Stock Market LLC (Nasdaq). The Audit, Compensation and Personnel, and Nominating and Governance Committees must be composed only of independent directors.

The Board of Directors evaluates directors’ independence under the applicable Nasdaq rules, including the categorical standards of independence provided by Nasdaq rules. The Board of Directors also considers certain other factors to determine a director’s independence.

The Board of Directors adopted resolutions that affirm that each of Mr. Allen, Mr. Cortina, Ms. Cox, Ms. Falotico, Mr. Garcia, Mr. Newport, Mr. O’Toole, Ms. Raymond, Ms. Sanders, and Mr. Oestreich, Ms. McAllister and Ms. Whiting while they were members of the Board of Directors, has no material relationship with the Company that would impair his or her independent judgment as a director and, therefore, is independent in accordance with Nasdaq rules.

Majority Voting in Uncontested Director Elections

Under our Bylaws, if a director nominee in an uncontested election (i.e., an election where the number of nominees is not greater than the number of directors to be elected) receives more AGAINST votes than FOR votes, the director nominee is required to offer his or her resignation to the Chair of the Board of Directors following certification of the shareowner vote. The Nominating and Governance Committee will consider such resignation and make a recommendation to the Board whether to accept or reject the tendered resignation, or whether other action should be taken. The Board will act on the tendered resignation, taking into account the Nominating and Governance Committee’s recommendation and all other factors deemed relevant, and publicly disclose (by a press release, a filing

ALLIANT ENERGY | 2024 Proxy Statement | 9

CORPORATE GOVERNANCE

with the SEC or other broadly disseminated means of communication) its decision regarding the tendered resignation within 90 days from the date of final certification of the shareowner vote. The director who has tendered a resignation pursuant to this provision will not participate in the Nominating and Governance Committee’s or the Board’s deliberations or decision with respect to the tendered resignation.

Attendance and Performance Evaluations

Our Board of Directors held eight joint (Alliant Energy, IPL and WPL) Board meetings in 2023. Each director attended at least 75% of the aggregate number of meetings of the Board of Directors and Board committees on which he or she served during his or her tenure on the Board.

The Board of Directors and each Board committee conduct performance evaluations annually to determine their effectiveness and suggest improvements. In addition, the Compensation and Personnel Committee evaluates the performance of the CEO on an annual basis.

Members of our Board of Directors are expected to attend our Annual Meeting of Shareowners. All members of our Board of Directors at the time of the 2023 Annual Meeting were present for the 2023 Annual Meeting.

Related-Person Transactions

We have adopted a written policy regarding related-person transactions. The policy provides that we will annually disclose information regarding related-person transactions as required by regulations of the SEC to be disclosed, or incorporated by reference, in our Annual Report on Form 10-K. For purposes of the policy “related-person” means any of our directors or executive officers, nominees for director and any member of the immediate family of such person.

A related-person transaction is generally a transaction in which: (1) we are a participant; (2) the amount involved exceeds $120,000; and (3) a related-person has a direct or indirect material interest. A related-person transaction does not include:

•    The payment of compensation by us to our executive officers, directors or nominees for director

•    A transaction in which the interest of the related-person arises solely from the ownership of our shares and all shareowners receive the same benefit on a pro-rata basis

•    A transaction in which the rates or charges involved are determined by competitive bids, or that involves the rendering of services as a common or contract carrier or public utility at rates or charges fixed and in conformity with law or governmental authority

•    A transaction that involves services as a bank, transfer agent, registrar, trustee under a trust indenture, or similar services

Furthermore, a related-person is not deemed to have a material interest in a transaction if the person’s interest arises only:

•From the person’s position as a director of another party to the transaction

•From the ownership by such person and all other related-persons, in the aggregate, of less than a 10% equity interest in another entity (other than a partnership) that is a party to the transaction

•From such person’s position as a limited partner in a partnership in which such person and other related-persons have an interest of less than 10%, and the person is not a general partner of, and does not hold another position in, the partnership

•From both such director position and ownership interest

Pursuant to the policy, each of our executive officers, directors and nominees for director is required to disclose to the Nominating and Governance Committee certain information regarding related-person transactions for review, approval or ratification by the committee. If possible, they should disclose the related-person transaction to the committee before the related-person transaction occurs. In any event, they must disclose the transaction as soon as practicable after the transaction is effected or they become aware of it.

The Nominating and Governance Committee will decide whether to approve or ratify the related-person transaction based on whether the transaction is contrary to the best interests of the Company. The committee may take into account the effect of a director’s related-person transaction on such person’s status as an independent member of our Board of Directors and eligibility to serve on Board committees under Securities and Exchange Commission (SEC) and Nasdaq rules.

We had no related-person transactions since the beginning of 2023, and no related-person transactions are currently proposed.

Risk Oversight

Our Corporate Governance Guidelines provide that the Board of Directors is responsible for overseeing and understanding our purpose, vision and mission, strategic plans, overall corporate risk profile, risk parameters, annual operating plans and annual budgets, and for monitoring whether these plans are being implemented effectively. We utilize an enterprise risk management (ERM) program, which is designed to identify, assess, communicate and manage material risks in a structured framework. Under the ERM program, management periodically reviews an extensive risk inventory and assigns values and rankings to identify key risks, and identifies mitigation strategies for key risks. The Audit Committee oversees the ERM program. Risks identified under the ERM program are overseen by the Board or a designated Board committee and certain members of management, and internal audit assessments of such risks are periodically completed as needed. In addition, the Executive Review and Risk Committee, composed of senior executives, reviews business, financial, reputational, and operational risks that may be material to the Company, as well as processes to control, mitigate and monitor the risks, including risks identified through the ERM program.

ALLIANT ENERGY | 2024 Proxy Statement | 10

CORPORATE GOVERNANCE

The process assigns oversight of certain risks to the Board of Directors or certain Board committees. Significant operational risks are the subject of regularly scheduled reports to the full Board of Directors or the appropriate Board committee. Certain risks covered in 2023 are as follows.

Board of Directors Cybersecurity Regulatory	Nominating and Governance Committee Corporate Governance Corporate Environmental and Social Responsibility		Compensation and Personnel Committee Compensation Workforce Corporate Culture
Audit Committee Financial Performance and Reporting Compliance Liquidity		Operations Committee Safety Environmental Compliance Customer Satisfaction Large Construction Operations Physical Security Price and Volume of Commodities, Materials and Supplies Catastrophic Events

The Compensation and Personnel Committee conducted an assessment of our compensation policies and practices in 2023. The result of this assessment is described in further detail under “Compensation and Personnel Committee Risk Assessment” in the Compensation Discussion and Analysis.

Corporate Sustainability, Environmental and Social Responsibility Oversight

We recognize the importance that sustainability, environmental and social responsibility have on our operations. These matters are represented by our Company purpose and values. The Nominating and Governance Committee is responsible for general oversight of these issues, including review and approval of our annual Corporate Responsibility Report. The committee oversees the Company’s progress on important sustainability topics, which include a broad range of issues handled by various committees. The Board of Directors and Board committees covered sustainability responsibilities in 2023 as follows.

Board of Directors Purpose, Mission and Strategy Cyber and Physical Security Public Policy Engagement	Nominating and Governance Committee ESG Oversight Board and Management Quality Board Structure Ownership and Shareowner Rights Corporate Responsibility Report Political Engagement		Compensation and Personnel Committee Remuneration and ESG Performance Metrics Diversity, Equity and Inclusion Workforce Environment Corporate Culture Workforce Development
Audit Committee Audit and Financial Reporting Enterprise Risk Management Code of Conduct Conflict of Interest Business Ethics		Operations Committee Climate Change Risks Greenhouse Gas Emissions Water Management Energy Portfolio Diversity Emissions and Waste Community Relations Customer Engagement Safety and Health Supply Chain Energy Reliability and Resiliency

Shareowner Outreach

In 2023, we reached out to holders of approximately 55% of our outstanding shares, and held discussions with those who agreed to meet. Our outreach meetings generally included discussions about governance, executive compensation, sustainability, our clean energy vision, human capital management and diversity, equity and inclusion matters, and board risk oversight. The Executive Chairman, Lead Independent Director, CEO, Treasurer, and members of the Environmental Services & Corporate Sustainability, Corporate Secretary, Legal and Investor Relations departments participated in these discussions. Shareowner feedback and suggestions that we received were reported to the Board of Directors or relevant Board committee for consideration.

In addition, our top managers, including the Executive Chairman, CEO and CFO, regularly participate in investor and industry conferences throughout the year to discuss performance and share perspectives on Company and industry developments. We also offer channels for shareowners to contact the Board of Directors with any inquiry or issue.

ALLIANT ENERGY | 2024 Proxy Statement | 11

CORPORATE GOVERNANCE

Communication with Directors

Shareowners and other interested parties may communicate with the full Board of Directors, non-employee directors as a group, or individual directors (including the Lead Independent Director) by writing to our Corporate Secretary, who will post such communication directly to our Board of Directors’ confidential web portal.

Board of Directors Leadership Structure

Our Bylaws and our Corporate Governance Guidelines provide that the Board of Directors is responsible for selecting a Chair of the Board of Directors and a CEO. The Board regularly reviews the leadership structure. As part of the Company’s recent CEO succession planning process, the Board determined that having Mr. Larsen serve as Executive Chairman and Chairman of the Board and Ms. Barton serve as President and CEO provides the optimal leadership structure at this time. This structure leverages Mr. Larsen’s company and industry knowledge and strong stakeholder relationships to support a successful transition.

Mr. Larsen is well-suited to lead the Board due to his extensive company and industry expertise and experience, and his strong relationships with external stakeholders. This experience is valuable to the Board in its oversight, advisory and risk management roles. Mr. Larsen also provides support to the CEO on strategic matters, external stakeholder relationships, and general support and counsel during the transition. Separating the CEO role allows Ms. Barton to focus on leading all aspects of the Company’s strategy development and execution, including operational, financial, regulatory, workforce, and public policy matters.

The Board continues to have a strong Lead Independent Director. As the Chair of the Nominating and Governance Committee, Ms. Sanders is currently designated as the Lead Independent Director. The Lead Independent Director is recognized by management and the Board of Directors as a key position of leadership within the Board of Directors. Our Corporate Governance Guidelines provide that the Lead Independent Director will preside at regular executive sessions of the Board of Directors, without management participation, though our Corporate Governance Guidelines do not grant the Lead Independent Director any special authority over management. Our Lead Independent Director’s role also encompasses additional Board governance responsibilities.

Lead Independent Director Roles

• Communicating applicable information from executive session deliberations to the Executive Chairman and CEO

• Reviewing with the Executive Chairman and CEO items of importance for consideration by the Board of Directors

• Acting as principal liaison between the independent directors and management on sensitive issues

• Discussing with the Executive Chairman and CEO important issues to assess and evaluate views of the Board of Directors

• Consulting with any or all of our independent directors at the discretion of either party and with or without the attendance of the Executive Chairman and CEO

• In conjunction with the Nominating and Governance Committee, recommending to the Executive Chairman the membership of the various Board committees and selection of the Board committee chairs

• In conjunction with the Nominating and Governance Committee, interviewing all director candidates and making recommendations to the Board of Directors on director nominees

• Mentoring and counseling new members of the Board of Directors to assist them in becoming active and effective directors

• In conjunction with the Nominating and Governance Committee, reviewing and approving the philosophy of, and program for, compensation of the independent directors

• Meeting with the CEO to discuss the CEO performance evaluation

We believe that the use of a Lead Independent Director has been effective for us and has greatly facilitated communication of important issues between the independent members of the Board of Directors and the Executive Chairman and CEO.

The Board of Directors regularly reviews the leadership structure considering a variety of factors to implement a leadership structure it believes is in the best interests of the Company, its customers and and its shareowners. The Board of Directors recognizes that, depending on the specific characteristics and circumstances of the Company, other Board leadership structures might also be appropriate.

Other Board Service

Our Corporate Governance Guidelines provide that a director who is expected to be elected or appointed to an additional board of directors of a public company shall provide notice to the Board Chair and Lead Independent Director prior to accepting such additional directorship. This requirement allows the Board Chair and Lead Independent Director to evaluate for any potential conflicts, whether the directors will continue to have sufficient time available to devote to the activities of the Board of Directors, and any other considerations related to fulfilling their responsibilities to our shareowners.

Executive Sessions

The independent directors meet in executive session with no member of our management present at every regular meeting of the Board of Directors.

ALLIANT ENERGY | 2024 Proxy Statement | 12

MEETINGS AND COMMITTEES OF THE BOARD OF DIRECTORS

MEETINGS AND COMMITTEES OF THE BOARD OF DIRECTORS

The Board of Directors has five standing committees: (1) Audit; (2) Compensation and Personnel; (3) Nominating and Governance; (4) Operations; and (5) Executive. The Board of Directors has adopted formal written charters for each of the standing committees, which are posted at www.alliantenergy.com/investors under the Corporate Governance link. The Board of Directors also has established an Equity Awards Committee, which has the authority to approve certain limited equity issuances to employees other than executive officers. Directors serve on the following standing committees:

	Audit	Compensation and Personnel	Nominating and Governance	Operations	Executive
Patrick E. Allen		C	ü		ü
Lisa M. Barton
Ignacio A. Cortina		ü		ü
Stephanie L. Cox		ü		ü
N. Joy Falotico	C			ü	ü
Michael D. Garcia		ü		C	ü
John O. Larsen					C*
Roger K. Newport	ü		ü
Thomas F. O’Toole			ü	ü
Christie Raymond	ü	ü
Carol P. Sanders	ü		C		ü

C = Committee Chair        C* = Non-Voting Committee Chair        ü= Member

Each committee is described below. The committees of our Board of Directors, including the composition and independence of the committees, are identical to the committees of the Board of Directors of IPL and WPL. The term “joint meetings” in the following descriptions refers to meetings of the Company, IPL and WPL. Except as otherwise noted, all meetings were held jointly.

ALLIANT ENERGY | 2024 Proxy Statement | 13

MEETINGS AND COMMITTEES OF THE BOARD OF DIRECTORS

Audit Committee
Members	N. Joy Falotico, Chair Roger K. Newport Christie Raymond (effective April 1, 2024) Carol P. Sanders
Independence and Financial Expertise	All members are independent as required by applicable SEC and Nasdaq rules. The Board of Directors has determined that Ms. Falotico, Mr. Newport and Ms. Sanders are audit committee financial experts and all committee members are financially sophisticated within the meaning of Nasdaq rules.
Meetings	The committee held six meetings in 2023.
Charter	The committee charter is posted at www.alliantenergy.com/investors under the Corporate Governance link.
Responsibilities	The primary responsibilities of the Audit Committee are:
	•	Engaging and overseeing the Company’s independent auditors (taking into account the vote on shareowner ratification), considering the qualifications, performance and independence of the independent auditors, periodically reviewing and evaluating the lead audit partner of the independent auditors and periodically considering whether to rotate the independent auditors
	•	Pre-approving all audit engagement services and permitted non-audit services to be performed by the independent auditors
	•	Reporting to the Board of Directors on the quality and integrity of the Company’s financial statements and its related internal controls over financial reporting, and reviewing with management and the independent auditors: (1) the Company’s annual and quarterly financial statements and other financial disclosures, including earnings press releases and earnings guidance; and (2) major issues as to the adequacy of the Company’s internal control over financial reporting
	•	Reviewing with the independent auditors and the Company’s internal auditors the overall scope and plans for their respective audits
	•	Preparing the Report of the Audit Committee for inclusion in the Company’s proxy statement
	•	Reviewing and assessing the guidelines and policies governing the Company’s risk management processes, the Company’s major financial risk exposures and actions taken to monitor and control such risk exposures
	•	Overseeing compliance and ethical standards adopted by the Company
	•	Reviewing the status of the Company’s compliance with laws, regulations and internal procedures, and monitoring contingent liabilities and risks that may be material to the Company
	•	Establishing procedures for the Company to receive, retain and respond to the confidential, anonymous submission of concerns regarding accounting and auditing matters or other federal securities law matters
	Additional information on oversight roles and responsibilities of the Audit Committee is provided on page 11.

ALLIANT ENERGY | 2024 Proxy Statement | 14

MEETINGS AND COMMITTEES OF THE BOARD OF DIRECTORS

Compensation and Personnel Committee
Members	Patrick E. Allen, Chair Ignacio A. Cortina Stephanie L. Cox Michael D. Garcia Christie Raymond (effective April 1, 2024)
Independence	All members are independent as required by applicable SEC and Nasdaq rules.
Meetings	The committee held seven meetings in 2023.
Charter	The committee charter is posted at www.alliantenergy.com/investors under the Corporate Governance link.
Responsibilities	The primary responsibilities of the Compensation and Personnel Committee are:
	•	Overseeing compensation philosophy and policies relating to compensation of the Company’s executive officers
	•	Setting corporate goals and objectives relevant to CEO and executive compensation and evaluating the CEO’s performance compared to those goals
	•	Determining and approving the CEO’s compensation and benefits based on the CEO’s performance
	•	Reviewing and approving the compensation of the other executive officers
	•	Reviewing and approving stock ownership guidelines
	•	Overseeing the general health of the Company’s working environment and how the Company is addressing any related trends
	•	Reviewing the Compensation Discussion and Analysis and producing a Compensation and Personnel Committee Report for inclusion in the Company’s proxy statement
	•	Evaluating its relationship with any compensation consultant for any conflicts of interest and assessing the independence of any of its legal, compensation or other external advisors
	Additional information on the roles and responsibilities of the Compensation and Personnel Committee is provided on page 11 and in the Compensation Discussion and Analysis beginning on page 22.

Compensation Advisor

The Compensation and Personnel Committee has engaged Pay Governance LLC as its independent external advisor to analyze the competitive level of executive compensation and provide information regarding executive compensation trends. The committee reviewed its relationship with Pay Governance and considered Pay Governance’s independence and the existence of potential conflicts of interest. The committee determined that the engagement of Pay Governance did not raise any conflict of interest or other issues that would adversely impact Pay Governance’s independence. In reaching this conclusion, the committee considered various factors, including:

•Whether Pay Governance and its advisors provide other services to us

•The amount of fees we pay to Pay Governance as a percentage of Pay Governance’s total revenues

•The policies and procedures that Pay Governance has implemented to prevent conflicts of interest

•Any business or personal relationship of an individual Pay Governance advisor working with us or with a member of the committee

•Any of our stock owned by the individual Pay Governance advisor working with us

•Any business or personal relationships between our executive officers and Pay Governance or the Pay Governance advisor working with us

Delegation

The Board of Directors has delegated to the Equity Awards Committee the authority to approve certain limited equity issuances to employees other than executive officers. Ms. Barton is the sole member of this committee.

Compensation and Personnel Committee Interlocks and Insider Participation

No person who served as a member of the Compensation and Personnel Committee during 2023: (a) served as one of our officers or employees or (b) has any relationship requiring disclosure as a related-person transaction under Item 404 of the SEC Regulation S-K. None of our executive officers serves as a member of the Board of Directors or compensation committee of any other company that has an executive officer serving as a member of our Board of Directors or our Compensation and Personnel Committee.

ALLIANT ENERGY | 2024 Proxy Statement | 15

MEETINGS AND COMMITTEES OF THE BOARD OF DIRECTORS

Nominating and Governance Committee
Members	Carol P. Sanders, Chair Patrick E. Allen Roger K. Newport Thomas F. O’Toole
Independence	All members are independent as required by applicable SEC and Nasdaq rules.
Meetings	The committee held eight meetings in 2023.
Charter	The committee charter is posted at www.alliantenergy.com/investors under the Corporate Governance link.
Responsibilities	The primary responsibilities of the Nominating and Governance Committee are:
	•	Developing criteria and qualifications, including independence standards, for selecting director candidates and identifying qualified candidates for membership on the Board of Directors and Board committees
	•	Making recommendations to the Board of Directors concerning the composition, size, structure and activities of the Board of Directors and Board committees
	•	Assessing and reporting to the Board of Directors on the performance and effectiveness of the Board of Directors and Board committees
	•	Ensuring that directors receive continuing director education
	•	Reviewing and determining whether to approve or ratify any related-person transactions
	•	Reviewing and making recommendations to the Board of Directors with respect to director compensation and benefits
	•	Developing and recommending to the Board of Directors updates to our Corporate Governance Guidelines and other corporate governance policies and practices
	•	Overseeing sustainability, environmental and social responsibility initiatives, including approving the Corporate Responsibility Report
	•	Overseeing the political engagement activity of the Company
	•	Reviewing and making recommendations to the Board regarding shareowner proposals, working with other committees as appropriate
	•	Reviewing and recommending to the Board of Directors succession plans for the Company’s CEO
	Additional information on oversight roles and responsibilities of the Nominating and Governance Committee is provided on page 11.

The Nominating and Governance Committee is responsible for evaluating nominees for director and director candidates. The considerations used by the committee to identify qualified candidates for membership on the Board are described starting on page 2.

In addition, the Nominating and Governance Committee maintains a file of potential director nominees, which is reviewed when we search for a new director. The committee has also engaged a national consulting firm to perform searches for director candidates who meet the current needs of the Board. We pay a fee to consulting firms that assist in our search. In recruiting Mr. Cortina and Ms. Raymond, the Nominating and Governance Committee retained a search firm to help identify director prospects, perform candidate outreach, assist in reference checks and provide other related services.

The Nominating and Governance Committee will consider recommendations for director nominees made by shareowners and evaluate them using the same criteria as for other candidates. Recommendations received from shareowners are reviewed by the Chair of the committee to determine whether each candidate meets the minimum membership criteria set forth in the Corporate Governance Guidelines and, if so, whether the recommended candidate’s expertise and particular set of skills and background fit the current needs of the Board of Directors. Any shareowner recommendation must be sent to the Corporate Secretary of Alliant Energy at 4902 North Biltmore Lane, Madison, Wisconsin 53718 and must include biographical information. Shareowners wishing to nominate director candidates directly for consideration by shareowners must write to our Corporate Secretary in a timely manner as specified in our Bylaws.

Board of Directors Diversity

We strive to create a workplace in which people of diverse backgrounds, talents and perspectives support our purpose. The Nominating and Governance Committee seeks a Board of Directors with diverse opinions, perspectives and backgrounds. We believe we have been effective in assembling a diverse body of individuals as measured by the criteria of age, gender, ethnicity, race, tenure, skills, qualifications and experience specified in our Corporate Governance Guidelines as shown in the charts on page 3. Approximately 64% of our directors are women or ethnically or racially diverse individuals.

ALLIANT ENERGY | 2024 Proxy Statement | 16

MEETINGS AND COMMITTEES OF THE BOARD OF DIRECTORS

Operations Committee
Members	Michael D. Garcia, Chair Ignacio A. Cortina Stephanie L. Cox N. Joy Falotico Thomas F. O’Toole
Independence	All members are independent as defined by the Nasdaq rules.
Meetings	The committee held seven meetings in 2023.
Charter	The committee charter is posted at www.alliantenergy.com/investors under the Corporate Governance link.
Responsibilities	The primary responsibilities of the Operations Committee are:
	•	Reviewing and overseeing environmental policy and planning issues
	•	Reviewing and overseeing safety issues and policies
	•	Reviewing and monitoring issues of strategic importance related to the Company’s operations such as reliability, quality of service, customer care and customer satisfaction
	•	Reviewing and assessing risk in relation to the Company’s operations
	•	Reviewing and monitoring issues with significant impact on the utility capital budgets and energy resource adequacy
	Additional information on oversight roles and responsibilities of the Operations Committee is provided on page 11.

Executive Committee
Members	John O. Larsen, Chair (non-voting) Patrick E. Allen N. Joy Falotico Michael D. Garcia Carol P. Sanders
Independence	All members except Mr. Larsen are independent as defined by the Nasdaq rules.
Meetings	The committee generally does not meet and did not meet in 2023.
Charter	The committee charter is posted at www.alliantenergy.com/investors under the Corporate Governance link.
Responsibilities	The Executive Committee possesses all the power and authority of the Board of Directors when the Board is not in session.

ALLIANT ENERGY | 2024 Proxy Statement | 17

DIRECTOR COMPENSATION

2023 DIRECTOR COMPENSATION

The following table summarizes the compensation paid to or earned by our non-employee directors during 2023.

Name(1)	Fees Earned or Paid in Cash ($)(2)	Change in Pension Value and Non-qualified Deferred Compensation Earnings ($)(3)	All Other Compensation ($)(4)	Total ($)
Patrick E. Allen	$290,000	$0	$0	$290,000
Ignacio A. Cortina	$135,000	$0	$0	$135,000
Stephanie L. Cox	$270,000	$0	$0	$270,000
N. Joy Falotico	$282,500	$0	$0	$282,500
Michael D. Garcia	$277,500	$0	$0	$277,500
Singleton B McAllister	$135,000	$363	$3,500	$138,863
Roger K. Newport	$282,500	$0	$3,500	$286,000
Dean C. Oestreich	$67,500	$6,609	$0	$74,109
Thomas F. O'Toole	$277,500	$1,297	$0	$278,797
Carol P. Sanders	$320,000	$5,877	$0	$325,877
Susan D. Whiting	$206,250	$0	$3,500	$209,750

(1)    Mr. Larsen is also an employee of the Company and received no additional compensation for his service on our Board of Directors and therefore is not included in this table. Ms. Barton is also an employee of the Company but did not serve on the Board in 2023 and is therefore not included in this table. Compensation received by Mr. Larsen and Ms. Barton for 2023 is shown in the Summary Compensation Table. Mr. Oestreich served on the Board until February 2023, Ms. McAllister served on the Board until May 2023 and Ms. Whiting served on the Board until July 2023. Mr. Cortina was appointed to the Board in July 2023. Ms. Raymond did not serve on the Board in 2023 and is therefore not included in this table.

(2)    The amounts shown in this column include the following aggregate dollar amounts deferred and the corresponding number of shares of common stock credited in our Alliant Energy Deferred Compensation Plan Company Stock Account by each of the following directors:

Name	Aggregate Dollar Amounts Deferred	Number of Shares of Common Stock Credited
Stephanie L. Cox	$270,000	5,083
N. Joy Falotico	$240,125	4,518
Michael D. Garcia	$194,250	3,655
Roger K. Newport	$211,875	3,979
Thomas F. O'Toole	$138,750	2,605
Susan D. Whiting	$203,250	3,732

(3)    The amounts shown in this column represent above-market interest on non-qualified deferred compensation.

(4)    The amounts in this column include payments made to charities through the Alliant Energy matching gift program. Infrequently, spouses and guests of directors accompany the directors on a corporate aircraft when the aircraft is already going to a specific destination for a business purpose at no aggregate incremental cost to the Company. No such travel occurred in 2023.

Retainer Fees

In 2023, all non-employee directors, each of whom served on the Boards of Directors of Alliant Energy, IPL and WPL, received an annual cash retainer for service on all Boards, payable quarterly in advance. The following table describes the annual cash retainer received for service in 2023 and the annual retainer that will be received for service in 2024, as well as other fees for director services. Fees for 2023 and 2024 were based on a review of market-based compensation for non-employee directors presented by the Compensation and Personnel Committee’s independent consultant.

Year	Annual Retainer for Service on All Boards	Lead Independent Director	Chair of the Audit Committee	Chair of the Compensation and Personnel Committee	Chair of the Nominating and Governance Committee	Chair of the Operations Committee	Other Audit Committee Members
2023	$270,000	$30,000	$20,000	$20,000	$15,000	$15,000	$5,000
2024	$280,000	$35,000	$25,000	$20,000	$17,500	$17,500	$5,000

ALLIANT ENERGY | 2024 Proxy Statement | 18

DIRECTOR COMPENSATION

Meeting Fees

In 2023, directors did not receive any additional compensation for attendance at Board or committee meetings. The same applies for 2024.

Expense Reimbursements

Pursuant to our directors’ expense reimbursement policy, we reimburse all directors for travel and other necessary business expenses incurred in the performance of their responsibilities for us, including certain continuing education expenses. Committees are provided the opportunity to retain outside independent advisors, as needed. We also extend coverage to directors under our Directors’ and Officers’ Indemnity Insurance Policies.

Receipt of Fees in Stock

For fees paid in 2023 and 2024, directors were encouraged to use 55% of their cash retainer to purchase shares of our common stock through the Shareowner Direct Plan or the Alliant Energy Deferred Compensation Plan. A non-employee director may elect to receive, or the Nominating and Governance Committee may require that a non-employee director be paid, all or any portion of his or her annual cash retainer payment or other cash fees in the form of shares of common stock issued under our 2020 Omnibus Incentive Plan or a successor plan thereto.

Share Ownership Guidelines

Directors are required to be shareowners. The target share ownership level for non-employee directors is the number of shares equal to the value of two times the full annual retainer (equivalent to $540,000 in 2023). Directors have five years after joining the Board of Directors to attain the ownership guideline. Shares held by directors in the Shareowner Direct Plan and the Alliant Energy Deferred Compensation Plan are included in the target goal. As of December 31, 2023, all of our current non-employee directors who have been board members for five years have met the share ownership guidelines. The directors who have joined the board in the last five years are on track to achieve the above ownership goals within the required timeline. We continue to monitor the status of the target ownership levels and review them with the Board of Directors.

Alliant Energy Deferred Compensation Plan

Under the Alliant Energy Deferred Compensation Plan, directors may elect to defer all or part of their retainer fee to an Interest Account, Equity Account, Company Stock Account or Mutual Fund Account. Deferrals credited to the Interest Account receive an annual return based on the 10-year Treasury Bond Rate plus 1.50%. Deferrals credited to the Equity Account are treated as invested in an S&P 500 index fund. Deferrals credited to the Mutual Fund Account are treated as invested in a mutual fund or other investment vehicle offered under our Alliant Energy Corporation 401(k) Savings Plan as selected by the director. Deferrals credited to the Company Stock Account are treated as though invested in our common stock and are credited with dividend equivalents, which are treated as if reinvested in our common stock. Payments from our Alliant Energy Deferred Compensation Plan by reason of death or retirement may be made in a lump sum or in annual installments for up to 10 years at the election of the director. Payments from our Alliant Energy Deferred Compensation Plan for any reason other than death or retirement are made in a lump sum.

Directors’ Charitable Award Program

We maintain a legacy Directors’ Charitable Award Program in which only Ms. McAllister participated in 2023; this program was terminated for all directors who joined the Board after January 1, 2005. The purpose of the program was to recognize our directors’ interest in supporting worthy charitable institutions. Under the program, when a director dies, we will donate a total of $500,000 to up to five qualified charitable organizations selected by the individual director. The individual director derives no financial benefit from the program. We take all deductions for charitable contributions and fund the donations through life insurance policies on the director. Over the life of the program, all costs of donations and premiums on the life insurance policies, including a return of our cost of funds, will be recovered through life insurance proceeds on the director. In 2023, Ms. McAllister received no additional compensation for this program.

Alliant Energy Matching Gift Program

Directors are eligible to participate in the Alliant Energy Foundation, Inc. matching gift program, which is generally available to all employees and retirees. Under this program, the foundation matches 100% of charitable donations over $50 to eligible charities. In 2023, the amount of matching contributions was capped at $3,500 per year for each director.

ALLIANT ENERGY | 2024 Proxy Statement | 19

OWNERSHIP OF VOTING SECURITIES

OWNERSHIP OF VOTING SECURITIES

Listed below are the number of shares of our common stock beneficially owned, except as otherwise indicated, as of March 8, 2024 by: (1) the named executive officers listed in the Summary Compensation Table; (2) all of our director nominees and directors; and (3) all director nominees, directors and executive officers as a group. No individual director or executive officer owned more than 1% of the outstanding shares of common stock on that date. The directors and executive officers as a group owned less than 1% of the outstanding shares of common stock on that date. No director or executive officer owns any other equity of Alliant Energy Corporation or any of its subsidiaries. None of the shares held by the executive officers and directors are pledged.

Name of Beneficial Owner	Shares Beneficially Owned(1)	Restricted Stock Units(2)	Total
NAMED EXECUTIVE OFFICERS
John O. Larsen	247,581	62,825	310,406
Lisa M. Barton	1,100	35,344	36,444
Robert J. Durian	107,889	20,296	128,185
Raja Sundararajan	500	10,056	10,556
Terry L. Kouba	48,034	6,463	54,497
David A. de Leon	31,933	6,463	38,396
DIRECTOR NOMINEES
Ignacio A. Cortina	1,503		1,503
Stephanie L. Cox	7,139		7,139
Roger K. Newport	22,591		22,591
Christie Raymond
Carol P. Sanders	66,761		66,761
DIRECTORS
Patrick E. Allen	43,783		43,783
N. Joy Falotico	11,172		11,172
Michael D. Garcia	15,203		15,203
Thomas F. O’Toole	35,828		35,828
All Executive Officers and Directors as a Group (16 people)	656,375	144,553	800,928

(1)     Ms. Barton’s share ownership is shown in the named executive officer section. She is also a director nominee. Mr. Larsen’s share ownership is shown in the named executive officer section. He is also a director. Total shares of Alliant Energy common stock outstanding as of March 8, 2024 were 256,376,510. Named executive officers and directors own fractional shares of common stock. Fractional shares have been rounded to the nearest whole share in this table and in this footnote. Included in the beneficially owned shares shown are the following number of shares of common stock held in deferred compensation plans: Mr. Allen — 39,555; Mr. Cortina — 1,403; Ms. Cox — 6,639; Ms. Falotico — 9,962; Mr. Garcia — 15,203; Mr. Kouba — 868; Mr. Larsen — 20,158; Mr. Newport — 21,591; Mr. O’Toole — 35,628; Ms. Sanders — 66,761; (all executive officers and directors as a group — 217,767).

(2)    Unvested Restricted Stock Units do not have investment or voting power and are not considered “beneficially owned” under SEC rules.

The following table sets forth information regarding beneficial ownership by the only owners known to us to own more than 5% of Alliant Energy’s common stock. The beneficial ownership set forth below has been reported on Schedule 13G filings with the SEC by the beneficial owners, as of the respective date provided below.

ALLIANT ENERGY | 2024 Proxy Statement | 20

OWNERSHIP OF VOTING SECURITIES

Amount and Nature of Beneficial Ownership
	Voting Power		Investment Power
Name and Address of Beneficial Owner	Sole	Shared	Sole	Shared	Aggregate	Percent of Class
The Vanguard Group 100 Vanguard Blvd. Malvern, PA 19355 (dated as of February 13, 2024)	0	434,877	30,889,968	1,204,244	32,094,212	12.58%
BlackRock Inc. 50 Hudson Yards New York, NY 10001 (dated as of January 24, 2024)	21,913,481	0	23,143,382	0	23,143,382	9.10%
State Street Corporation 1 Congress Street, Suite 1 Boston, MA 02114-2016 (dated as of January 30, 2024)	0	8,541,602	0	13,358,335	13,410,618	5.31%

Alliant Energy owns all of the outstanding common stock of IPL and WPL.

ALLIANT ENERGY | 2024 Proxy Statement | 21

COMPENSATION DISCUSSION AND ANALYSIS

ALLIANT ENERGY | 2024 Proxy Statement | 22

COMPENSATION DISCUSSION AND ANALYSIS

COMPENSATION DISCUSSION AND ANALYSIS

INTRODUCTION

Our purpose at Alliant Energy is to serve customers and build strong communities. Our purpose is supported by our strategy and values, and our strategy is focused on meeting the evolving expectations of customers while providing an attractive return for investors. Our purpose-driven strategy is focused on our customers and includes providing affordable energy solutions, making customer-focused investments and growing customer demand.

Our executive compensation program is guided by our purpose and values and is designed to promote our strategy. It does so by providing market-based pay and rewarding achievement related to our customer-focused strategy. The principles and components of our compensation program are regularly reviewed by our Compensation and Personnel Committee, our Chief Executive Officer and the Compensation and Personnel Committee’s independent compensation consultant to ensure that they meet the objectives of the program.

Our named executive officers for 2023 were (with positions held as of 2023 fiscal year end):
1.	John O. Larsen: Chief Executive Officer of Alliant Energy; Board Chair of Alliant Energy, IPL and WPL
2.	Lisa M. Barton: President and Chief Operating Officer of Alliant Energy; Chief Executive Officer of IPL and WPL
3.	Robert J. Durian: Executive Vice President and Chief Financial Officer
4.	Raja Sundararajan: Executive Vice President
5.	David A. de Leon: Senior Vice President; President of WPL
6.	Terry L. Kouba: Senior Vice President; President of IPL

Mr. Larsen served as Board Chair, President and Chief Executive Officer (CEO) of Alliant Energy and Board Chair and CEO of IPL and WPL until February 27, 2023. On February 27, 2023, Mr. Larsen became Board Chair and CEO of Alliant Energy and Board Chair of IPL and WPL. Effective January 1, 2024, Mr. Larsen was succeeded as CEO of Alliant Energy by Ms. Barton and Mr. Larsen became Executive Chairman and Chairman of the Board of Alliant Energy.

Ms. Barton joined the Company as President and Chief Operating Officer (COO) of Alliant Energy and CEO of IPL and WPL on February 27, 2023. She was named President and CEO of Alliant Energy effective January 1, 2024.

Mr. Sundararajan joined the Company on June 12, 2023.

Six named executive officers are included for IPL and WPL as Mr. Larsen and Ms. Barton both served as CEO of IPL and WPL during 2023. Unless otherwise noted, this Compensation Discussion and Analysis considers Mr. Larsen’s position as CEO because he was CEO of Alliant Energy for all of fiscal 2023 and considers Ms. Barton’s position as President and COO of Alliant Energy.

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COMPENSATION DISCUSSION AND ANALYSIS

HOW WE PERFORMED

2023 Highlights

The charts below show some of our key performance highlights from 2023.

                                                

* 2021 GAAP EPS from consolidated earnings from continuing operations was $2.63. Adjusted EPS from Continuing Operations in 2021 excluded a loss of $0.02 per share for the non-cash charge related to the redemption of IPL preferred stock. 2022 GAAP EPS from consolidated earnings from continuing operations was $2.73. Adjusted EPS from Continuing Operations for 2022 excludes $0.03 per share of charges related to the Iowa state income tax rate change, $0.02 per share of charges related to retirement plan settlement losses, and $0.02 per share of charges related to an ATC base return on equity reserve adjustment. 2023 GAAP EPS from consolidated earnings from continuing operations was $2.78. Adjusted EPS from Continuing Operations in 2023 excluded $0.04 per share of charges related to remeasurement of deferred tax assets due to Iowa state income tax rate changes for non-utility and parent companies.

HOW WE DETERMINE EXECUTIVE COMPENSATION

Our compensation vision is to provide compensation programs that promote the achievement of our customer-focused strategy, align executives’ and employees’ interests with the success of the Company, and provide competitive compensation opportunities to attract, retain and motivate a highly talented executive team and workforce. Our philosophy is to design compensation programs that drive high performance and reward that performance competitively within our industry. We believe that everyone should clearly understand their compensation and how it connects to individual and shareowner value.

The objectives for our executive compensation program are as follows:

•    Reward Strong Performance: motivate and reward executives to contribute to the achievement of our business objectives by aligning pay and performance through variable at-risk compensation

•    Align Executives’ and Shareowners’ Interests: align executive officers’ interests with those of our shareowners by delivering a significant proportion of total compensation through equity, tying a significant portion of our long-term incentive pay directly to relative total shareowner return and net income growth, tying annual incentive compensation to meeting earnings per share targets and to targets that measure the customer experience, emissions reductions, diversity and safety, and requiring executives to own Alliant Energy stock

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COMPENSATION DISCUSSION AND ANALYSIS

•    Maintain Consistency: drive sustainable performance and improvement by maintaining an appropriate level of executive compensation design consistency

•    Provide Competitive Compensation Opportunities: attract and retain the best possible personnel through competitive compensation that is comparable to that of similar companies but driving what is right for our strategy and stakeholders

These compensation practices help us achieve our program objectives:

•    Incentive-Based At-Risk Compensation: a substantial portion of our executive officers’ compensation is based on achievement of financial and operational performance goals, with long-term equity-based awards delivering a majority of the incentive-based pay

•    Equity Ownership: long-term incentive awards settle in stock, which, combined with our share ownership requirement, promotes executive officer ownership of our common stock

•    Minimize Systemic Risk-Taking: compensation programs are developed to properly mitigate unintended risk-taking, providing a mix of long-term and short-term compensation and using multiple performance criteria to determine awards

•    Market Compensation: total aggregate compensation levels are reviewed against market compensation levels to ensure that we provide a pay opportunity competitive with the market median

•    Access to Retirement Programs: executive officers have access to retirement plans commonly in use among comparable companies, including deferred compensation plans, certain non-qualified retirement plans and 401(k) savings plans

The Compensation and Personnel Committee considers these objectives and practices in its regular reviews of the executive compensation program.

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COMPENSATION DISCUSSION AND ANALYSIS

HOW WE PAY NAMED EXECUTIVE OFFICERS

Our components of executive compensation are:

Component	Description	Objective within Compensation Program
Base Salary	Fixed compensation, subject to annual review and adjusted in response to changes in responsibility, performance, strategic importance, experience in role and competitive practice	•	Provides base compensation at a level consistent with competitive practices
		•	Reflects roles, responsibilities, skills, experience and performance
		•	Adheres to competitive market practices
Short-Term (Annual) Incentive Compensation	Annual cash incentive pay based on achievement of objective Company performance measures	•	Motivates and rewards achievement of annual financial and operational goals
		•	Aligns management interests with investor and customer interests by linking pay and performance
		•	Promotes achievement of strategic plan by linking pay to achievement of strategic goals
Long-Term (Equity) Incentive Compensation	Incentive-based equity awards payable if performance goals are achieved during a sustained period	•	Motivates and rewards financial performance - relative total shareowner return and net income growth - over a sustained period
		•	Motivates and rewards achievement of a diverse workforce over a sustained period
		•	Aligns management and shareowner interests by promoting management ownership
		•	Enhances retention of management personnel
		•	Links pay to performance relative to peers
Long-Term (Equity) Service-Based Compensation	Time-vesting equity awards earned after three years, subject to continuous employment	•	Enhances retention of management personnel
		•	Aligns management and shareowner interests by promoting management ownership
Retirement and Other Benefits	Tax-qualified, deferred compensation and other benefits	•	Provides for current and future needs of the executives and their families
		•	Enhances recruitment and retention
		•	Adheres to competitive market practices
Post-Termination Compensation	Key Executive Employment and Severance Agreements (KEESAs) and Executive Severance Plan provide contingent amounts payable only if employment is terminated under certain conditions	•	Enhances retention of management personnel by providing employment continuity
		•	Encourages the objective evaluation and execution of potential changes to the Company’s strategy and structure

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COMPENSATION DISCUSSION AND ANALYSIS

Our compensation components are weighted toward incentive-based compensation, as shown below:

        

Base Salary

The Compensation and Personnel Committee annually reviews and adjusts salaries based on changes in the market, responsibilities and performance against job expectations, strategic importance and experience in the role. The Company is not contractually bound by employment or other agreements to pay particular levels of base salary to our executive officers, thereby affording flexibility in those determinations.

The following table sets forth the base salaries of each named executive officer as of the end of the 2023 and 2022 calendar years, as well as the percentage change from the prior year.

Named Executive Officer	2023  Base Salary	2022  Base Salary	Percentage Increase
John O. Larsen	$1,133,600	$1,090,000	4.0%
Lisa M. Barton	$825,000	—	—
Robert J. Durian	$650,000	$610,000	6.6%
Raja Sundararajan	$600,000	—	—
David A. de Leon	$440,000	$430,000	2.3%
Terry L. Kouba	$440,000	$430,000	2.3%

The salary increases reflect efforts to keep total targeted compensation in line with market and to retain talent. Ms. Barton and Mr. Sundararajan joined the Company in 2023.

Short-Term (Annual) Incentive Pay

Executive officers participate in the Executive Short-Term Incentive Pay (EXSTIP) Plan that provides the opportunity for annual cash payments tied directly to the achievement of key financial goals and operational goals related to the customer experience, emissions reductions, diversity and safety. The Compensation and Personnel Committee sets Company and individual goals guided by our purpose, our values and our strategic plan. The Company goals balance financial and operational objectives to drive value for both our shareowners and customers.

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COMPENSATION DISCUSSION AND ANALYSIS

The Company goals for 2023, their weightings, and our performance compared to those goals are shown below.

Goal	Target Percentage of Performance Pool	Target	Actual	Percentage Payment Toward Performance Pool
Consolidated EPS from Continuing Operations (EPS)	70%	EPS:(1) Threshold: $2.73 Target: $2.91 Maximum: $3.03	$2.82	52.5%
Customer Experience	5%	Customer Interaction Survey: Threshold: 8.07 Target: 8.47 Maximum: 8.67	8.61	8.5%
	5%	SAIDI: Threshold: 90% Target: 100% Maximum: 115%	127%	10%
	5%	SAIFl: Threshold: 90% Target: 100% Maximum: 115%	120%	10.0%
Environmental	5%	Annual Progress Towards Long-Term Emission Reduction Goal: Threshold: 38% Target: 44% Maximum: 49%	38%	2.5%
Diversity, Equity and Inclusion	5%	Creating a Culture of Inclusivity and Belonging: Threshold: 10 Target: 20 Maximum: 30	10	2.5%
Safety	2.5%	Total Recordable Incident Rate Reduction: Threshold: 5% Target: 15% Maximum: 25%	(17)%	—%
	2.5%	Lost Time Incident Rate Reduction: Threshold: 5% Target: 15% Maximum: 25%	27%	5.0%
TOTAL	100.0%			91%

(1)2023 GAAP EPS from consolidated earnings from continuing operations was $2.78. Adjusted EPS in 2023 excluded $0.04 per share of charges related to remeasurement of deferred tax assets due to Iowa state income tax rate changes for non-utility and parent companies.

The Compensation and Personnel Committee approved earnings per share as the financial goal to reward earnings growth. This aligns with our strategy and rewards meeting the expectations of our shareowners. Operational goals related to customer experience, environment, diversity and safety reflect our corporate purpose and values.

The customer experience goals are linked to our customer-focused strategy and guided by our purpose to offer superior service to our customers. The customer interaction target measures our efforts to create a simple, personalized experience for our customers by soliciting feedback after customer interactions and averaging the feedback responses. The System Average Interruption Duration Index (SAIDI) measures outage duration and the System Average Interruption Frequency Index (SAIFI) measures outage frequency. Both of these goals measure our current year reliability compared to our 10-year historical average.

Other operational goals are linked to our strategy and include emissions reductions, diversity, equity and inclusion, and safety.

The emissions reduction goal emphasizes our commitment to clean energy and rewards annual progress toward the Company’s long-term aspiration of a 50% reduction in CO2 emissions by 2030 from 2005 levels.

Our diversity goals support and reward an inclusive culture. They measure our achievement on three metrics that we believe are important in creating a culture of inclusivity and belonging. Each component is worth ten points and is measured on a pass/fail scale. The components include: developing and advancing diverse talent in succession pools for director and above positions, prevalence of female and people of color promotions, and diverse candidate slates for salaried roles filled externally.

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COMPENSATION DISCUSSION AND ANALYSIS

Our safety goals measure our most important value - safety. They reward reductions in injuries compared to our three-year average and reductions in lost-time incidents compared to last year.

Each performance goal is measured independently of other goals. Company performance compared to the goals was 91% as shown in the chart above. The maximum amount payable for Company performance is capped at 200% of target.

Individual performance goals are set to drive an individual’s contribution to our strategic business imperatives. The goals can be both qualitative and quantitative and can vary for each executive officer. The Compensation and Personnel Committee may use individual performance to modify the amount of an incentive award earned by an executive officer. For 2023, the committee did not modify the awards of any named executive officer based on individual performance, and all payouts to the named executive officers for 2023 were calculated based on achievement of the Company goals shown above.

Each target payout percentage under the EXSTIP Plan is set by the Compensation and Personnel Committee based on survey data, experience in a position, strategic importance and individual responsibilities. Target payouts as a percentage of base salary for 2023 are set forth below. They reflect a slight increase from 2022 due to efforts to keep total targeted compensation in line with market. Ms. Barton and Mr. Sundararajan joined the Company in 2023.

Named Executive Officer	EXSTIP Plan Target Payout  as a Percentage of 2023 Base Salary
John O. Larsen	140%
Lisa M. Barton	85%
Robert J. Durian	80%
Raja Sundararajan	75%
David A. de Leon	65%
Terry L. Kouba	65%

Amounts earned in 2023 under the EXSTIP Plan are provided in the Non-Equity Incentive Plan Compensation column of the Summary Compensation Table.

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COMPENSATION DISCUSSION AND ANALYSIS

Long-Term Equity Awards

We award long-term equity compensation to focus our executive officers on building shareowner value, to retain management personnel, to encourage sustained performance on key metrics, and to align management interests with shareowner interests and customer interests over a multi-year period. In 2023, we granted long-term awards under our 2020 Omnibus Incentive Plan to our named executive officers as shown below.

Award Type	Portion of Long-Term Target Award	Performance Metric	Payout Range as a Percentage of Target	Settlement
Performance Shares	35%	Relative Total Shareowner Return	0-200%	Shares
Performance Restricted Stock Units - Net Income	35%	Cumulative Net Income Growth	0-200%	Shares
Performance Restricted Stock Units - DEI	5%	Diversity Metrics	0-200%	Shares
Restricted Stock Units	25%	Time-vesting	100%	Shares

As shown above, 75% of the target long-term equity awards granted to our named executive officers are performance-based, payable only if minimum threshold goals are met. All outstanding long-term equity awards are settled in shares of our common stock which increases equity ownership by our executives to better align executives’ and shareowners’ interests.

Performance shares reward total shareowner return relative to our performance peer utility companies in the Edison Electric Institute (EEI) Stock Index over a three-year performance period. Performance restricted stock units separately reward absolute net income growth and achievement of diversity in our workforce. Performance shares and performance restricted stock units are forfeited if threshold results are not achieved during the applicable performance period.

Service-based restricted stock units, which represent a minority of our total long-term incentive, vest in a single installment based on continued service over three years. These awards enhance retention of management personnel and align our executive officers’ long-term financial interests to the experience of our shareowners.

These long-term equity awards are forfeited if the executive officer voluntarily leaves the Company (other than for retirement) or is terminated for cause during the time-vesting period.

Currently, we do not issue stock options, do not have any outstanding stock options and do not anticipate issuing stock options.

2023 target long-term incentive grant values as a percentage of base salary are set forth below.

Named Executive Officer	2023 Target Long-Term Equity Grant Value as a Percentage of Base Salary
John O. Larsen	450%
Lisa M. Barton	300%
Robert J. Durian	230%
Raja Sundararajan	170%
David A. de Leon	105%
Terry L. Kouba	105%

The target long-term incentive grant values reflect increases from 2022 for our executive officers due to efforts to keep total targeted compensation in line with market. Ms. Barton and Mr. Sundararajan joined the Company in 2023. The Compensation and Personnel Committee considers survey data, experience in a position, strategic importance, individual responsibilities and the competitiveness of the total compensation package when setting long-term incentive opportunities. The target dollar value of the long-term equity awards is determined prior to the grant date, and we grant the number of target units necessary to approximate that dollar value based on the fair market value of our share price on the grant date. The target units are allocated among the four different types of awards as set forth in the table above.

Performance Shares

Performance shares are intended to reward Company performance relative to our peers in the EEI Stock Index. Vesting of the performance shares granted in 2023 is based on our relative total shareowner return over the three-year performance period that runs from January 1, 2023 through December 31, 2025 as follows:

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COMPENSATION DISCUSSION AND ANALYSIS

Three-Year Total Shareowner Return Relative To EEI Stock Index	Percentage of Target  Value Payout
90th percentile or greater	200%
80th percentile	175%
70th percentile	150%
60th percentile	125%
50th percentile	100%
45th percentile	75%
40th percentile	50%
Below 40th percentile	0%

The total shareowner return calculation represents the cumulative return for the three-year performance period reflecting price appreciation and reinvested dividend payments. Performance shares pay at target if our relative total shareowner return over three years is equal to the median performance of a specific peer group selected by the Compensation and Personnel Committee. Consistent with prior years, the committee selected the EEI Stock Index as the peer group for the 2023 grants of performance shares. We believe the comparison to the EEI Stock Index appropriately assesses our performance relative to other publicly traded utilities. Performance share payouts are capped at 200% of the target payout.

Any dividend equivalents credited on performance shares are treated as reinvested, but are not payable to the participant unless the performance target is met and vesting is completed.

Performance shares have double-trigger acceleration upon a change in control. Upon a change in control, the outstanding awards vest at target and are valued based on the share prices on the date immediately preceding the change in control date. The awards are paid at the end of the three-year performance period provided the executive is still employed by the Company or had a qualifying termination event.

The total shareowner return for the 2021 performance share grant (performance period ended on December 31, 2023) ranked at the 44th percentile relative to the peer group. As a result, our named executive officers earned 70% of the target award for the 2021-2023 performance period. Additional information about the performance share payouts for the 2021-2023 performance period is provided in the 2023 Option Exercises and Stock Vested table.

The EEI Stock Index, which we use only to measure relative performance for our performance shares, was composed of the following companies as of December 31, 2023:

ALLETE, Inc.	Entergy Corporation	Otter Tail Corporation
Ameren Corporation	Evergy, Inc.	PG&E Corporation
American Electric Power Company, Inc.	Eversource Energy	Pinnacle West Capital Corporation
Avangrid, Inc.	Exelon Corporation	PNM Resources, Inc.
Avista Corporation	FirstEnergy Corp.	Portland General Electric Company
Black Hills Corporation	Hawaiian Electric Industries, Inc.	PPL Corporation
CenterPoint Energy, Inc.	IDACORP, Inc.	Public Service Enterprise Group
CMS Energy Corporation	MDU Resources Group Inc.	Sempra Energy
Consolidated Edison, Inc.	MGE Energy, Inc.	Southern Company
Dominion Energy Inc.	NextEra Energy, Inc.	Unitil Corporation
DTE Energy Company	NiSource Inc.	WEC Energy Group, Inc.
Duke Energy Corporation	NorthWestern Corporation	Xcel Energy, Inc.
Edison International	OGE Energy Corp.

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COMPENSATION DISCUSSION AND ANALYSIS

Restricted Stock Units - Performance and Service-Based

In 2023, the Compensation and Personnel Committee granted three types of restricted stock units that each vest over a three-year period that runs from January 1, 2023 through December 31, 2025. These grants are allocated between performance-based restricted stock units that vest based on pre-established net income and diversity metrics and service-based restricted stock units that vest based on continued employment.

Any dividend equivalents credited on restricted stock units, whether performance-based or service-based, are treated as reinvested, but are not payable to the participant unless the performance target or service requirement, as applicable, is met and vesting is completed.

Restricted stock units have double-trigger acceleration upon a change in control. Upon a change in control, the outstanding awards vest at target and are valued based on the Company’s stock price as of the trading day immediately preceding the change in control date. The awards are paid at the end of the three-year vesting period provided the executive is still employed by the Company or had a qualifying termination event.

    Performance Restricted Stock Units - Net Income

Performance restricted stock units based on a net income metric are intended to reward absolute long-term growth in our profitability. Vesting of the performance restricted stock units granted in 2023 is based on achieving a cumulative net income growth target over the three-year performance period as follows:

Three-Year Cumulative Consolidated Net Income from Continuing Operations Growth	Percentage of Target  Value Payout
7.5%	200%
6.5%	150%
5.5%	100%
4%	50%
Below 4%	0%

Vesting at target requires 5.5% compounded annual growth, which is based on the successful and timely execution of our strategic plan. The target is calculated based on achieving a cumulative consolidated net income target over the performance period, excluding certain items as permitted by the equity plan under which the performance restricted stock units were granted, such as charges for reorganizing and restructuring, discontinued operations, asset write-downs, gains or losses on the disposition of an asset or business, mergers, acquisitions or dispositions and unusual or non-recurring items of gain or loss, in each case, as identified in the Company’s audited financial statements or periodic reports. Performance restricted stock units granted in 2023 will vest at target if our cumulative consolidated net income from continuing operations over the performance period totals $2,328.5 million.

Performance restricted stock units granted in 2021 (performance period ended on December 31, 2023) had a net income target calculated based on achieving a cumulative consolidated net income from continuing operations over the performance period equated to a compounded annual growth rate of 5.5%, excluding certain items described above as permitted by the 2020 Omnibus Incentive Plan. Cumulative consolidated net income for the performance period ended December 31, 2023 was $2.0728 billion, which represented 7.4% three-year compounded annual growth of consolidated net income from continuing operations. As a result, our named executive officers earned 196% of the target award for the 2021-2023 performance period. Additional information about the payout of the performance restricted stock units for the 2021-2023 performance period is provided in the 2023 Option Exercises and Stock Vested table.

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COMPENSATION DISCUSSION AND ANALYSIS

Performance Restricted Stock Units - Diversity

Performance restricted stock units based on DEI metrics are intended to reward successful implementation of our diversity efforts over time. Diversity performance restricted stock units were granted for the first time in 2022. Vesting of the performance restricted stock units granted in 2023 is based on achieving a specified level of representation of women and people of color in our workforce at the end of the three-year performance period as follows:

Women		People of Color
Percent of Workforce	Percentage of Target Value Payout	Percent of Workforce	Percentage of Target Value Payout
25.20%	50%	7.50%	50%
25.50%	100%	8.00%	100%
25.75%	150%	8.25%	150%
26.00%	200%	8.50%	200%

Vesting at target requires growth in underrepresented populations in our workforce. These targets reward sustained progress toward the Company’s aspiration to have a workforce that reflects the demographics of the labor force in the communities we serve. Performance restricted stock units granted in 2023 will vest at target if women represent 25.5% of our workforce and people of color represent 8.0% of our workforce at the end of the performance period. Each target is equally weighted and measured independently. Performance restricted stock unit payouts are capped at 200% of the target payout.

    Service-based Restricted Stock Units

Service-based restricted stock units are time-vesting awards for which forfeiture restrictions lapse in a single installment after three years, subject to continuous employment.

Additional information about the restricted stock unit payouts for the 2021-2023 vesting period is provided in the 2023 Option Exercises and Stock Vested table.

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COMPENSATION DISCUSSION AND ANALYSIS

Retirement and Other Benefits

We offer retirement and other benefit programs to our named executive officers that are consistent with those of our peers. We provide these benefits to remain competitive with the general market for executive officers. The benefit programs are designed to be competitive in attracting, retaining and motivating our named executive officers by providing competitive retirement benefits and incentivizing the promotion of the Company’s, customers’, and shareowners’ interests over a long time horizon. A brief description of the plans is set forth in the table below.

Benefit	Description
Alliant Energy  Deferred Compensation Plan (AEDCP)(1)	Enables participants to defer up to 100% of base salary and annual incentive pay on a pre-tax basis and to receive earnings or incur losses on the deferrals until the date of distribution. The shares of Alliant Energy common stock identified as obligations under the AEDCP are held in a rabbi trust.
Alliant Energy Cash Balance Pension Plan(2)	Offers flexible payment options and steady growth of retirement funds. The Cash Balance Pension Plan was frozen for participants effective August 2, 2008. Employees hired after December 25, 2005 are not eligible to participate.
Alliant Energy Corporation 401(k) Savings Plan	Provides for a match of $0.50 on each dollar for the first 8% of compensation contributed to the 401(k) Savings Plan account by the participants up to the IRS maximum. In addition, we contribute a percentage of participants’ salaries to their 401(k) accounts. The amount of the Company contribution ranges from 4% to 6% of a participant’s salary, depending on the participant’s age and number of years of service at the Company.
Alliant Energy Excess Retirement Plan(2)	Provides the benefit that the participants would have earned under the Cash Balance Pension Plan and the 401(k) Savings Plan but for statutory limitations on employer-provided benefits imposed on those tax-qualified plans and accruals earned on their deferrals into the AEDCP.
Alliant Energy Supplemental Retirement Plan (SRP)(2)	Generally provides retirement compensation in addition to the benefits provided by the Cash Balance Pension Plan and the 401(k) Savings Plan, which are limited by the Internal Revenue Code of 1986 (tax code), and the Alliant Energy Excess Retirement Plan. Generally payable only if the executive remains with us until retirement, disability or death. We do not anticipate providing SRP benefits to executives hired or promoted in 2013 or thereafter.

(1)    See 2023 Non-qualified Deferred Compensation below for more information regarding the AEDCP.

(2)    See 2023 Pension Benefits below for more information regarding the Alliant Energy Cash Balance Pension Plan, the Excess Retirement Plan and the SRP.

The Compensation and Personnel Committee reviews benefit programs on a periodic basis to determine effectiveness and identify any necessary changes. Based on market data showing a trend away from SRPs, we do not anticipate providing SRP benefits to executives hired or promoted in 2013 or thereafter. The committee does not believe this change will inhibit our ability to attract and retain executive officers.

We provide limited perquisites to our named executive officers. Our named executive officers are eligible for executive physicals, reimbursement of financial planning expenses and long-term disability insurance which are in excess of the benefits provided to our other non-executive employees. The Compensation and Personnel Committee recognizes that the CEO’s job duties require significant travel. For that reason, the Compensation and Personnel Committee permitted the CEO to use the corporate aircraft and established guidelines for personal use of the corporate aircraft in 2023. Under those guidelines, the CEO was able to use corporate aircraft for personal travel for himself and his family subject to certain limitations and conditions including limits on the use of the aircraft for personal travel, oversight by the committee and proper imputation of income to the CEO.

In connection with Mr. Sundararajan’s commencement of employment in 2023, the Company agreed to reimburse him for expenses related to relocating to Madison, Wisconsin, and tax restoration payments for the relocation reimbursements. The reimbursements are subject to repayment terms in the event Mr. Sundararajan terminates his employment within 24 months of receipt of the reimbursements.

Leadership Transition

In 2023, Ms. Barton was provided with a cash signing bonus of $1.7 million when she was appointed President and COO of Alliant Energy and CEO of IPL and WPL. This bonus was provided in consideration of relocation costs, any foregone compensation from her previous

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COMPENSATION DISCUSSION AND ANALYSIS

employer, and was important to our successful recruitment of Ms. Barton in a competitive market for top talent in our industry. The signing bonus is subject to repayment terms in the event that Ms. Barton terminates her employment within three years of joining the Company.

Effective January 1, 2024, Ms. Barton was elected President and CEO of Alliant Energy and Mr. Larsen was elected Executive Chairman of the Company. The Compensation and Personnel Committee followed the process for setting compensation outlined below to set the 2024 compensation of Ms. Barton and Mr. Larsen.

In connection with Ms. Barton’s becoming President and CEO of Alliant Energy, effective as of January 1, 2024, the Compensation and Personnel Committee set her base salary at $1,075,000, her target percentage under the 2024 EXSTIP Plan at 125% of base salary, and her long-term incentive target percentage for awards made in 2024 at 420% of base salary.

In connection with Mr. Larsen’s becoming Executive Chairman and remaining an employee of the Company, effective as of January 1, 2024, the Compensation and Personnel Committee set his base salary at $967,500, his target percentage under the 2024 EXSTIP Plan at 120% of base salary, and his long-term incentive target percentage for awards made in 2024 at 400% of base salary.

Post-Termination Compensation

    Key Executive Employment and Severance Agreements

We currently have in effect Key Executive Employment and Severance Agreements (KEESAs) with our executive officers, including our named executive officers, and certain other key employees, which provide for double-trigger severance benefits under certain circumstances following a change in control.

Benefits under the KEESAs are paid only if: (1) a change in control occurs and (2) a qualifying termination of employment occurs within 180 days prior to the change in control or two years after the change in control. A qualifying termination occurs if the executive officer’s employment terminates as a result of (a) termination by the Company, other than by reason of death or disability or for cause, or (b) termination by the executive officer for good reason. This double-trigger mechanism ensures that only those executive officers adversely affected by a change in control will receive benefits under the KEESAs.

The KEESAs provide a cash termination payment of 2.99 times for the CEO and Executive Chairman, and for the other executive officers, two times the sum of the executive officer’s (i) annual base salary and (ii) target annual incentive pay for the year in which the termination occurs. The KEESAs also provide that, consistent with the terms of outstanding equity award agreements, any change in control payments under outstanding equity awards will be paid pursuant to the terms of the equity plan and the agreements under which the awards were granted. We do not offer severance arrangements with executive officers that provide a multiplier equal to or greater than three.

The KEESAs are generally designed to avoid the adverse effects of Section 280G of the tax code. Each KEESA provides that if any portion of the benefits under the KEESA or under any other agreement would constitute an excess parachute payment for purposes of the tax code, the executive officer may receive the greater, on an after-tax basis, of either a payment $1 less than the maximum amount he or she may receive without becoming subject to the 20% excise tax or the full payment subject to applicable excise taxes, for which the executive officer would be personally responsible. None of the KEESAs have Section 280G tax gross-up provisions.

We believe that the level of the benefits provided by the amended KEESAs to the executive officers reflects the appropriate amount of compensation necessary for our executive officers to consider our shareowners’ interests without potential influence of their personal interests. We believe the security afforded by the KEESAs will help the executives to remain focused on business continuity and will reduce the distraction of the executives’ reasonable concerns regarding future employment during the uncertainty of a proposed change in control transaction.

Additional information about the KEESAs is provided in the 2023 Potential Payments Upon Termination or Change in Control section.

    Executive Severance Plan

We also maintain the executive officer severance benefit plan, which compensates an executive officer in the event that his or her position is eliminated or significantly altered. As with our KEESA benefit, our executive officer severance benefit plan is designed to enable executives to remain focused on our business without undue personal concerns over job security. The plan provides for:

•Severance pay equal to one year’s annual base salary

•Up to 18 months of COBRA coverage or participation in our subsidized retiree medical insurance program if eligible (six months of which are paid by us)

•Outplacement services and/or tuition reimbursement of up to $10,000

•Access to our employee assistance program

Eligibility for benefits under this plan is conditioned upon an executive executing a severance agreement and release form. All severance packages of executive officers are approved by the Compensation and Personnel Committee. We believe our executive severance plan is consistent with industry-wide standards.

    Employment Agreements and Separation Arrangements

We do not have any other employment agreements or separation arrangements with our executive officers.

ALLIANT ENERGY | 2024 Proxy Statement | 35

COMPENSATION DISCUSSION AND ANALYSIS

HOW WE ADDRESS GOVERNANCE AND RISK

Process For Setting Executive Compensation

Entity	Role
Compensation and Personnel Committee	The Compensation and Personnel Committee reviews and sets each component and level of compensation for the Company’s named executive officers and other executive officers. The Compensation and Personnel Committee’s responsibilities include: • Review and approve executive officers’ compensation packages • Review and approve corporate incentive goals and objectives relevant to compensation • Evaluate individual performance results in light of these goals and objectives The Compensation and Personnel Committee is made up of independent directors and meets regularly in executive sessions without management present. The committee is supported in its work by the human resources staff and by the committee’s outside consultant.
Chief Executive Officer	The CEO recommends to the Compensation and Personnel Committee the level of compensation for the Company’s named executive officers and other executive officers that report to the CEO. The CEO considers the following factors when making recommendations: • Executive performance • Experience in the role • Strategic importance • Internal pay equity • Market data, as discussed below • Information provided by the Company’s human resources staff The CEO is present and available to the Compensation and Personnel Committee during their meetings with respect to the compensation of the Company’s other named executive officers and other executive officers that report to the CEO. However, the committee discusses and determines the CEO’s compensation and the Executive Chairman’s compensation in executive session.
Independent Compensation Consultant	The Compensation and Personnel Committee engaged Pay Governance LLC as its independent external advisor. The committee receives data, analyses and support from Pay Governance. During 2023, Pay Governance participated in committee meetings, analyzed the competitive level of compensation for each of the named executive officers and provided information regarding executive compensation trends and market practices. Pay Governance reports solely to the committee and meets with the committee at each meeting in executive session.
Market Data	Each year, Pay Governance prepares a market compensation analysis based on companies of similar size in terms of revenue and market capitalization, including those in the energy services industry and in general industry. This analysis assists the Compensation and Personnel Committee in establishing executive officer compensation levels to allow us to remain competitive in our market. The market data used in 2023 included two surveys: • General Industry Data: Willis Towers Watson’s 2022 General Industry Executive Compensation Database, which includes pay data for approximately 1,000 general industry companies • Peer Utility Data: Willis Towers Watson’s 2022 Energy Services Industry Executive Compensation Database General industry survey information was size-adjusted using regression analysis to correspond to each officer’s scope of responsibility. The Compensation and Personnel Committee used equally blended general industry data and energy industry data to determine the market reference point used for corporate positions, which in 2023 were held by Mr. Larsen, Ms. Barton, Mr. Durian, and Mr. Sundararajan. Energy industry data was used as a secondary market reference point for these positions. A utility peer group was used as the sole market reference point for utility-specific positions, such as that held by Mr. Kouba and Mr. de Leon. This peer group included: Atmos Energy Corp., Ameren Corp., Avista Corp., Black Hills Corp., CenterPoint Energy, Inc., CMS Energy Corp., Evergy, Inc., Eversource Energy, Hawaiian Electric Industries, Inc., IDACORP, Inc., MDU Resources Group, Inc., NiSource Inc., OGE Energy Corp., Pinnacle West Capital Corp., Portland General Electric Co., PPL Corp., Public Service Enterprise Group, Southwest Gas Holdings Inc., and WEC Energy Group, Inc. The market data provides market reference points at the 25th, 50th and 75th percentiles for each executive officer’s compensation components and total compensation. Generally, total aggregate compensation that falls within 15% of the median market reference point is considered to be at target. The aggregate total targeted compensation for all named executive officers fell within 15% of the applicable market reference point in 2023.

ALLIANT ENERGY | 2024 Proxy Statement | 36

COMPENSATION DISCUSSION AND ANALYSIS

Key Compensation Governance and Pay Practices

Our executive compensation program emphasizes best practices in compensation design and governance practices, including:

Regular reviews of the program by the Compensation and Personnel Committee	Double-trigger change in control provisions in our severance agreements and long-term equity awards
Strong linkage of compensation to achievement of financial and operational goals	No hedging or pledging of Company stock
Performance metrics that encourage achievement of both absolute growth and relative growth	Stock ownership guidelines for executive officers
Dividends paid on equity awards only if performance targets are met or vesting is completed	Limited perquisites for our executive officers
All long-term equity awards settle in Company stock	Maximum multiplier for change in control cash severance benefit no greater than 2.99
Clawback policy that applies to our annual and long-term incentive pay plans	No tax gross-up provisions in our change in control agreements

Executive Stock Ownership Requirements

We require executives of Alliant Energy to own a certain number of shares of common stock to further align the executives’ interests with those of our shareowners. The stock ownership guidelines are:

Officer Level	Stock Ownership Guideline
Chief Executive Officer/Executive Chairman	6 times base salary
President	4 times base salary
Executive Vice President	3.5 times base salary
Senior Vice President	3 times base salary
Vice President	1.5 times base salary

The required number of shares for each executive is determined by taking the preceding multiples of the executive’s base salary and dividing that amount by the closing price of our common stock as of: (i) January 2, 2024, (ii) the date of hire, or (iii) the date of promotion to a higher level of ownership requirement, whichever is later. We round that number to the nearest 500-share increment. The number of shares an executive is required to hold will not change unless the executive is promoted. Setting the required number of shares this way mitigates the effect of short-term volatility on compliance caused by changes in our stock price and by changes in salary.

Shares held outright, vested restricted stock units, earned performance shares, earned performance restricted stock units, unvested restricted stock units that vest based solely on the passage of time, shares held in our AEDCP and shares held in the Alliant Energy Corporation 401(k) Savings Plan count toward the stock ownership requirement. Unearned performance restricted stock units and unearned performance shares do not count for this purpose.

Executives have five years from the date of their first long-term equity grants after the later of their hire date, or the date they were promoted into a position with a higher multiple, to achieve their goals. Executives who have not met their stock ownership level after five years are required to retain 100% of the after-tax value of vested long-term equity awards until the share ownership requirement is met. The Company has not issued any stock options so there is no requirement to hold stock options after exercise. Our CEO retains the right to grant special dispensation for hardship, promotions or new hires.

All of our current named executive officers who have held their current positions for five years are in compliance with the stock ownership guidelines. The named executive officers who have been in their positions for less than five years, including our current CEO, are on track to achieve the above ownership goals. The shares owned by our named executive officers are shown in the Ownership of Voting Securities table.

Clawback Policy

The Compensation and Personnel Committee adopted a clawback policy that provides that the Company will recover erroneously awarded incentive-based compensation in the event of an accounting restatement. The policy applies to incentive compensation received by current and former executive officers. It is triggered by an accounting restatement due to the Company’s material noncompliance with any financial reporting requirement under the securities laws. The Company must reasonably promptly recoup the amount of incentive-based compensation that exceeds the amount that would have been received by the executive officer had it been determined based on the restated amounts. Incentive compensation received for the three years preceding the restatement is subject to recoupment under the policy, subject to limited exceptions. This policy is intended to comply with the Exchange Act, rules and regulations promulgated by the Securities and Exchange Commission, and Nasdaq listing standards.

ALLIANT ENERGY | 2024 Proxy Statement | 37

COMPENSATION DISCUSSION AND ANALYSIS

The Compensation and Personnel Committee previously adopted a clawback policy for executive officers that applies to all cash and equity-based incentive compensation to the extent not superseded by the clawback policy discussed above. Under the previous clawback policy, the committee will recoup compensation paid under the Company’s cash and equity incentive plans if it determines that such compensation was based on the achievement of financial or other results that were subsequently restated due to material noncompliance of the Company with any financial reporting requirement under the federal securities laws, and due in whole or in part to gross negligence, intentional misconduct or fraud of a current or former executive officer. If, in the committee’s view, the incentive-based compensation would have been materially lower if it had been based on the restated results, the committee will, to the extent permitted by applicable law, seek recoupment from that executive officer of any excess incentive compensation.

Prohibition on Hedging and Pledging

We prohibit the use of any hedging or similar transactions related to our shares by our executive officers and directors. We prohibit all insiders from trading in puts, calls, options or other derivative securities related to the Company’s securities. Other hedging transactions, such as short sales, zero-cost collars, prepaid variable forward sale contracts, equity swaps or similar transactions are also prohibited. Insiders are further prohibited from pledging Company securities. Insiders include all executive officers, all members of the Board of Directors and designated employees who receive material nonpublic information in the regular course of their duties.

Compensation and Personnel Committee Risk Assessment

In December 2023, the Compensation and Personnel Committee reviewed an assessment presented by management of our general compensation policies and practices for all employees to evaluate whether risks arising from these policies and practices were reasonably likely to have a material adverse effect on us. Based on this assessment, the committee concluded that our compensation policies and practices are not reasonably likely to have a material adverse effect on the Company and did not recommend or implement any material changes. The committee believes that the following features of our policies and practices serve to mitigate material risks arising from our compensation policies and practices:

•    A mix of annual and long-term incentive-based awards to provide an appropriate balance of short- and long-term risk and reward horizons

•    A variety of performance metrics for incentive awards to avoid excessive focus on a single measure of performance

•    Caps on incentive awards to reduce incentives to take short-term or inappropriately risky measures to increase payouts in any given year

•    Review of our compensation programs for reasonableness by our state utility commissions to mitigate risk

•    Clawback policies that provide us with the ability to recoup annual and long-term incentive awards under appropriate circumstances

•    Stock ownership requirements for executives, including our named executive officers, that help focus our executives on long-term stock price appreciation and sustainability

•    Robust compensation governance practices

Role of Tax Considerations

Section 162(m) of the tax code limits the tax deductibility of compensation paid to our CEO and certain other executive officers to $1 million per person in any taxable year.

The Compensation and Personnel Committee, consistent with past practice, retains the flexibility and discretion to authorize compensation that will not be deductible. This flexibility is necessary to achieve elements of the Company’s success that are in the best long-term interests of the Company and its shareowners, such as attracting and retaining talented executives and rewarding achievement of key corporate goals.

Response to Non-Binding 2023 Say-on-Pay Shareowner Vote

At Alliant Energy’s 2023 Annual Meeting of Shareowners, shareowners approved the say-on-pay proposal with more than 95% of the votes cast in favor of the proposal. The say-on-pay proposal is an advisory, non-binding resolution relating to the compensation of our named executive officers. We interpret the voting results as support that our executive compensation program and practices are reasonable and well aligned with shareowners’ interests. Notwithstanding this vote of confidence expressed by our shareowners, the Compensation and Personnel Committee and management continue to review the Company’s executive compensation program and related disclosure with the assistance of outside compensation consultants and outside counsel to identify any potential changes that might augment shareowner value.

CONCLUSION

The Compensation and Personnel Committee is provided with appropriate information and reviews all components of our CEO’s and other executive officers’ compensation. Based on this information, the committee seeks to implement executive compensation that is appropriately tied to the performance of the Company and executives on behalf of shareowners, employees and customers.

ALLIANT ENERGY | 2024 Proxy Statement | 38

COMPENSATION AND PERSONNEL COMMITTEE REPORT

COMPENSATION AND PERSONNEL COMMITTEE REPORT

The Compensation and Personnel Committees of the Boards of Directors of the Company, IPL and WPL have reviewed and discussed the Compensation Discussion and Analysis with our management. Based on this review and discussion, the committees recommended to the respective Boards of Directors that the Compensation Discussion and Analysis be included in this Proxy Statement and incorporated by reference in our Annual Report on Form 10-K for the year ended December 31, 2023, for filing with the Securities and Exchange Commission.

COMPENSATION AND PERSONNEL COMMITTEE

Patrick E. Allen (Chair)

Ignacio A. Cortina

Stephanie L. Cox

Michael D. Garcia

ALLIANT ENERGY | 2024 Proxy Statement | 39

EXECUTIVE COMPENSATION

EXECUTIVE COMPENSATION

SUMMARY COMPENSATION TABLE

The table below summarizes the compensation paid to or earned by our named executive officers for 2023, and, where applicable, 2022 and 2021.

Name and Principal Position	Year	Salary ($)(1)	Bonus ($) (2)	Stock Awards ($)(3)	Option Awards ($)	Non-Equity Incentive Plan Compensation ($)(1)(4)	Change in Pension Value and Non-qualified Deferred Compensation Earnings ($)(5)	All Other Compensation($)(6)	Total ($)
John O. Larsen: Board Chair and Chief Executive Officer of Alliant Energy; Board Chair of IPL and WPL	2023	$1,130,247	$0	$5,191,716	$0	$1,444,206	$1,354,440	$589,173	$9,709,782
	2022	$1,085,000	$0	$4,193,783	$0	$1,528,398	$3,707	$476,089	$7,286,977
	2021	$1,024,904	$0	$3,776,810	$0	$1,511,747	$3,746,424	$389,375	$10,449,260
Lisa M. Barton: President and Chief Operating Officer of Alliant Energy; Chief Executive Officer of IPL and WPL (7)	2023	$698,385	$1,700,000	$2,545,901	$0	$638,138	$4	$130,299	$5,712,727
Robert J. Durian: Executive Vice President and Chief Financial Officer	2023	$645,385	$0	$1,521,461	$0	$473,200	$22,608	$196,598	$2,859,252
	2022	$606,539	$0	$1,233,679	$0	$570,228	$1,934	$168,036	$2,580,416
	2021	$565,154	$0	$1,027,048	$0	$543,459	$38,187	$155,887	$2,329,735
Raja Sundararajan: Executive Vice President (7)	2023	$334,616	$0	$1,036,042	$0	$409,500	$0	$65,900	$1,846,058
David A. de Leon: Senior Vice President and President of WPL	2023	$438,846	$0	$470,068	$0	$260,260	$24,000	$84,305	$1,277,479
	2022	$426,923	$0	$424,148	$0	$301,473	$0	$74,287	$1,226,831
	2021	$390,288	$0	$325,744	$0	$250,088	$0	$63,490	$1,029,610
Terry L. Kouba: Senior Vice President and President of IPL	2023	$438,846	$0	$470,068	$0	$260,260	$12,081	$88,755	$1,270,010
	2022	$426,923	$0	$424,148	$0	$301,473	$80	$74,189	$1,226,813
	2021	$390,288	$0	$325,744	$0	$250,088	$141	$65,039	$1,031,300

(1)    The amounts shown in this column include any amounts deferred by the named executive officers under the Alliant Energy Deferred Compensation Plan. See 2023 Non-qualified Deferred Compensation.

(2) In 2023, Ms. Barton was provided with a cash signing bonus of $1.7 million when she was appointed President and COO of Alliant Energy and CEO of IPL and WPL. This bonus was provided in consideration of relocation costs, any foregone compensation from her previous employer, and was important to our successful recruitment of Ms. Barton in a competitive market for top talent in our industry. The signing bonus is subject to repayment terms in the event that Ms. Barton terminates her employment within three years of joining the Company.

(3)    The amounts in this column reflect the aggregate grant date fair value of performance shares, performance restricted stock units and restricted stock units granted pursuant to our 2020 Omnibus Incentive Plan, computed in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 18, or FASB ASC Topic 718.

ALLIANT ENERGY | 2024 Proxy Statement | 40

EXECUTIVE COMPENSATION

A discussion of the assumptions used in calculating the award values may be found in Note 13(b) to our 2023 audited financial statements contained in our Annual Report on Form 10-K. For the performance shares, the grant date fair value is based on the probable outcome of the performance conditions, consistent with the estimate of aggregate compensation cost to be recognized over the three-year performance period determined as of the grant date under FASB ASC Topic 718, excluding the effect of estimated forfeitures.

The following represents the breakdown of the 2023 grant date fair values of performance shares at target and at maximum, respectively, for each named executive officer:

Name	Grant Date Fair Value of  Performance Shares (Target)	Grant Date Fair Value of  Performance Shares (Maximum)
John O. Larsen	$1,876,026	$3,752,052
Lisa M. Barton	$937,261	$1,874,522
Robert J. Durian	$549,784	$1,099,568
Raja Sundararajan	$373,167	$746,334
David A. de Leon	$169,880	$339,760
Terry L. Kouba	$169,880	$339,760

The following represents the breakdown of the 2023 grant date fair value of performance restricted stock units at target and at maximum, respectively, for each named executive officer for net income performance:

Name	Grant Date Fair Value of  Performance Restricted Stock Units (Target)	Grant Date Fair Value of  Performance Restricted Stock Units (Maximum)
John O. Larsen	$1,785,392	$3,570,784
Lisa M. Barton	$866,226	$1,732,452
Robert J. Durian	$523,223	$1,046,446
Raja Sundararajan	$356,949	$713,898
David A. de Leon	$161,672	$323,344
Terry L. Kouba	$161,672	$323,344

The following represents the breakdown of the 2023 grant date fair value of performance restricted stock units at target and at maximum, respectively, for each named executive officer for diversity performance:

Name	Grant Date Fair Value of  Performance Restricted Stock Units (Target)	Grant Date Fair Value of  Performance Restricted Stock Units (Maximum)
John O. Larsen	$255,041	$510,082
Lisa M. Barton	$123,710	$247,420
Robert J. Durian	$74,716	$149,432
Raja Sundararajan	$50,970	$101,940
David A. de Leon	$23,051	$46,102
Terry L. Kouba	$23,051	$46,102

(4)    The 2023 amounts in this column reflect cash amounts for short-term incentive pay received by the named executive officers with respect to services performed in 2023 that were paid in 2024.

(5)    The 2023 amounts in this column reflect: (a) the actuarial increase in the present value of each named executive officer’s benefits under all pension plans established by us, determined using the assumptions and methods set forth in footnote (3) to the 2023 Pension Benefits table, which may include amounts that the named executive officer is not currently entitled to receive because such amounts are not yet vested, and (b) amounts representing above market interest on non-qualified deferred compensation.

ALLIANT ENERGY | 2024 Proxy Statement | 41

EXECUTIVE COMPENSATION

The following represents the breakdown for 2023 for each of the change in pension value and the above market interest on non-qualified deferred compensation, respectively, for each named executive officer:

Name	Change in Pension Value	Above Market Non-qualified  Deferred Compensation Earnings
John O. Larsen	$1,351,000	$3,440
Lisa M. Barton	$0	$4
Robert J. Durian	$20,000	$2,608
Raja Sundararajan	$0	$0
David A. de Leon	$24,000	$0
Terry L. Kouba	$12,000	$81

The changes in the actuarial present values of the named executive officers’ pension benefits do not constitute cash payments to the named executive officers.

(6)    The following table provides details for the amounts reported under the All Other Compensation column for 2023.

Name	Perquisites and Other Personal Benefits(a)	Registrant  Contributions to  Defined Contribution Plans(b)	Life Insurance Premiums	Dividends(c)	Other Payments(d)
John O. Larsen	$32,344	$92,338	$11,484	$453,007	$0
Lisa M. Barton	$0	$59,971	$4,480	$65,848	$0
Robert J. Durian	$0	$64,385	$2,528	$129,685	$0
Raja Sundararajan	$0	$22,154	$589	$17,407	$25,750
David A. de Leon	$0	$37,558	$4,814	$41,933	$0
Terry L. Kouba	$0	$37,558	$9,264	$41,933	$0

(a)    Mr. Larsen received perquisites and other personal benefits comprised of an annual physical exam, security services, personal use of aircraft, and executive long-term disability insurance. None of the other named executive officers received perquisites and other personal benefits in the aggregate amount of $10,000 or more in 2023.

(b)    Matching contributions to the Alliant Energy Corporation 401(k) Savings Plan, employer contributions to the Alliant Energy Deferred Compensation Plan, employer contributions based on age and service to the 401(k) Savings Plan accounts and employer contributions to the Alliant Energy Excess Retirement Plan.

(c)    Dividends and dividend equivalents earned in 2023 on unvested performance shares, performance restricted stock units and restricted stock units are reinvested and paid only at the time performance and/or vesting conditions are satisfied.

(d) Mr. Sundararajan received $17,250 of relocation expense, and a tax reimbursement of $8,500 related to relocation expenses.

(7) Ms. Barton and Mr. Sundararajan were not named executive officers in 2021 or 2022.

2023 CEO Pay Ratio

As required by SEC rules, we are providing the following information based on reasonable estimates. For 2023, the median of the annual total compensation of all employees (other than CEO) of the Company was $173,346.

The annual total compensation of Alliant Energy’s CEO, as reported in the Summary Compensation Table for 2023 above, was $9,709,782. The ratio of the annual total compensation of Alliant Energy’s CEO to the median of the annual total compensation of all employees for 2023 was 56 to 1.

In 2023, both Mr. Larsen and Ms. Barton served as CEO of IPL and WPL. We used Ms. Barton’s annualized compensation to calculate the CEO pay ratio for IPL and WPL. To calculate Ms. Barton’s annualized compensation, we used the 2023 values reflected in the Summary Compensation Table except for salary where we used the annualized salary of $825,000. For purposes of calculating the IPL and WPL CEO pay ratio only, the total CEO compensation used was $5,839,343. The ratio of the annual total compensation of IPL’s and WPL’s CEO to the median of the annual total compensation of all employees for 2023 was 34 to 1.

To identify the median employee from our employee population in 2023, we compared the amount of salary and wages of our employees as reflected in our payroll records as reported to the IRS on Form W-2 for 2023. We used December 31, 2023 as the determination date. We did not consider annual equity awards in determining the median employee as such awards are not widely distributed to our employee population. We did not make any cost-of-living adjustments. We annualized the compensation of employees who were hired in 2023. Once we identified our median employee, we calculated that employee’s compensation for 2023 as though that compensation were being calculated for purposes of the Summary Compensation Table. We compared that compensation total with the 2023 compensation of the CEOs as described above.

ALLIANT ENERGY | 2024 Proxy Statement | 42

EXECUTIVE COMPENSATION

2023 GRANTS OF PLAN-BASED AWARDS

The following table sets forth information regarding all plan-based awards that we granted to our named executive officers in 2023.

Name	Grant Date	Estimated Possible Payouts Under Non-Equity Incentive Plan Awards(1)			Estimated Future Payouts Under Equity Incentive Plan Awards			All Other Stock Awards: Number of Shares of Stock or Units (#)	Grant Date Fair Value of Stock Awards ($)
		Threshold ($)	Target ($)	Maximum ($)	Threshold (#)	Target (#)	Maximum (#)
John O. Larsen	2/23/2023(2)				16,847	33,693	67,386		$1,876,026
	2/23/2023(3)				16,847	33,693	67,386		$1,785,392
	2/23/2023(4)				1,203	4,813	9,626		$255,041
	2/23/2023(5)							24,066	$1,275,257
		$317,408	$1,587,040	$3,174,080
Lisa M. Barton	2/27/2023(2)				8,417	16,833	33,666		$937,261
	2/27/2023(3)				8,417	16,833	33,666		$866,226
	2/27/2023(4)				601	2,404	4,808		$123,710
	2/27/2023(5)							12,023	$618,704
		$140,250	$701,250	$1,402,500
Robert J. Durian	2/23/2023(2)				4,937	9,874	19,748		$549,784
	2/23/2023(3)				4,937	9,874	19,748		$523,223
	2/23/2023(4)				353	1,410	2,820		$74,716
	2/23/2023(5)							7,053	$373,738
		$104,000	$520,000	$1,040,000
Raja Sundararajan	6/12/2023(2)				3,351	6,702	13,404		$373,167
	6/12/2023(3)				3,351	6,702	13,404		$356,949
	6/12/2023(4)				239	957	1,914		$50,970
	6/12/2023(5)							4,787	$254,956
		$90,000	$450,000	$900,000
David A. de Leon	2/23/2023(2)				1,526	3,051	6,102		$169,880
	2/23/2023(3)				1,526	3,051	6,102		$161,672
	2/23/2023(4)				109	435	870		$23,051
	2/23/2023(5)							2,179	$115,465
		$57,200	$286,000	$572,000
Terry L. Kouba	2/23/2023(2)				1,526	3,051	6,102		$169,880
	2/23/2023(3)				1,526	3,051	6,102		$161,672
	2/23/2023(4)				109	435	870		$23,051
	2/23/2023(5)							2,179	$115,465
		$57,200	$286,000	$572,000

(1)    The amounts shown represent the threshold, target and maximum awards that could have been earned under our EXSTIP Plan for 2023 as described more fully under Compensation Discussion and Analysis — How We Pay Named Executive Officers — Short-Term (Annual) Incentive Pay. The threshold payment level was 20% of the target amount. The maximum payment level was 200% of the target amount. Payments earned for 2023 are shown in the Non-Equity Incentive Plan Compensation column of the Summary Compensation Table.

(2)    The amounts shown represent the threshold, target and maximum amounts of performance shares that were awarded in 2023 to the named executive officers under our 2020 Omnibus Incentive Plan as described more fully under Compensation Discussion and Analysis — How We Pay Named Executive Officers — Long-Term Equity Awards. The threshold amount is shown at 50% of the target amount. The maximum amount is 200% of the target amount. For the performance shares, the grant date fair value is

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EXECUTIVE COMPENSATION

based on the probable outcome of the performance conditions, consistent with the estimate of aggregate compensation cost to be recognized over the performance period determined as of the grant date pursuant to FASB ASC Topic 718, excluding the effect of estimated forfeitures. For the performance shares granted in 2023, the grant date fair value, as determined by FASB ASC Topic 718, is $55.68. Performance shares granted in 2023 accumulate dividend equivalents on the same basis as shares of our common stock, but dividends are not paid until performance targets and vesting requirements are met.

(3)    The amounts shown represent the threshold, target and maximum amounts of performance restricted stock units (Net Income) that were awarded in 2023 to the named executive officers under our 2020 Omnibus Incentive Plan as described more fully under Compensation Discussion and Analysis — How We Pay Named Executive Officers — Long-Term Equity Awards. The threshold amount is shown at 50% of the target amount. The maximum amount is 200% of the target amount. For the performance restricted stock units, the grant date fair value, as determined by the closing price of our common stock on the grant date, is $52.99 for the grants on February 23, 2023, $51.46 for the grants on February 27, 2023, and $53.26 for the grants on June 12, 2023. Performance restricted stock units granted in 2023 accumulate dividend equivalents on the same basis as shares of our common stock, but dividends are not paid until performance targets and vesting requirements are met.

(4) The amounts shown represent the threshold, target and maximum amounts of performance restricted stock units (Diversity) that were awarded in 2023 to the named executive officers under our 2020 Omnibus Incentive Plan as described more fully under Compensation Discussion and Analysis — How We Pay Named Executive Officers — Long-Term Equity Awards. The threshold amount is shown at 25% of the target amount. The maximum amount is 200% of the target amount. For the performance restricted stock units, the grant date fair value, as determined by the closing price of our common stock on the grant date, is $52.99 for the grants on February 23, 2023, $51.46 for the grants on February 27, 2023, and $53.26 for the grants on June 12, 2023. Performance restricted stock units granted in 2023 accumulate dividend equivalents on the same basis as shares of our common stock, but dividends are not paid until performance targets and vesting requirements are met.

(5)    The amounts shown represent the number of restricted stock units that were awarded in 2023 to the named executive officers under our 2020 Omnibus Incentive Plan as described more fully under Compensation Discussion and Analysis — How We Pay Named Executive Officers — Long-Term Equity Awards. For the restricted stock units, the grant date fair value, as determined by the closing price of our common stock on the grant date, is $52.99 for the grants on February 23, 2023, $51.46 for the grants on February 27, 2023, and $53.26 for the grants on June 12, 2023. Restricted stock units granted in 2023 accumulate dividend equivalents on the same basis as shares of our common stock, but dividends are not paid until the restricted stock units are fully vested.

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EXECUTIVE COMPENSATION

2023 OUTSTANDING EQUITY AWARDS AT FISCAL YEAR-END

The following table sets forth information on outstanding unvested equity awards held by our named executive officers on December 31, 2023. No stock options are outstanding.

	Stock Awards
Name	Number of Shares or Units of Stock That Have Not Vested (#)(1)	Market Value of Shares or Units of Stock That Have Not Vested ($)(1)	Equity Incentive Plan Awards: Number of Unearned Shares, Units or Other Rights That Have Not Vested (#)(1)	Equity Incentive Plan Awards: Market or Payout Value of Unearned Shares, Units or Other Rights That Have Not Vested ($)(1)
John O. Larsen			55,621	$2,853,357	(2)
			69,191	$3,549,498	(3)
			55,621	$2,853,357	(4)
			69,191	$3,549,498	(5)
			7,944	$407,527	(6)
			9,884	$507,049	(7)
	19,864	$1,019,023			(8)
	24,711	$1,267,674			(9)
Lisa M. Barton			34,568	$1,773,338	(3)
			34,568	$1,773,338	(5)
			4,937	$253,268	(7)
	12,345	$633,299			(9)
Robert J. Durian			16,362	$839,371	(2)
			20,277	$1,040,210	(3)
			16,362	$839,371	(4)
			20,277	$1,040,210	(5)
			2,337	$119,888	(6)
			2,896	$148,565	(7)
	5,843	$299,746			(8)
	7,242	$371,515			(9)
Raja Sundararajan			13,649	$700,194	(3)
			13,649	$700,194	(5)
			1,949	$99,984	(7)
	4,874	$250,036			(9)
David A. de Leon			5,626	$288,614	(2)
			6,265	$321,395	(3)
			5,626	$288,614	(4)
			6,265	$321,395	(5)
			802	$41,143	(6)
			893	$45,811	(7)
	2,009	$103,062			(8)
	2,237	$114,758			(9)
Terry L. Kouba			5,626	$288,614	(2)
			6,265	$321,395	(3)
			5,626	$288,614	(4)
			6,265	$321,395	(5)
			802	$41,143	(6)
			893	$45,811	(7)
	2,009	$103,062			(8)
	2,237	$114,758			(9)

(1)    The share or unit values in the table include credited dividend equivalents, which will be paid only if the vesting criterion is met and the underlying award is paid out. The dollar values in the table are calculated by using the closing price of our common stock of $51.30 on December 29, 2023.

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(2)    Performance shares granted on February 17, 2022. Vesting occurs if the performance criterion is met in year 3. The values in the table assume maximum level performance.

(3)    Performance shares granted on February 23, 2023 except those granted to Ms. Barton on February 27, 2023 and to Mr. Sundararajan on June 12, 2023. Vesting occurs if the performance criterion is met in year 3. The values in the table assume maximum level performance.

(4)    Performance restricted stock units (Net Income) granted on February 17, 2022. Vesting occurs if the performance criterion is met in year 3. The values in the table assume maximum level performance.

(5)    Performance restricted stock units (Net Income) granted on February 23, 2023 except those granted to Ms. Barton on February 27, 2023 and to Mr. Sundararajan on June 12, 2023. The values in the table assume maximum level performance.

(6) Performance restricted stock units (Diversity) granted on February 17, 2022. Vesting occurs if the performance criterion is met in year 3. The values in the table assume maximum level performance.

(7)    Performance restricted stock units (Diversity) granted on February 23, 2023 except those granted to Ms. Barton on February 27, 2023 and to Mr. Sundararajan on June 12, 2023. The values in the table assume maximum level performance.

(8)    Restricted stock units granted on February 17, 2022. Vesting occurs based on continuous service through year 3.

(9)    Restricted stock units granted on February 23, 2023 except those granted to Ms. Barton on February 27, 2023 and to Mr. Sundararajan on June 12, 2023. Vesting occurs based on continuous service through year 3.

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EXECUTIVE COMPENSATION

2023 OPTION EXERCISES AND STOCK VESTED

The following table shows a summary of the stock awards vested for our named executive officers during 2023. No stock options were exercised during 2023.

	Stock Awards
Name	Long-Term Equity Awards	Number of Shares Acquired on Vesting (#)	Value Realized on Vesting ($)(1)
John O. Larsen	Performance Shares	21,302	$1,031,017
	Performance Restricted Stock Units	59,646	$2,886,866
	Restricted Stock Units	26,084	$1,338,109
Lisa M. Barton	Performance Shares	0	$0
	Performance Restricted Stock Units	0	$0
	Restricted Stock Units	0	$0
Robert J. Durian	Performance Shares	5,792	$280,333
	Performance Restricted Stock Units	16,219	$785,000
	Restricted Stock Units	7,093	$363,871
Raja Sundararajan	Performance Shares	0	$0
	Performance Restricted Stock Units	0	$0
	Restricted Stock Units	0	$0
David A. de Leon	Performance Shares	1,837	$88,911
	Performance Restricted Stock Units	5,144	$248,970
	Restricted Stock Units	2,249	$115,374
Terry L. Kouba	Performance Shares	1,837	$88,911
	Performance Restricted Stock Units	5,144	$248,970
	Restricted Stock Units	2,249	$115,374

(1)    For performance shares granted for the 2021-2023 performance period, reflects an amount calculated by multiplying the number of vested performance shares, plus accumulated dividend equivalent units (including fractional amounts not shown), by the fair market value of our common stock on February 15, 2024 (the date the Compensation and Personnel Committee certified achievement of the performance goals for such performance shares) of $48.40. For performance restricted stock units granted for the 2021-2023 performance period, reflects an amount calculated by multiplying the number of vested performance restricted stock units, plus accumulated dividend equivalent units (including fractional amounts not shown), by the fair market value of our common stock on February 15, 2024 (the date the Compensation and Personnel Committee certified achievement of the performance goals for such performance restricted stock units) of $48.40. For restricted stock units granted for the 2021-2023 performance period, reflects an amount calculated by multiplying the number of vested shares of restricted stock units, plus accumulated dividend equivalent units (including fractional amounts not shown), by the fair market value of our common stock on December 29, 2023 of $51.30. Performance restricted stock units, performance shares, and restricted stock units are settled in shares only. Ms. Barton and Mr. Sundararajan joined the Company in 2023 and did not receive grants for the 2021-2023 performance period.

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EXECUTIVE COMPENSATION

2023 PENSION BENEFITS

Pension Benefits Table

The following table sets forth the number of years of credited service, the present value of accumulated benefits and payments during 2023 for each of our named executive officers under the Alliant Energy Cash Balance Pension Plan, the Alliant Energy Excess Retirement Plan, and the Alliant Energy Defined Benefit Supplemental Retirement Plan (DB SRP), which are each described below. The amounts shown for our named executive officers are estimates only and do not necessarily reflect the actual amounts that will be paid to them, which will only be known at the time that they become eligible for payment.

Name	Plan Name	Number of Years Credited Service (#)(2)	Present Value of Accumulated Benefit ($)(3)	Payments During 2023 ( $ )
John O. Larsen	Cash Balance Pension Plan	20.5	$537,000
	Excess Retirement Plan	35.9	$492,000
	DB SRP	35.9	$13,159,000
		Total	$14,188,000	$0
Lisa M. Barton(1)	Cash Balance Pension Plan	N/A	N/A
	Excess Retirement Plan	0.9	$18,000
	DB SRP	N/A	N/A
		Total	$18,000	$0
Robert J. Durian(1)	Cash Balance Pension Plan	15.9	$167,000
	Excess Retirement Plan	31.3	$271,000
	DB SRP	N/A	N/A
		Total	$438,000	$0
Raja Sundararajan(1)	Cash Balance Pension Plan	N/A	N/A
	Excess Retirement Plan	0.6	$1,000
	DB SRP	N/A	N/A
		Total	$1,000	$0
David A. de Leon(1)	Cash Balance Pension Plan	21.2	$376,000
	Excess Retirement Plan	36.6	$31,000
	DB SRP	N/A	N/A
		Total	$407,000	$0
Terry L. Kouba(1)	Cash Balance Pension Plan	27.4	$572,000
	Excess Retirement Plan	42.8	$55,000
	DB SRP	N/A	N/A
		Total	$627,000	$0

(1)    Ms. Barton, Mr. Durian, Mr. Sundararajan, Mr. de Leon and Mr. Kouba are not eligible for the DB SRP. They are eligible for the Excess Retirement Plan and, except for Ms. Barton and Mr. Sundararajan, the Cash Balance Pension Plan.

(2)    Years of credited service for the Cash Balance Pension Plan are less than the actual years of service of the officer because the Cash Balance Pension Plan was frozen in August 2008.

(3)    The following assumptions, among others, were used to calculate the present value of accumulated benefits: benefit commencement age is the earliest unreduced retirement age for the predominant plan (Mr. Larsen, Mr. Durian, and Mr. de Leon each at age 62 for the Cash Balance Pension Plan and Excess Retirement Plan, Mr. Kouba at age 65 for the Cash Balance Pension Plan and Excess Retirement Plan, Ms. Barton and Mr. Sundararajan each at age 65 for the Excess Retirement Plan, and Mr. Larsen at age 62 for the DB SRP); the benefit calculation date is December 31, 2023, consistent with our accounting measurement date for financial statement reporting purposes; the ASC 715 discount rate is 5.27% for the DB SRP, 5.43% for the Excess Retirement Plan, and 5.38% for the Cash Balance Pension Plan (compared to 5.53% for the DB SRP, 5.55% for the Excess Retirement Plan, and 5.53% for the Cash Balance Pension Plan in 2022); the post-retirement mortality assumption is based on the PRI-2012 mortality table with white collar adjustment and generational projection starting in 2012 using a modified Scale MP-2021 (same as used for ASC 715 valuations); the form of payment is 50% lump sum and 50% annuity for the Cash Balance Pension Plan and 100% lump sum for the Excess Retirement Plan; and the ASC 715 accounting valuation for the DB SRP

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anticipates payments in the form of a lump sum (for those that elected lump sum or installment) and the effective lump sum interest rate for valuation purposes is approximately 3.93% at year-end 2023.

Alliant Energy Cash Balance Pension Plan

A portion of our salaried employees, including certain of our named executive officers, are eligible to participate in the Alliant Energy Cash Balance Pension Plan that we maintain. The Cash Balance Pension Plan bases a participant’s defined benefit pension on the value of a hypothetical account balance. For individuals participating in the Cash Balance Pension Plan as of August 1, 1998, a starting account balance was created equal to the present value of the benefit accrued as of December 31, 1997, under the applicable prior benefit formula. In addition, such individuals received a special one-time transition credit amount equal to a specified percentage varying with age and multiplied by credited service and pay. For 1998 through August 2, 2008, participants received annual credits to the account equal to 5% of base pay (including certain incentive payments, pre-tax deferrals and other items). For 1998 through August 2, 2008, participants also received an interest credit on all prior accruals equal to 4%, plus a potential share of the gain on the investment return on Cash Balance Pension Plan assets for the year. We amended the Cash Balance Pension Plan’s interest crediting rate for 2009 and future years. The new interest crediting rate is equal to the annual percentage change in the consumer price index as of October each year, plus 3%.

Ms. Barton and Mr. Sundararajan are not eligible to participate in the Cash Balance Pension Plan. For Mr. Larsen, Mr. Durian, Mr. de Leon, and Mr. Kouba, estimated benefits under the applicable prior plan benefit formula are expected to be higher than under the Cash Balance Pension Plan formula, utilizing current assumptions. Therefore, their benefits are determined under the applicable prior plan benefit formula. To the extent benefits under the Cash Balance Pension Plan are limited by tax law, any excess will be paid under the Excess Retirement Plan described below. Cash Balance Pension Plan accruals ceased as of August 2, 2008. This freeze applies to both the 5% of base pay annual credits to the hypothetical account balance and to the grandfathered prior plan formulas. Subsequent to August 2, 2008, active participants receive enhanced benefits under the Alliant Energy Corporation 401(k) Savings Plan.

Pension benefits for Mr. Larsen and Mr. Durian are determined using the prior plan formula from the IES Industries pension plan. The prior plan formula provides retirement income based on years of service, final average compensation and Social Security covered compensation.

The monthly benefit formula for Mr. Larsen and Mr. Durian for service until the August 2, 2008 freeze date is A + B + C where: A = 1.05% of average monthly compensation for the number of years of service not in excess of 35; B = 0.50% of average monthly compensation in excess of Social Security covered compensation for the number of years of service not in excess of 35; and C = 1.38% of average monthly compensation for the number of years of service in excess of 35. Compensation generally is the salary amount reported in the Summary Compensation Table (subject to the limit in the tax code), with the final average compensation being calculated based on the three highest calendar years of such pay. The formula provides the basic benefit payable for the life of the participant. If the participant receives an alternative form of payment, then the monthly benefit would be reduced accordingly. Early retirement benefits are available after a participant reaches age 55, provided he has at least 15 years of service. Unreduced benefits are available at age 62. Benefits that commence prior to age 62 are reduced by a factor of not less than 5% per year.

Pension benefits for Mr. de Leon are determined using the prior plan formula from the WPL pension plan. The prior plan formula provides retirement income based on years of service, final average compensation and Social Security covered compensation.

The monthly benefit formula for Mr. de Leon for service until the August 2, 2008 freeze date is A - B x C where: A = 55% of average monthly compensation for the number of years of service not in excess of 30; B = 0.50% of average monthly compensation in excess of Social Security covered compensation; and C is credited service (up to 360 months) divided by 30. Compensation generally is the salary amount reported in the Summary Compensation Table (subject to the limit in the tax code), with the final average compensation being calculated based on the three highest calendar years of such pay. The formula provides the basic benefit payable for the life of the participant. If the participant receives an alternative form of payment, then the monthly benefit would be reduced accordingly. Early retirement benefits are available after a participant reaches age 55, provided he has at least five years of vesting service. Unreduced benefits are available at age 62. Benefits that commence prior to age 62 are reduced by a factor of not less than 5% per year.

Pension benefits for Mr. Kouba are determined using the prior plan formula from the IPC pension plan. The prior plan formula provides retirement income based on years of service and final average compensation.

The monthly benefit formula for Mr. Kouba for service until the August 2, 2008 freeze date is A + B where: A = 1.17% of average monthly compensation for the number of years of service not in excess of 35 and B = 0.35% of average monthly compensation in excess of Social Security covered compensation. Compensation generally is the salary amount reported in the Summary Compensation Table (subject to the limit in the tax code), with the final average compensation being calculated based on the three highest calendar years of such pay. The formula provides the basic benefit payable for the life of the participant. If the participant receives an alternative form of payment, then the monthly benefit would be reduced accordingly. Early retirement benefits are available after a participant reaches age 55, provided he has at least 5 years of vesting service. Unreduced benefits are available at age 62. Benefits that commence prior to age 62 are reduced by a factor of not less than 3% per year.

Alliant Energy Excess Retirement Plan

We maintain an unfunded Excess Retirement Plan that provides funds for payment of retirement benefits where an employee’s retirement benefits exceed statutory limits applicable to the tax-qualified plans. The Excess Retirement Plan provides an amount equal to the difference between (i) the actual pension benefit payable under the Cash Balance Pension Plan and our actual contributions

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based on age and service to the Alliant Energy Corporation 401(k) Savings Plan, and (ii) what such benefits and contributions would be if calculated without regard to any limitation imposed by the tax code on pension benefits or covered compensation.

Alliant Energy Supplemental Retirement Plan

We maintain a legacy DB SRP which provides additional retirement benefits if the executive remains with us until retirement, disability or death. The DB SRP is an unfunded, defined benefit retirement plan and was discontinued in 2008. Mr. Larsen participates in the DB SRP. Ms. Barton, Mr. Durian, Mr. Sundararajan, Mr. de Leon and Mr. Kouba do not participate in the DB SRP.

For Mr. Larsen, the DB SRP provides for payments in accordance with the formula A - (B + C + D) where: A = 50% of the participant’s average annual earnings (base salary plus annual incentive pay) for the highest paid three consecutive years out of the last 10 years of the participant’s employment; B = benefits payable to the officer from the officer’s defined benefit plan; C = the aggregate Company contributions based on age and service to the Alliant Energy Corporation 401(k) Savings Plan; and D = the Excess Retirement Plan. The normal retirement date under the DB SRP is age 62 with at least 10 years of service; early retirement is at age 55 with at least 10 years of service and five or more years of continuous DB SRP employment. If a participant retires prior to age 62, the payment under the DB SRP is reduced by approximately 5% per year for each year the participant’s retirement date precedes his or her normal retirement date. This early retirement reduction factor is applied prior to any other offsets (described as B, C, or D above). Payment of benefits under the DB SRP commences six months after the participant’s retirement.

At the timely election of the participant, benefits under the DB SRP will be made in a lump sum, in annual installments over a period of five years, or in monthly installments for 18 years. Participants made their elections in December 2008. Participants may change their form of payment once, provided that the new election is made at least 12 months prior to their retirement. If such an election is made, benefits under the DB SRP will not be paid for five years after they otherwise would have been. If the monthly benefit is selected, and the participant dies prior to receiving 12 years of payments, payments continue to any surviving spouse or dependent children, payable for the remainder of the 12-year period. If the five annual installments benefit is selected and the participant dies prior to receiving five annual payments, payments will continue to any surviving spouse or dependent children, payable for the remainder of the five-year period. If the participant dies while still employed by us, the designated beneficiary will receive a lump sum equal to the discounted value of retirement benefits for 12 years.

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EXECUTIVE COMPENSATION

2023 NON-QUALIFIED DEFERRED COMPENSATION

The table below sets forth certain information as of December 31, 2023, for our named executive officers with respect to the Alliant Energy Deferred Compensation Plan, which is described below.

Name	Executive Contributions in 2023 ($)(1)	Registrant Contributions in 2023 ($)(2)	Aggregate Earnings in 2023 ($)(3)	Aggregate Withdrawals/ Distributions in 2023 ($)	Aggregate Balance as of December 31, 2023 ($)(4)
John O. Larsen	$22,572	$13,374	$95,369	$0	$2,122,489
Lisa M. Barton	$31,731	$15,404	$2,900	$0	$34,631
Robert J. Durian	$64,385	$14,504	$419,997	$0	$2,608,087
Raja Sundararajan	$11,539	$0	$897	$0	$12,435
David A. de Leon	$0	$0	$0	$0	$0
Terry L. Kouba	$0	$0	$95,893	$0	$566,050

(1)    The amounts reported are also reported under the Salary and Non-Equity Incentive Plan Compensation columns, as applicable, in the Summary Compensation Table.

(2)    The amounts reported are also reported under the All Other Compensation column in the Summary Compensation Table and represent contributions earned in the last completed fiscal year but not credited until the following fiscal year.

(3)    The following portion of the amounts reported in this column, which represents above-market interest on deferred compensation, is reported under the Change in Pension Value and Non-qualified Deferred Compensation Earnings column in the Summary Compensation Table.

Name	Above-Market Interest on Deferred Compensation
John O. Larsen	$3,440
Lisa M. Barton	$4
Robert J. Durian	$2,608
Raja Sundararajan	N/A
David A. de Leon	N/A
Terry L. Kouba	$81

(4)    The following amounts included in this column for the Alliant Energy Deferred Compensation Plan also have been reported in the Total column of the Summary Compensation Table for 2022 and 2021.

Name	Reported for 2022	Reported for 2021
John O. Larsen	$34,456	$32,452
Lisa M. Barton	N/A	N/A
Robert J. Durian	$74,423	$68,947
Raja Sundararajan	N/A	N/A
David A. de Leon	N/A	N/A
Terry L. Kouba	N/A	N/A

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We maintain the Alliant Energy Deferred Compensation Plan (AEDCP) under which participants, including our current named executive officers, may defer up to 100% of base salary and annual incentive pay. Participants who have made the maximum allowed contribution to the Alliant Energy Corporation 401(k) Savings Plan may receive an additional credit from the Company to the AEDCP. The credit made in March 2023 was equal to 50% of A - B, where:

A = the lesser of (i) 8% of base salary for the plan year or (ii) the sum of the amounts (if any) contributed by the participant to the Alliant Energy Corporation 401(k) Savings Plan during the applicable year that were eligible for matching contributions under the Alliant Energy Corporation 401(k) Savings Plan, plus the amounts deferred by the participant during the applicable year under the AEDCP; and

B = the amount of any matching contributions under the Alliant Energy Corporation 401(k) Savings Plan on behalf of the participant for the applicable year.

The participant may elect to have his or her deferrals credited to an Interest Account, Equity Account, Company Stock Account or Mutual Fund Account. Deferrals and matching contributions to the Interest Account receive an annual return based on the 10-year Treasury Bond Rate plus 1.50%. Deferrals and matching contributions credited to the Equity Account are treated as invested in an S&P 500 index fund. Deferrals and matching contributions credited to the Mutual Fund Account are treated as invested in a mutual fund or other investment vehicle offered under the Alliant Energy Corporation 401(k) Savings Plan and selected by the participant. Deferrals and matching contributions credited to the Company Stock Account are treated as though invested in our common stock and are credited with dividend equivalents, which are treated as if reinvested. The shares of common stock identified as obligations under the AEDCP are held in a rabbi trust. Payments from the AEDCP due to death or retirement may be made in a lump sum or in annual installments for up to 10 years at the election of the participant. Payments from the AEDCP for any reason other than death or retirement are made in a lump sum. Participants in the AEDCP are certain members of management or highly compensated employees under ERISA, and include all our current named executive officers except for Mr. de Leon.

We maintain a frozen legacy deferred compensation plan (the IES Deferred Compensation Plan), in which Mr. Larsen has a frozen account balance in the amount of $48,325 as of December 31, 2023. An interest credit is provided for the balance in the account at an annual rate of 9%. This plan was frozen on April 21,1998, and since then, no amounts have been deferred to the account.

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2023 POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

Tables

The following tables describe potential payments and benefits under our compensation and benefit plans and arrangements to which our named executive officers would be entitled upon termination of employment and/or a change in control of our Company. The estimated amount of compensation payable to each of our named executive officers in each situation is listed in the following tables assuming that the termination and/or change in control of our Company occurred on December 29, 2023, the last business day of our last completed fiscal year, and that our common stock is valued at $51.30, which was the closing market price for our common stock on that date. The actual amount of payments and benefits can only be determined at the time of such a termination or change in control and therefore the actual amounts will vary from the estimated amounts in the following tables. Descriptions of the circumstances that would trigger payments or benefits to our named executive officers, the method under which such payments and benefits are determined under the circumstances, the material conditions and obligations applicable to the receipt of payments or benefits, and other material factors regarding such agreements and plans, as well as other material assumptions that we have made in calculating the estimated compensation, follow these tables.

John O. Larsen	Death	Disability	Involuntary Termination Without Cause	Retirement	Change in Control and Termination Without Cause or for Good Reason	Change in Control Without Termination
Triggered Payouts
Cash Termination Payment	$0	$0	$1,133,600	$0	$8,134,714	$0
Life, Medical, Dental Insurance Continuation	$0	$0	$13,479	$0	$67,869	$0
Lump Sum SRP	$0	$0	$0	$0	$0	$0
Unearned Restricted Stock Units	$2,286,697	$2,286,697	$610,278	$2,286,697	$610,278	$610,278
Unearned Performance Restricted Stock Units	$3,658,717	$3,658,717	$1,763,027	$3,658,717	$1,763,027	$1,763,027
Unearned Performance Shares	$3,201,428	$3,201,428	$1,542,694	$3,201,428	$1,542,694	$1,542,694
Outplacement Services	$0	$0	$10,000	$0	$113,360	$0
Legal and Accounting Advisor Services	$0	$0	$0	$0	$10,000	$0
Total Pre-Tax Benefit	$9,146,842	$9,146,842	$5,073,078	$9,146,842	$12,241,942	$3,915,999

Lisa M. Barton	Death	Disability	Involuntary Termination Without Cause	Retirement	Change in Control and Termination Without Cause or for Good Reason	Change in Control Without Termination
Triggered Payouts
Cash Termination Payment	$0	$0	$825,000	$0	$3,052,500	$0
Life, Medical, Dental Insurance Continuation	$0	$0	$8,086	$0	$36,028	$0
Lump Sum SRP	$0	$0	$0	$0	$5,000	$0
Unearned Restricted Stock Units	$633,299	$633,299	$216,976	$633,299	$216,976	$216,976
Unearned Performance Restricted Stock Units	$1,013,303	$1,013,303	$337,759	$1,013,303	$337,759	$337,759
Unearned Performance Shares	$886,669	$886,669	$295,539	$886,669	$295,539	$295,539
Outplacement Services	$0	$0	$10,000	$0	$82,500	$0
Legal and Accounting Advisor Services	$0	$0	$0	$0	$10,000	$0
Total Pre-Tax Benefit	$2,533,271	$2,533,271	$1,693,360	$2,533,271	$4,036,302	$850,274

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EXECUTIVE COMPENSATION

Robert J. Durian	Death	Disability	Involuntary Termination Without Cause	Retirement	Change in Control and Termination Without Cause or for Good Reason	Change in Control Without Termination
Triggered Payouts
Cash Termination Payment	$0	$0	$650,000	$0	$2,340,000	$0
Life, Medical, Dental Insurance Continuation	$0	$0	$8,407	$0	$33,679	$0
Lump Sum SRP	$0	$0	$0	$0	$0	$0
Unearned Restricted Stock Units	$671,261	$671,261	$179,043	$671,261	$179,043	$179,043
Unearned Performance Restricted Stock Units	$1,074,018	$1,074,018	$517,874	$1,074,018	$517,874	$517,874
Unearned Performance Shares	$939,791	$939,791	$453,133	$939,791	$453,133	$453,133
Outplacement Services	$0	$0	$10,000	$0	$65,000	$0
Legal and Accounting Advisor Services	$0	$0	$0	$0	$10,000	$0
Total Pre-Tax Benefit	$2,685,070	$2,685,070	$1,818,457	$2,685,070	$3,598,729	$1,150,050

Raja Sundararajan	Death	Disability	Involuntary Termination Without Cause	Retirement	Change in Control and Termination Without Cause or for Good Reason	Change in Control Without Termination
Triggered Payouts
Cash Termination Payment	$0	$0	$600,000	$0	$2,100,000	$0
Life, Medical, Dental Insurance Continuation	$0	$0	$4,208	$0	$15,808	$0
Lump Sum SRP	$0	$0	$0	$0	$0	$0
Unearned Restricted Stock Units	$250,036	$250,036	$85,666	$250,036	$85,666	$85,666
Unearned Performance Restricted Stock Units	$400,089	$400,089	$133,380	$400,089	$133,380	$133,380
Unearned Performance Shares	$350,097	$350,097	$116,708	$350,097	$116,708	$116,708
Outplacement Services	$0	$0	$10,000	$0	$60,000	$0
Legal and Accounting Advisor Services	$0	$0	$0	$0	$10,000	$0
Total Pre-Tax Benefit	$1,000,222	$1,000,222	$949,962	$1,000,222	$2,521,562	$335,754

David A. de Leon	Death	Disability	Involuntary Termination Without Cause	Retirement	Change in Control and Termination Without Cause or for Good Reason	Change in Control Without Termination
Triggered Payouts
Cash Termination Payment	$0	$0	$440,000	$0	$1,452,000	$0
Life, Medical, Dental Insurance Continuation	$0	$0	$9,065	$0	$39,280	$0
Lump Sum SRP	$0	$0	$0	$0	$0	$0
Unearned Restricted Stock Units	$217,820	$217,820	$57,113	$217,820	$57,113	$57,113
Unearned Performance Restricted Stock Units	$348,483	$348,483	$171,137	$348,483	$171,137	$171,137
Unearned Performance Shares	$305,005	$305,005	$149,745	$305,005	$149,745	$149,745
Outplacement Services	$0	$0	$10,000	$0	$44,000	$0
Legal and Accounting Advisor Services	$0	$0	$0	$0	$10,000	$0
Total Pre-Tax Benefit	$871,308	$871,308	$837,060	$871,308	$1,923,275	$377,995

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EXECUTIVE COMPENSATION

Terry L. Kouba	Death	Disability	Involuntary Termination Without Cause	Retirement	Change in Control and Termination Without Cause or for Good Reason	Change in Control Without Termination
Triggered Payouts
Cash Termination Payment	$0	$0	$440,000	$0	$1,452,000	$0
Life, Medical, Dental Insurance Continuation	$0	$0	$9,065	$0	$48,179	$0
Lump Sum SRP	$0	$0	$0	$0	$0	$0
Unearned Restricted Stock Units	$217,820	$217,820	$57,113	$217,820	$57,113	$57,113
Unearned Performance Restricted Stock Units	$348,483	$348,483	$171,137	$348,483	$171,137	$171,137
Unearned Performance Shares	$305,005	$305,005	$149,745	$305,005	$149,745	$149,745
Outplacement Services	$0	$0	$10,000	$0	$44,000	$0
Legal and Accounting Advisor Services	$0	$0	$0	$0	$10,000	$0
Total Pre-Tax Benefit	$871,308	$871,308	$837,060	$871,308	$1,932,174	$377,995

Change in Control Agreements

We currently have in effect Key Executive Employment and Severance Agreements (KEESAs) with all our named executive officers. The KEESAs provide that each executive officer who is a party thereto is entitled to benefits if, within a period of up to two years after a change in control of our Company (as defined below), or within 180 days prior thereto in connection with a change in control, the executive’s employment ends as a result of: (a) termination by us, other than by reason of death or disability or for cause (as defined below), or (b) termination by the officer for good reason (as defined below).

The KEESAs provide the following benefits in the event of a qualifying termination up to two years after a change of control, each of which is reflected in the tables above, assuming the maximum potential amounts payable pursuant to the terms of the KEESAs:

•outplacement services at a cost not to exceed 10% of the officer’s annual base salary

•continuation of life, medical and dental insurance coverage for up to two years

•full vesting of the officer’s accrued benefit under any SRP and in any defined contribution retirement plan such as the Excess Retirement Plan, and deemed satisfaction of any minimum years of service requirement under the SRP (the amounts shown in the tables above assume a lump sum form of payment under the SRP using the 2024 lump sum interest rate of 3.96% and a single life annuity or lump sum payment under our qualified Cash Balance Pension Plan and non-qualified Excess Retirement Plan using a lump sum interest rate for payment commencing in fiscal 2024 (i.e., IRS PPA lump sum segment interest rate of 5.77%, 6.14%, and 6.19%)), provided that the form and time for payment of benefits will be in accordance with the terms of the applicable plan

•payment under outstanding equity awards pursuant to the terms of the plan and the agreement under which the awards were granted

•cash termination payment of 2.99 times for the CEO and, for the other executive officers, two times the sum of (i) the executive officer’s annual base salary and (ii) the executive officer’s target annual incentive pay for the year in which the termination occurs (Cash Termination Payment), and

•reimbursement for up to $10,000 in legal or accounting advisor fees relating to the computation of cash amounts due under the KEESAs.

The KEESAs provide only the Cash Termination Payment and reimbursement of legal and accounting fees in the event of a qualifying termination within 180 days prior to a change in control.

The KEESAs provide that if any portion of the benefits under the KEESAs, or under any other agreement, would constitute an excess parachute payment for purposes of the tax code, the executive may receive the better, on an after-tax basis, of either a payment $1 less than the maximum amount they may receive without becoming subject to the 20% excise tax, or receive the fully calculated payment subject to applicable excise taxes for which they would be personally responsible. The potential payment and benefit amounts shown in the table above assume the executives receive the full payment under the KEESAs without giving effect to the cutback provision.

In consideration of the KEESA benefits, the executive agrees not to compete with us for a period of one year after the executive leaves us, and to keep in confidence any proprietary information or confidential information for a period of five years after the executive officer leaves us. Both of these conditions can be waived in writing by our CEO and Board of Directors, respectively.

Under the KEESAs, a “change in control” is deemed to have occurred if:

•any person (with certain exceptions set forth in the KEESAs) is or becomes the beneficial owner of securities representing 30% or more of our outstanding shares of common stock or combined voting power

•there is a change in a majority of our Board of Directors during a 12-month period that is not approved by at least two-thirds of the existing directors

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EXECUTIVE COMPENSATION

•we complete a merger, consolidation or share exchange with any other corporation (or the issuance of voting securities in connection with a merger, consolidation or share exchange) in which our shareowners control less than 50% of the combined voting power after the merger, consolidation or share exchange, or

•our shareowners approve, and we complete, a plan of complete liquidation or dissolution or we effect the sale or disposition of all or substantially all of our assets.

Under the KEESAs, the term “cause” generally means:

•engaging in intentional conduct that causes us demonstrable and serious financial injury

•conviction of a felony that substantially impairs the officer’s ability to perform duties or responsibilities, or

•continuing willful and unreasonable refusal by an officer to perform duties or responsibilities.

Under the KEESAs, the term “good reason” generally means:

•a material breach of the agreement by us

•a material diminution in the officer’s base compensation, or

•a material diminution in the officer’s authority, duties or responsibilities, including a material diminution in the budget over which he or she retains authority.

The executive must notify the Company of the existence of the good reason event within 90 days of such event, and the Company must be given a 30-day period to cure the event.

Long-Term Equity Award Agreements

The agreements under which we have awarded long-term equity grants to our executive officers prior to December 31, 2023 provide that:

•if the performance contingency under the award is satisfied and if the executive’s employment is terminated by reason of death, disability, or retirement after the end of the first performance year of the performance period, the executive will be entitled to the full value of the award earned at the end of the performance period

•if the performance contingency under the award is satisfied and if the executive’s employment is terminated by reason of death, disability, or retirement during the first year of the performance period, the executive will be entitled to a prorated value of the award, determined at the end of the performance period, based on the ratio of the number of months the executive was employed during the performance period to 12 months

•if the performance contingency under the award is satisfied and if the executive’s employment is terminated by reason of involuntary termination without cause, the executive will be entitled to the prorated value of the award, determined at the end of the performance period, based on the ratio of: (i) the number of months the executive was employed during the performance period to (ii) the total number of months in the performance period

•with respect to restricted stock units that vest based on continuous service: (i) if the executive’s employment is terminated by reason of death, disability, or retirement on or after the first anniversary of the vesting period’s start date, the executive will be entitled to the full value of the award, and if such termination is prior to the first anniversary of the vesting period’s start date, the executive will be entitled to a prorated value of the award, based on the ratio of the number of months the executive was employed during the period to 12 months, and (ii) if the executive’s employment is terminated by reason of involuntary termination without cause after the first anniversary of the grant date, the executive will be entitled to a prorated value of the award, based on the ratio of the number of months the executive was employed following the vesting period start date to 36 months, in each case payable at the end of the vesting period, and

•if a change in control of our Company occurs, which is generally defined in the same manner as under the KEESAs, the executive will be entitled to receive, in a single lump sum following the end of the performance period, and subject to continuous employment (with exceptions for certain qualifying terminations), the cash value of the long-term equity awards as follows: (i) in the case of performance shares and performance restricted stock units, at the value based on the Company’s stock price as of the date immediately preceding the change in control date multiplied by the number of target performance shares or performance restricted stock units, and (ii) in the case of restricted stock units, the value of the full number of restricted stock units based on the stock price as of the date immediately preceding the change in control date (including, in each case, any accrued unearned dividend equivalents).

Retirement means the officer has reached age 55 and the officer’s age, in whole years, added to the number of whole years of the officer’s continuous employment with the Company, totals 65 or greater.

The tables above include the amounts attributable to the shares that would be received by our named executive officers valued at the closing price of our common stock on December 29, 2023 and assuming, in the case of a termination by reason of death, disability, involuntary termination without cause, or retirement, that any applicable performance contingency was satisfied at target.

Executive Severance Plan

We also maintain a general executive severance plan, which applies if an executive’s position is eliminated or significantly altered by us. The plan provides for a minimum level of severance pay equal to: (i) lump sum payment of one times the executive’s annual base salary, (ii) up to 18 months of COBRA coverage, or to the extent eligible, retiree medical coverage (six months of either are paid by us), (iii) outplacement services and/or tuition reimbursement of up to $10,000, and (iv) access to our employee assistance program.

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EXECUTIVE COMPENSATION

Eligibility for benefits under this plan is conditioned on the executive executing a severance agreement and release form. Severance packages of executive officers are approved by the Compensation and Personnel Committee.

Pension Plans

The tables above do not include any amounts for the Alliant Energy Cash Balance Pension Plan because the plan is not impacted by the nature of the termination of employment nor whether there has been a change in control of the Company. The tables above also do not include any amounts for the DB SRP other than in the event of a termination after a change in control because those plans are not impacted by the nature of the termination of employment unless there has been a change in control of our Company, in which case the benefits under the DB SRP may be enhanced under the KEESAs as described above under Change in Control Agreements. The tables above show an amount for Ms. Barton related to the Alliant Energy Excess Retirement Plan in the event of a change in control because her unvested balance would be fully vested under the KEESA. All other named executive officers are fully vested in the Excess Retirement Plan, except Mr. Sundararajan whose unvested balance was de minimis.

ALLIANT ENERGY | 2024 Proxy Statement | 57

EXECUTIVE COMPENSATION

PAY VERSUS PERFORMANCE

We believe our compensation philosophy and approach creates a strong link between executive compensation and Company performance. As described more fully in our Compensation Discussion and Analysis, our executive compensation program is guided by our purpose and values and is designed to promote our strategy.

In accordance with SEC rules, the table below shows (i) the compensation reported in the Summary Compensation Table and the Compensation Actually Paid (calculated in accordance with SEC rules) for the Principal Executive Officer (PEO) for each year below and (ii) the average compensation reported in the Summary Compensation table for the non-PEO Named Executive Officers and the average Compensation Actually Paid (calculated in accordance with SEC rules) for the non-PEO Named Executive Officers for each year below. It also includes the total shareholder return (TSR) for Alliant Energy and our defined peer group, our net income and adjusted EPS for each year. References to the Company in this section refer to Alliant Energy.

					Value of initial fixed $100 investment based on:
Year	Summary Compensation Table Total for PEO(1)	Compensation Actually Paid to PEO(3)	Average Summary Compensation Table Total for non-PEO Named Executive Officers(2)	Average Compensation Actually Paid to non-PEO Named Executive Officers(3)	Alliant Total Shareholder Return(4)	Peer Group Total Shareholder Return(4)	Alliant Net Income (5) (Millions)	Alliant Adjusted EPS (6)
2023	$9,709,782	$7,235,148	$2,593,105	$2,483,122	$106.09	$106.90	$703	$2.82
2022	$7,286,977	$5,361,068	$1,558,260	$1,132,675	$110.24	$117.09	$686	$2.80
2021	$10,449,260	$10,185,275	$1,630,049	$2,208,076	$119.13	$115.76	$674	$2.65
2020	$11,020,134	$5,985,432	$1,639,294	$1,643,446	$97.08	$98.84	$624	$2.44

(1) Reflects Summary Compensation Table Total compensation for Mr. Larsen, our PEO, as reported in the 2023, 2022, 2021 and 2020 proxy statements.

(2) Reflects Summary Compensation Table Total compensation for the following non-PEO Named Executive Officers (NEOs) reported in the proxy statements in each of the listed years:

Name	2023	2022	2021	2020
Lisa M. Barton	X	N/A	N/A	N/A
Robert J. Durian	X	X	X	X
Raja Sundararajan	X	N/A	N/A	N/A
David A. de Leon	X	X	X	X
Terry L. Kouba	X	X	X	X
James H. Gallegos	N/A	X	X	X
Michael S. Luhrs	N/A	X	N/A	N/A

ALLIANT ENERGY | 2024 Proxy Statement | 58

EXECUTIVE COMPENSATION

(3) The following adjustments were made to Total compensation reported in the Summary Compensation Table (SCT) for each year below to arrive at compensation actually paid to the PEO and the non-PEO NEOs, computed in accordance SEC rules. Amounts below are based on average amounts for the non-PEO NEOs in the year indicated below.

	2023
	PEO ($)	Average non-PEO NEOs ($)
SCT Total	$9,709,782	$2,593,105
Less SCT Grant Date Fair Value of Equity Awards	($5,191,716)	($1,208,708)
Less SCT Change in Pension Value	($1,354,440)	($11,739)
Plus Pension Plan Service Cost During Applicable Year	$35,430	$3,629
+/- Change in Fair Value as of Year-End for Equity Awards Granted in Prior Fiscal Years that Remain Outstanding and Unvested at Year-End	($954,751)	($90,887)
+/- Change in Fair Value as of Vest Date for Equity Awards Granted in Any Prior Year That Vest During Applicable Year (Compared to Fair Value as of Prior Year-End)	($196,448)	($18,843)
+ Fair Value as of Year-End for Equity Awards Granted and that Remain Outstanding and Unvested at Year-End	$5,187,291	$1,216,565
Compensation Actually Paid	$7,235,148	$2,483,122

(4) Reflects the Company’s TSR and Peer Group TSR based on the EEI Stock Index. The EEI Stock Index is used to evaluate the Company’s TSR against peers as disclosed in the Compensation Discussion and Analysis and is also set forth in the stock performance graph included in the Company’s annual report for the year ended December 31, 2023. The amounts reported assume $100 was invested, as applicable, in each of the Company and the EEI Stock Index for the period starting December 31, 2019 through the end of the listed year.

(5) The Company’s Net Income as reported in its GAAP audited financial statements for the listed year.

(6) The Company’s Adjusted EPS as reported for the listed year in its proxy statements. Adjustments to GAAP EPS for 2021, 2022 and 2023 are shown on page 24 in the Compensation Discussion and Analysis. Adjusted EPS in 2020 excludes a gain of $0.02 per share related to credit loss adjustments on a guarantee for an affiliate of Whiting Petroleum Corporation, a gain of $0.02 per share related to a tax valuation allowance adjustment, and a loss of $0.01 per share resulting from a settlement loss for the IPL retirement plan.

Most Important Financial Metrics

The most important financial performance metrics used by the Compensation and Personnel Committee for linking compensation actually paid to our PEO and our other NEOs to Company performance for 2023 are set forth below.

Financial Metric

Total Shareholder Return (TSR)

Net Income

Earnings Per Share (EPS)

ALLIANT ENERGY | 2024 Proxy Statement | 59

EXECUTIVE COMPENSATION

Relationship Between Compensation Actually Paid and Financial Performance Measure

Our compensation programs are designed to link executive pay to the financial performance of the Company. As shown below, our executive compensation has a strong link to TSR, Net Income and EPS performance. This strong link is created by our long-term incentive compensation being heavily weighted to TSR and Net Income and our annual incentive compensation being heavily weighted to EPS. Our incentive compensation plan design is discussed further in the Compensation Discussion and Analysis. The following graphs further illustrate the relationship between the pay and performance figures that are included in the pay versus performance tabular disclosure above.

ALLIANT ENERGY | 2024 Proxy Statement | 60

ADVISORY VOTE TO APPROVE THE COMPENSATION OF OUR NAMED EXECUTIVE OFFICERS

Proposal Two—ADVISORY VOTE TO APPROVE THE COMPENSATION OF

OUR NAMED EXECUTIVE OFFICERS 

Pursuant to Section 14A of the Securities Exchange Act of 1934, we ask shareowners to cast an advisory, non-binding vote to approve the compensation of our named executive officers as disclosed in the Compensation Discussion and Analysis and the accompanying compensation tables and narrative discussions contained in this Proxy Statement. While this vote is non-binding, we value the opinions of our shareowners and will consider the outcome of the vote when making future compensation decisions. The Board of Directors has adopted a policy to hold this advisory vote on the compensation of our named executive officers annually, with the next vote on the compensation of our named executive officers expected to occur at our 2025 Annual Meeting of Shareowners.

In considering your vote, we invite you to review the Compensation Discussion and Analysis beginning on page 22 of this Proxy Statement. As described in the Compensation Discussion and Analysis, we believe that our compensation programs effectively meet our objectives of rewarding strong performance, aligning the interests of executives and shareowners and maintaining our competitive positioning for top talent critical to our success.

Accordingly, the Board of Directors recommends that the shareowners vote, on an advisory, non-binding basis, in favor of the following resolution:

“RESOLVED, that the shareowners approve, on an advisory basis, the compensation of the named executive officers as disclosed pursuant to Item 402 of Regulation S-K, including the Compensation Discussion and Analysis and the compensation tables and related narrative discussion contained in this Proxy Statement.”

The votes cast FOR must exceed the votes cast AGAINST the proposal at the Annual Meeting (assuming a quorum is present) to approve the compensation of our named executive officers as disclosed in this Proxy Statement. For purposes of determining the vote required for this proposal, abstentions and broker non-votes will have no impact on the vote. This advisory vote on the compensation of our named executive officers is not binding on us, our Board of Directors or the Compensation and Personnel Committee. However, our Board of Directors and the Compensation and Personnel Committee will review and consider the outcome of this advisory vote when making future compensation decisions for our named executive officers.

þ The Board of Directors recommends a vote FOR approval, on an advisory, non-binding basis, of the compensation of our named executive officers as disclosed in this Proxy Statement.

ALLIANT ENERGY | 2024 Proxy Statement | 61

REPORT OF THE AUDIT COMMITTEE

REPORT OF THE AUDIT COMMITTEE

The Audit Committee of our Board of Directors at the time this report was approved was composed of three directors, each of whom is independent under the applicable SEC and Nasdaq Stock Exchange rules. The Committee operates under a written charter adopted by the Board of Directors.

Our management is responsible for establishing and maintaining adequate internal control over financial reporting. The independent registered public accounting firm is responsible for expressing opinions that our consolidated financial statements are presented fairly, in all material respects, and are in conformity with accounting principles generally accepted in the United States of America and on the effectiveness of our internal control over financial reporting based on the criteria established by the Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. The Committee has reviewed and discussed the audited consolidated financial statements with management and the independent registered public accounting firm. The Committee discussed with the independent registered public accounting firm matters required to be discussed by Public Company Accounting Oversight Board Auditing Standard No. 1301, SEC regulations (including Rule 2-07 of Regulation S-X) and listing exchange requirements.

Our independent registered public accounting firm has provided to the Committee the written communications required by applicable requirements of the Public Company Accounting Oversight Board regarding the independent registered public accounting firm’s communications with the Committee concerning independence. The Committee has discussed the independence of the independent registered public accounting firm with the firm.

Based on the Committee’s reviews and discussions with management, the internal auditor and the independent registered public accounting firm referred to above, the Committee recommended to the Board of Directors that the audited consolidated financial statements be included in our Annual Report on Form 10-K for the year ended December 31, 2023, for filing with the SEC.

AUDIT COMMITTEE

N. Joy Falotico (Chair)

Roger K. Newport

Carol P. Sanders

ALLIANT ENERGY | 2024 Proxy Statement | 62

AUDIT FEES

FEES PAID TO INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Audit Committee has adopted a policy that requires advance approval of all audit, audit-related, tax and other permitted services performed by the independent registered public accounting firm. The policy provides for pre-approval by the committee of specifically defined audit and non-audit services after the committee is provided with the appropriate level of details regarding the specific services to be provided. The policy does not permit delegation of the committee’s authority to management. In the event the need for specific services arises between committee meetings, the committee has delegated to the Chair of the committee authority to approve permitted services provided that the Chair reports any decisions to the committee at its next scheduled meeting. In accordance with the policy, the committee pre-approved all audit, audit-related, tax and other permitted services performed by Deloitte & Touche LLP and its affiliates and related entities in 2023.

The fees that were billed to the Company by its independent registered public accounting firm for work performed on behalf of our Company and our subsidiaries for 2022 and 2023 were as follows:

Component	2022	2023
Audit Fees	$2,742,000	$3,149,000
Audit-Related Fees	$156,000	$167,000
Tax Fees	$33,000	$394,000
All Other Fees	$13,000	$8,000

Audit fees consisted of the fees billed for: (i) the audits of the consolidated financial statements of our Company and our subsidiaries included in our Form 10-K; (ii) the audit of the effectiveness of our internal controls over financial reporting; (iii) reviews of financial statements included in Form 10-Q filings; and (iv) services normally provided in connection with statutory and regulatory filings, such as financing transactions.

Audit-related fees consisted of the fees billed for services rendered related to employee benefits plan audits and other attest services.

Tax fees consisted of the fees billed for professional services rendered for tax compliance, tax advice and tax planning, including all services performed by the tax professional staff of affiliates of the independent registered public accounting firm, except those rendered in connection with the audit.

All other fees for 2022 and 2023 consisted of license fees for accounting research software products and seminars.

The Audit Committee does not consider the provision of non-audit services by the independent registered public accounting firm described above to be incompatible with maintaining the independence of the independent registered public accounting firm. The committee discussed with our internal auditor and independent registered public accounting firm the overall scope and plans for their respective audits. The committee meets with the internal auditor and independent registered public accounting firm, with and without management present, to discuss the results of their examinations, the evaluation of our internal controls and the overall quality of our financial reporting.

ALLIANT ENERGY | 2024 Proxy Statement | 63

RATIFICATION OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Proposal Three—RATIFICATION OF THE APPOINTMENT OF DELOITTE & TOUCHE LLP AS THE COMPANY’S INDEPENDENT REGISTERED PUBLIC ACCOUNTING

FIRM FOR 2024

In accordance with its charter, the Audit Committee of the Board of Directors appointed the firm of Deloitte & Touche LLP, independent registered public accounting firm, to audit the consolidated financial statements of the Company and its subsidiaries for 2024, as well as to report on the effectiveness of our internal controls over financial reporting as of December 31, 2024, and is requesting that its shareowners ratify such appointment.

Representatives of Deloitte & Touche LLP are expected to attend the Annual Meeting where they will be available to respond to appropriate questions and, if they desire, to make a statement. Further information about the services of Deloitte & Touche LLP, including the fees paid in 2022 and 2023, is set forth under Fees Paid to Independent Registered Public Accounting Firm.

The votes cast FOR must exceed the votes cast AGAINST the proposal at the Annual Meeting (assuming a quorum is present) to ratify the appointment of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for 2024. For purposes of determining the vote required for this proposal, abstentions will have no impact on the vote. If the appointment is not ratified, the failure by the shareowners to ratify will be considered by the Audit Committee as an indication that it should consider selecting another independent registered public accounting firm for the following fiscal year. Even if the shareowners ratify the appointment, the Audit Committee, in its discretion, may select a new independent registered public accounting firm at any time during the year if it feels that such a change would be in the best interest of the Company.

þ The Board of Directors recommends a vote FOR the ratification of the appointment of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for 2024.

ALLIANT ENERGY | 2024 Proxy Statement | 64

GENERAL INFORMATION

INFORMATION ABOUT THE ANNUAL MEETING AND VOTING

1.    Why am I receiving these materials?

Our Board of Directors is providing these proxy materials to you in connection with our Annual Meeting, which will take place on May 17, 2024. As a shareowner, you are invited to attend the Annual Meeting and are entitled to and requested to vote on the proposals described in this Proxy Statement. In accordance with SEC rules, a notice containing instructions on how to access this Proxy Statement and our annual report online was mailed, starting on or about April 2, 2024, and we provided access to our materials online before that date to holders of our common stock on the close of business on the record date.

2.    How can I attend the Annual Meeting?

The 2024 Annual Meeting of Shareowners will be held exclusively online via live webcast. Shareowners of record as of the close of business on March 18, 2024, and persons holding valid proxies from shareowners of record, are entitled to participate in and submit questions in writing before and during the Annual Meeting by visiting www.virtualshareholdermeeting.com/LNT2024. To participate in the online Annual Meeting, you will need the 16-digit control number included on your proxy card. If you hold your shares through a broker, bank or other record holder, you may gain access to the meeting by logging into your brokerage firm’s website and selecting the stockholder communications mailbox to link through to the Annual Meeting. Instructions should also be provided on the voting instruction card provided by your broker, bank or other record holder.

The Annual Meeting will begin promptly at 9:00 a.m. CDT. Online check-in will begin at 8:45 a.m. CDT. Please allow ample time for the online check-in procedures.

An audio broadcast of the Annual Meeting will be available by telephone toll-free at (877) 346-6110. If you call the toll-free number, you will be able to listen to the Annual Meeting but will not be able to vote your shares or ask questions.

3.    How can I ask questions at the Annual Meeting?

If you wish to submit a question prior to the Annual Meeting, you may do so prior to the meeting by logging into www.proxyvote.com and entering your 16-digit control number. Once past the log-in screen, click on Question for Management, type in your question, and click Submit. Alternatively, if you want to submit your question during the meeting, log into the virtual meeting platform at www.virtualshareholdermeeting.com/LNT2024, type your question into the Ask a Question field, and click Submit.

Questions pertinent to meeting matters will be answered during the meeting, subject to time constraints. Questions relating to employee or retiree benefits, which further personal interests that may not be of interest to all shareowners or are rude or derogatory are not pertinent to meeting matters and therefore will not be answered. Any questions pertinent to meeting matters that cannot be answered during the meeting due to time constraints will be answered online and posted at the Investors tab of our website at www.alliantenergy.com/investors.

4.    Why are you holding the Annual Meeting online?

This is our seventh year holding a virtual-only Annual Meeting. We believe that a virtual Annual Meeting facilitates greater participation by providing easy access to the meeting and allowing shareowners to participate from any location around the world. All of our shareowners will be able to participate in the Annual Meeting online without prohibitive cost or inconvenience and without other logistical issues connected with a physical meeting. All shareowners can submit questions in writing as provided in Question 3. A replay of the meeting will be available for one year at that website and on the Investors tab of our website at www.alliantenergy.com/investors.

5.    What if I have difficulties accessing the pre-meeting forum or locating my 16-digit control number prior to the day of the Annual Meeting?

Prior to the day of the Annual Meeting, if you need assistance with your 16-digit control number and you hold your shares in your own name, please call toll-free (800) 353-1089 in the United States. If you hold your shares in the name of a bank or brokerage firm, you will need to contact your bank or brokerage firm for assistance with your 16-digit control number.

6.    What if I have technical difficulties or trouble accessing the webcast of the Annual Meeting?

If you encounter any difficulties accessing the webcast of the Annual Meeting during the check-in or during the Annual Meeting itself, including any difficulties with your 16-digit control number, please call toll-free (844) 976-0738 in the United States, or (303) 562-9301 if calling from outside the United States, for assistance. Technicians will be ready to assist you beginning at 8:45 a.m. CDT.

7.    Who is entitled to vote at the Annual Meeting?

Only shareowners of record at the close of business on March 18, 2024 are entitled to vote at the Annual Meeting. As of the record date, 256,378,014 shares of our common stock were issued and outstanding. Each shareowner is entitled to one vote for each share of our common stock held on the record date.

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8.    What items will be voted on in the Annual Meeting?

You may vote on the following proposals:

•Elect six directors nominated by our Board of Directors to serve on our Board of Directors, one for a term expiring at the 2025 Annual Meeting of Shareowners, one for a term expiring at the 2026 Annual Meeting of Shareowners and four for terms expiring at the 2027 Annual Meeting of Shareowners

•Approve, on an advisory, non-binding basis, the compensation of our named executive officers

•Ratify the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for 2024

9.    How does the Board of Directors recommend I vote?

The Board of Directors recommends you vote:

•FOR each of the listed director nominees

•FOR approval of the compensation of our named executive officers

•FOR the ratification of the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for 2024

10.    How do I vote?

You may vote your shares by proxy or online during the Annual Meeting. Your Board of Directors recommends you vote by proxy even if you plan to participate in the Annual Meeting. You may vote in one of four ways:

Online Prior to the Annual Meeting: You may vote by proxy online. Go to www.proxyvote.com and follow the instructions found on your proxy card.

Online During the Annual Meeting: You may vote online during the Annual Meeting by visiting www.virtualshareholdermeeting.com/LNT2024 and following the instructions found on your proxy card.

By Telephone: You may vote by proxy by calling the toll-free number found on the proxy card.

By Mail: You may vote by proxy by filling out the proxy card and mailing it back in the envelope provided.

If you return your signed proxy card but do not mark the boxes to indicate how you wish to vote on one or more of the proposals, your shares will be voted FOR each of the listed director nominees; FOR approval of the compensation of our named executive officers; and FOR the ratification of the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for 2024. If your proxy card is not signed, your votes will not be counted.

If your shares are held by a broker, bank or other record holder, you may direct the record holder to vote your proxy as provided on the notice received from the record holder. If you do not provide your broker, bank or other record holder with specific and timely voting instructions, your shares will not be voted except on Proposal Three — Ratification of the Appointment of Deloitte & Touche LLP as our Independent Registered Public Accounting Firm for 2024.

Alliant Energy is incorporated under Wisconsin law, which specifically permits electronically transmitted proxies, provided that it can be determined that the transmission was sent or authorized by the shareowner. The electronic voting procedures are designed to authenticate each shareowner by use of a control number and to confirm that the shareowner instructions are properly recorded.

11.    Can I change my vote?

Yes, you have the right to revoke your proxy at any time before the Annual Meeting by: (a) providing written notice to our Corporate Secretary at 4902 North Biltmore Lane, Madison, Wisconsin 53718; or (b) appointing a new proxy prior to the start of the Annual Meeting.

Additionally, if you attend the Annual Meeting virtually and wish to vote online during the Annual Meeting, you may revoke your proxy by voting online at that time as described above. Attendance at the Annual Meeting will not, by itself, cause your previously appointed proxy to be revoked.

If your shares are held by a bank, broker or other record holder on your behalf, you may submit voting instructions in accordance with the process provided by such record holder.

12.    What shares are included on the proxy card(s)?

Your proxy card(s) covers all of your shares of our common stock, including any shares held in your account under our Shareowner Direct Plan and the Alliant Energy Corporation 401(k) Savings Plan.

13.    How are shares voted that are held for employees in the Alliant Energy Corporation 401(k) Savings Plan?

Shares held in the Alliant Energy Corporation 401(k) Savings Plan will be included on the proxy card that covers all of your shares of our common stock and can be voted as described in Question 10. You will not receive a separate proxy card for these shares.

14.    How does the proxy voting process work?

Only if the proxy is voted as described above in Question 10 will the proxy be voted in accordance with your instructions. If a proxy is given, the persons named in the proxy will have authority to vote in accordance with their best judgment on any other matter that is properly presented for action at the meeting.

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15.    What is the required vote for each proposal, assuming a quorum has been met?

A quorum is met if at least a majority of the shares of our common stock entitled to vote is represented in person or by proxy at the Annual Meeting. Abstentions and broker non-votes count as present for establishing a quorum. If you have returned valid proxy instructions or vote during the meeting, your shares will be counted for the purpose of determining whether there is a quorum, even if you abstain from any matter introduced at the Annual Meeting.

Assuming a quorum is present at the Annual Meeting, the required vote for each proposal is as follows:

•    Election of Directors — Directors will be elected by a majority of the votes cast at the Annual Meeting. See Question 20 “What happens if a director nominee does not receive a majority of votes cast?” for information concerning our director resignation policy. A majority of votes cast means that the votes cast FOR a director’s election exceeds the number of votes cast AGAINST that director’s election. Abstentions and broker non-votes will not be counted as votes cast and therefore will have no impact on the vote. The proxies solicited may be voted for a substitute nominee or nominees if any of the nominees are either unable to serve or for good reason will not serve — a contingency the Board of Directors does not currently anticipate.

•    Advisory Vote on Compensation of Our Named Executive Officers — Approval of the advisory vote on executive compensation requires that the votes cast FOR the proposal exceed the votes cast AGAINST the proposal at the Annual Meeting. Abstentions and broker non-votes will have no impact on the vote.

•    Ratification of Appointment of Independent Registered Public Accounting Firm — Approval of the ratification of the appointment of our independent registered public accounting firm requires that the votes cast FOR the proposal exceed the votes cast AGAINST the proposal at the Annual Meeting. Abstentions will have no impact on the vote, and there will be no broker non-votes with respect to the proposal because brokers may exercise their discretion to vote for or against the proposal in the absence of instruction from the beneficial owners.

16.    Is there any other business to be conducted?

Our Board of Directors does not know of any business to be considered at the Annual Meeting other than the three proposals set forth in this Proxy Statement and listed in Question 8 above.

17.    Who tabulates the votes?

The inspector of election appointed for the Annual Meeting will separately tabulate affirmative and negative votes, abstentions and broker non-votes.

18.    Is there a list of shareowners entitled to vote at the Annual Meeting?

A list of the names of shareowners of record entitled to vote at the Annual Meeting will be available during the entire time of the Annual Meeting on the virtual annual meeting website. This list will also be available for inspection at our Madison, Wisconsin, headquarters. If you would like to view this shareowner list, please contact us in writing.

19.    Where and when will I be able to find the results of the voting?

The preliminary results of the voting will be announced during the Annual Meeting, or you may call us for the results at (800) 353-1089. We will also file the final voting results on a Current Report on Form 8-K with the SEC within four business days following the Annual Meeting.

20.    What happens if a director nominee does not receive a majority of votes cast?

Pursuant to our Bylaws, if any nominee for director in an uncontested election (i.e., an election where the number of nominees is not greater than the number of directors to be elected) receives more AGAINST votes than FOR votes, the director nominee is required to offer his or her resignation to the Chair of the Board of Directors following certification of the shareowner vote. The Nominating and Governance Committee will consider such resignation and make a recommendation to the Board as to whether to accept or reject the tendered resignation, or whether other action should be taken. The Board will act on the tendered resignation, taking into account the Nominating and Governance Committee’s recommendation and all other factors deemed relevant, and publicly disclose (by a press release, a filing with the SEC or other broadly disseminated means of communication) its decision regarding the tendered resignation within 90 days from the date of final certification of the shareowner vote. The director who has tendered a resignation pursuant to this provision will not participate in the Nominating and Governance Committee’s or the Board’s deliberations or decision with respect to the tendered resignation. Full details of our majority voting policy are set forth in our Bylaws and on our website at www.alliantenergy.com/investors under the Corporate Governance link.

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21.    What does it mean if I get more than one proxy card?

If your shares are registered differently and are in more than one account, then you will receive more than one proxy card. Be sure to vote all of your accounts to ensure that all of your shares are voted. When possible, we encourage you to have all accounts registered in the same name and address. You can do this by contacting EQ Shareowner Services at the address below:

EQ Shareowner Services

1110 Centre Pointe Curve, Suite 101

Mendota Heights, MN 55120

or

P. O. Box 64854

St. Paul, MN 55164-0854

(800) 356-5343

www.shareowneronline.com

22.    Are the 2023 Annual Report and these proxy materials available online?

Yes. As required by the SEC, our Proxy Statement and Annual Report are available to our shareowners electronically via the internet. You can access these materials at www.alliantenergy.com/eproxy.

23.    How can I access future proxy materials and Annual Reports online?

If you are a shareowner of record, you can consent to access our future notices of shareowner meetings, proxy materials and Annual Reports electronically through our website.

Selecting electronic access allows us to save on the cost of producing and mailing these materials. If shareowners want to consent to electronic access, they should simply mark the appropriate box on a proxy card or follow the instructions provided when voting online or by telephone. If you consent to access these materials online, you will receive a proxy card in the mail next year with instructions containing the internet address to access those materials rather than receiving those proxy materials and the Annual Report by mail. Your consent will remain in effect unless it is revoked by writing to EQ Shareowner Services at the shareowner information address shown in Question 21 above.

If you consent to electronic access, then you will be responsible for your routine charges (e.g., online fees) in connection with electronic viewing and printing of proxy materials and Annual Reports. We will continue to distribute printed materials to shareowners who do not consent to access these materials electronically.

If your shares are held by a bank, broker or other record holder on your behalf, please refer to the information provided by such record holder for instructions on how to elect to view future proxy materials and Annual Reports over the Internet.

24.    Why did I receive a one-page notice in the mail regarding the internet availability of proxy materials instead of a full set of proxy materials?

Pursuant to rules adopted by the SEC, we have elected to provide access to our proxy materials online. Accordingly, certain shareowners of record received a notice of internet availability of proxy materials. All such shareowners have the ability to access the proxy materials online on the website referred to in the notice, as described in the instructions on the notice. If you prefer to receive your proxy materials in printed form by mail or electronically by email on an ongoing basis, follow the instructions on the notice to make your request. We encourage shareowners to take advantage of the availability to access the proxy materials online to help reduce the cost and environmental impact of the circulation of proxy materials.

25.    When are shareowner proposals for the 2025 Annual Meeting due?

Pursuant to Rule 14a-8 under the Securities Exchange Act of 1934 (Rule 14a-8), all shareowner proposals to be considered for inclusion in our Proxy Statement for the 2025 Annual Meeting must be received at our principal office by December 3, 2024.

In addition, any shareowner who intends to present a proposal, including director nominations, at the 2025 Annual Meeting must comply with the requirements set forth in our Bylaws. Our Bylaws state, among other things, that to bring business before an Annual Meeting, a shareowner must give written notice that complies with the Bylaws to our Corporate Secretary not earlier than the close of business on the 120th day and not later than the close of business on the 90th day prior to the first anniversary of the preceding year’s annual meeting. Accordingly, we must receive notice of a shareowner’s proposal submitted other than pursuant to Rule 14a-8, including director nominations, after January 17, 2025 and no later than February 16, 2025. If the notice is received after February 16, 2025, then the notice will be considered untimely, and we are not required to present such proposal or director nomination at the 2025 Annual Meeting. The persons named in the proxies solicited by the Board of Directors for the 2025 Annual Meeting will use their discretion to vote proxies in certain cases if the shareowner does not comply with this deadline and in certain other cases notwithstanding the shareowner’s compliance with these deadlines. In addition to satisfying the requirements of our Bylaws, including the notice deadlines set forth above and therein, to comply with the universal proxy rules, shareowners who intend to solicit proxies in support of director nominees other than the Company’s nominees must also provide notice that sets forth the information required by Rule 14a-19 of the Securities Exchange Act of 1934, as amended.

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26.    Who is our independent registered public accounting firm and how is it appointed?

Deloitte & Touche LLP audited our financial statements for 2023. Representatives of Deloitte & Touche LLP are expected to be present at the Annual Meeting. They will be given the opportunity to make a statement and to be available to respond to appropriate questions. The Audit Committee of the Board of Directors has appointed Deloitte & Touche LLP as our independent registered public accounting firm for 2024 and is recommending the appointment for ratification by shareowners.

27.    Who will bear the cost of soliciting proxies for the Annual Meeting and how will these proxies be solicited?

We will pay the cost of preparing, assembling, printing, mailing and distributing these proxy materials. In addition to the mailing of these proxy materials, the solicitation of proxies or votes may be made in person, by telephone or by electronic communication by our officers and employees, who will not receive any additional compensation for these solicitation activities. We will pay banks, brokers, nominees and other fiduciaries reasonable charges and expenses incurred in forwarding the proxy materials to their principals. We have retained Innisfree to aid in the solicitation of proxies at an estimated cost of $17,000, plus reimbursable out-of-pocket expenses.

28.    If more than one shareowner lives in my household, how can I obtain an extra copy of the Proxy Statement and the 2023 Annual Report?

Pursuant to SEC rules, services that deliver our communications to shareowners who hold their shares through a bank, broker or other holder of record may deliver to multiple shareowners sharing the same address a single copy of our Annual Report and Proxy Statement. Upon written or oral request, we will mail an additional copy of the Proxy Statement and the 2023 Annual Report to any shareowner at a shared address to which a single copy of the document was previously delivered, and we will continue to do so in the future, if requested. You may call us at (800) 353-1089 or write to the address below to request a copy of our 2023 Annual Report on Form 10-K. You may also access these materials at www.alliantenergy.com/eproxy. In addition, shareowners who receive multiple copies of our Annual Report and Proxy Statement may request delivery of single copies by contacting us in the manner provided above.

We will furnish to any shareowner, without charge, a copy of our 2023 Annual Report on Form 10-K. To request a copy, write to Alliant Energy Shareowner Services at 4902 North Biltmore Lane, P.O. Box 14720, Madison, Wisconsin 53708-0720 or via email at shareownerservices@alliantenergy.com.

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