UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

SCHEDULE 14A INFORMATION

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Securities Exchange Act of 1934

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☐ Definitive Proxy Statement

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CHINOOK THERAPEUTICS, INC.

(Name of Registrant as Specified In Its Charter)

N/A

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Your Vote Counts! CHINOOK THERAPEUTICS, INC. 2022 Annual Meeting Vote by May 25, 2022 11:59 PM ET CHINOOK THERAPEUTICS, INC. 400 FAIRVIEW AVE. NORTH 9TH FLOOR SEATTLE, WA 98109 You invested in CHINOOK THERAPEUTICS, INC. and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy material for the shareholder meeting to be held on May 26, 2022. Get informed before you vote View the Notice & Proxy Statement, Annual Report online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 12, 2022. If you would like to request a copy of the material(s) for this and/or future shareholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy. For complete information and to vote, visit www.ProxyVote.com Control # Smartphone users Point your camera here and vote without entering a control number R Vote Virtually at the Meeting* May 26, 2022 8:00 AM PDT Virtually at: www.virtualshareholdermeeting.com/KDNY2022 *Please check the meeting materials for any special requirements for meeting attendance.

Vote at www.ProxyVote.com THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming shareholder meeting. Please follow the instructions on the reverse side to vote these important matters. Voting Items 1. Election of Directors Nominees: 01) Jerel Davis, Ph.D. 2) William M. Greenman 2. Ratify the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2022. 3. Advisory vote on the compensation of the Company’s named executive officers. NOTE: Such other business as may properly come before the meeting or any adjournment thereof. Board Recommends For Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Sign up for E-delivery”.