POWERING GROWTH DELIVERING VALUE First Quarter 2022 Results May 4, 2022 1

Forward Looking Statements 2 This presentation contains forward-looking statements based on current expectations, including statements regarding our earnings guidance and financial outlook and goals. These forward-looking statements are often identified by words such as “estimate,” “predict,” “may,” “believe,” “plan,” “expect,” “require,” “intend,” “assume,” “project,” "anticipate," "goal," "seek," "strategy," "likely," "should," "will," "could," and similar words. Because actual results may differ materially from expectations, we caution you not to place undue reliance on these statements. A number of factors could cause future results to differ materially from historical results, or from outcomes currently expected or sought by Pinnacle West or APS. These factors include, but are not limited to: the potential effects of the continued COVID-19 pandemic, including, but not limited to, demand for energy, economic growth, our employees and contractors, vaccine mandates, supply chain, expenses, inflation, capital markets, capital projects, operations and maintenance activities, uncollectable accounts, liquidity, cash flows, or other unpredictable events; our ability to manage capital expenditures and operations and maintenance costs while maintaining reliability and customer service levels; variations in demand for electricity, including those due to weather, seasonality (including large increases in ambient temperatures), the general economy or social conditions, customer and sales growth (or decline), the effects of energy conservation measures and distributed generation, and technological advancements; the potential effects of climate change on our electric system, including as a result of weather extremes such as prolonged drought and high temperature variations in the area where APS conducts its business; power plant and transmission system performance and outages; competition in retail and wholesale power markets; regulatory and judicial decisions, developments and proceedings; new legislation, ballot initiatives and regulation or interpretations of existing legislation or regulations, including those relating to environmental requirements, regulatory and energy policy, nuclear plant operations and potential deregulation of retail electric markets; fuel and water supply availability; our ability to achieve timely and adequate rate recovery of our costs through our rates and adjustor recovery mechanisms, including returns on and of debt and equity capital investments; our ability to meet renewable energy and energy efficiency mandates and recover related costs; the ability of APS to achieve its clean energy goals (including a goal by 2050 of 100% clean, carbon-free electricity) and, if these goals are achieved, the impact of such achievement on APS, its customers, and its business, financial condition and results of operations; risks inherent in the operation of nuclear facilities, including spent fuel disposal uncertainty; current and future economic conditions in Arizona, including in real estate markets; the direct or indirect effect on our facilities or business from cybersecurity threats or intrusions, data security breaches, war, acts of war, international sanctions, terrorist attack, physical attack, severe storms, or other catastrophic events, such as fires, explosions, pandemic health events, or similar occurrences; the development of new technologies which may affect electric sales or delivery; the cost of debt and equity capital and the ability to access capital markets when required; general economic conditions, including inflation rates, monetary fluctuations and supply chain constraints; environmental, economic and other concerns surrounding coal-fired generation, including regulation of greenhouse gas emissions; volatile fuel and purchased power costs; the investment performance of the assets of our nuclear decommissioning trust, pension, and other postretirement benefit plans and the resulting impact on future funding requirements; the liquidity of wholesale power markets and the use of derivative contracts in our business; potential shortfalls in insurance coverage; new accounting requirements or new interpretations of existing requirements; generation, transmission and distribution facility and system conditions and operating costs; the ability to meet the anticipated future need for additional generation and associated transmission facilities in our region; the willingness or ability of our counterparties, power plant participants and power plant land-owners to meet contractual or other obligations or extend the rights for continued power plant operations; and restrictions on dividends or other provisions in our credit agreements and ACC orders. These and other factors are discussed in Risk Factors described in Part I, Item 1A of the Pinnacle West/APS Annual Report on Form 10-K for the fiscal year ended December 31, 2021 and in Part II, Item 1A of the Pinnacle West/APS Quarterly Report on Form 10-Q for the quarter ended March 31, 2022, which you should review carefully before placing any reliance on our financial statements, disclosures or earnings outlook. Neither Pinnacle West nor APS assumes any obligation to update these statements, even if our internal estimates change, except as required by law. In this presentation, references to net income and earnings per share (EPS) refer to amounts attributable to common shareholders. First Quarter 2022

1st Quarter results negatively impacted by rate case despite higher usage 3 1st Quarter 2022 vs. 1st Quarter 2021 1Q 2021 1Q 2022 $0.32 $0.15 Operating Revenue less Fuel and Purchased Power1 $0.13 O&M1 & 2 $0.08 D&A2 $(0.19) Operating Revenue less Fuel and Purchased Power Federal Tax Reform3 Sales/Usage Transmission Weather Other LFCR GRC Base Rate Impact $ $ $ $ $ $ $ 0.21 0.09 0.08 (0.01) (0.02) (0.07) (0.15) Pension & OPEB Non- service Credits, net $(0.03) Other, net2 $(0.06) 1 Includes costs and offsetting operating revenues associated with renewable energy and demand side management programs, see slide 19 for more information. 2 Includes the impacts from the absence of the Four Corners Selective Catalytic Reduction (SCR) equipment and Ocotillo Modernization Project (OMP) deferrals. 3 TEAM adjuster was transferred into Base Rates upon the conclusion of APS’s most recent rate case. 4 The Q1 2022 effective tax rate is impacted by a change in the timing of recognition for excess deferred taxes related to the 2017 Tax Cuts and Jobs Act. This timing difference is expected to resolve by year end. end First Quarter 2022 Effective Tax Rate4 $(0.10)

Key drivers for EPS guidance1 1 • Retail customer growth 1.5%-2.5% • Weather-normalized retail electricity sales growth of 1.5%-2.5% • Transmission revenues • Operations and maintenance savings • Depreciation and amortization First Quarter 20224 2022 key drivers • 2022 EPS guidance $3.90-$4.10 • Long-term EPS growth target of 5-7%2 • Retail customer growth 1.5%-2.5%3 • Weather-normalized retail electricity sales growth of 3.5-4.5%3 1 As of May 4, 2022. Long-term guidance and key drivers • Property Tax • Interest on new debt • AFUDC • Pension and OPEB 2 Long-term EPS growth rate based on the Company’s current 5-year compound annual growth rate projections from 2022-2026 3 Forecasted guidance range from 2022-2024

$170 $175 $185 $190 $595 $510 $530 $500 $263 $250 $210 $210 $260 $340 $330 $560 $214 $250 $270 $190 2021 2022E 2023E 2024E Other Generation Clean Generation Transmission Distribution Other Total 2022-2024 $4.7B $1.50B $1.53B $1.53B $1.65B 5 Managed capital plan to support customer growth, reliability, and clean transition 2022–2024 as disclosed in the First Quarter 2022 Form 10-Q. First Quarter 2022

Total Approved Rate BaseAPS Rate Base Growth Guidance Year-End Steady rate base growth First Quarter 20226 ACC FERC Rate Effective Date 12/01/2021 6/1/2021 Test Year Ended 06/30/20191 12/31/2020 Rate Base $8.6B $1.8B Equity Layer 54.7% 51.6% Allowed ROE 8.7% 10.75% 1 Adjusted to include post test-year plant in service through 06/30/2020 Rate base $ in billions, rounded $9.1 $11.2 $1.8 $2.4 2020 2021 2022 2023 2024 Projected 5-6% Annual FERC ACC $10.9 $13.6

Our goal is flat total O&M and declining O&M per MWh 7 2021 2022 2023 2024 $29/MWh O&M per MWh Total O&M1 2021: $865M 2022: $820M-$840M 1 Total O&M amounts exclude RES/DSM, and include planned outage amounts of $54M in 2021 and $40M-$50M in 2022. First Quarter 2022

Forecasted sources of capital to fund investments through 2024 No plans to issue equity before end of next rate case 8 Approx. $3 billion Approx. $1 billion $4.7 billion APS Debt2 PNW Debt2 Cash from Operations1 $200-$300 million $400-$500 million 1 Cash from operations is net of shareholder dividends. 2 APS and PNW debt issuance is net of maturities. First Quarter 2022 Total Capital Investment PNW Equity/ Alternatives

Strong balance sheet with attractive long-term debt maturity profile1 9 $M PNW Long-Term DebtAPS Long-Term Debt $0 $200 $400 $600 $800 $1,000 $1,200 2022 2024 2026 2028 2030 2032 2034 2036 2038 2040 2042 2044 2046 2048 2050 As of March 31, 2022 First Quarter 2022 1 Does not include debt at Bright Canyon Energy.

We continue to make progress towards key deliverables First Quarter 202210 ➢ File appeal of last rate case ✓ Filed notice of appeal on December 17 ✓ Filed opening brief on April 27 ➢ Make progress on financing plan ✓ Deferring equity issuance until after next rate case ➢ File new rate case to recover grid investments and reduce regulatory lag ➢ Work with stakeholders on common issues ✓ Received approval of Customer Education and Outreach Plan ➢ Flat total O&M and declining O&M per MWh ➢ Continued progress towards Clean Energy Commitment ➢ Continued support in attracting high tech growth and economic development

APPENDIX

2022 EPS guidance First Quarter 202212 Key Factors and Assumptions as of February 25, 2022 2022 Adjusted gross margin (operating revenues, net of fuel and purchased power expenses, x/RES,DSM,CCT) $2.52 – $2.55 billion • Retail customer growth about 1.5-2.5% • Weather-normalized retail electricity sales volume 1.5-2.5% higher compared to prior year o Includes 0.5-1.5% contribution to sales growth of new large manufacturing facilities and several large data centers • Assumes normal weather for full-year forecast Adjusted operating and maintenance (O&M x/RES,DSM,CCT) $820 – $840 million Other operating expenses (depreciation and amortization, and taxes other than income taxes) $987 – $998 million Other income (pension and other post-retirement non-service credits, other income and other expense) $62 – $66 million Interest expense, net of allowance for borrowed and equity funds used during construction (Total AFUDC ~$64 million) $214 – $232 million Net income attributable to noncontrolling interests $17 million Effective tax rate 13.5% Average diluted common shares outstanding 113.5 million EPS Guidance $3.90 – $4.10

Arizona remains among the fastest growing states in the U.S. 13 Annual Employment Growth Last Three Years1 Steady Housing Growth2 '11 '12 '13 '14 '15 '16 '17 '18 '19 '20 '21 Single Family & Multifamily Housing Permits Maricopa County 8,425 43,378 2 Maricopa County population 4.5M, 62% of state population1 2019-2021 National Arizona (1)% 1% 18% CAGR First Quarter 2022

Best-in-class service territory supports high tech growth and economic development 14 Our Approach: Focus on Four Main Areas Supports Influx of Manufacturing and Data Centers – Examples • Business attraction and expansion • Community development • Entrepreneurial support • Infrastructure support • Taiwan Semiconductor Began building $12B factory • Chang Chun Petrochemical Building 250k sq ft facility • Williams-Sonoma Leased 1.2M sq ft facility • Nestle USA Building 625k sq ft facility • KORE Power Building 1M sq facility • Kohler Co. Building 1M sq ft facility Data centers are projected to create up to 640 MW of capacity needs by 2035 First Quarter 2022

A clear plan for clean energy transition 15 Progress Towards Meeting Clean Energy Commitment1 Pathway 2005 2019 2030 2050 Announced seasonal operations of Four Corners beginning 2023 Contracted for nearly 1600 MW of clean energy and storage to be in service for APS customers by end of 2024 Charted course for healthy mix of APS-owned and third party- owned assets, to be continued through future planned RFPs 24% 50% 65% 100% 1 Since January 2020 First Quarter 2022

Clean Energy Commitment – ~1,600MW in development since 2020 First Quarter 202216 Robust, Diverse Procurement Activity Energy Storage • 201 MW APS-owned resources to retrofit entire fleet of AZ Sun facilities • 300 MW under two long-term PPAs • All resources to be in service between 2022 and 2024 Solar • 150 MW owned by APS and sited near Redhawk generating facility • 160 MW under two long-term PPAs • All resources to be in service in 2023 Solar + Storage • 275 MW under single long-term innovative tolling PPA • Resources to be in service in 2023 and 2024 Wind • 438 MW under two long-term PPAs • Resources to be in service by 2023 Demand Response • 75 MW under 5-year load management agreement; service began in 2021 • APS can call up to 18 load reduction events between June and September annually

2022 Planned Outage schedule First Quarter 202217 Coal, Nuclear and Large Gas Planned Outages Q1 Q2 Q4 Plant Unit Estimated Duration in Days Plant Unit Estimated Duration in Days Plant Unit Estimated Duration in Days N/A N/A N/A Palo Verde 1 30 Palo Verde 3 30

$1 Q1 Q2 Q3 Q4 Gross margin effects of weather First Quarter 202218 Variances vs. Normal$ in millions pretax 2022 $1 Million All periods recalculated to current 10-year rolling average (2011 – 2020). Numbers may not foot due to rounding.

Renewable Energy & Demand Side Management expenses1 First Quarter 202219 $7 $6 $10 $13 $10 $11 $12 $18 $13 $13 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Demand Side Management Renewable Energy 2021 $89 Million 1 Renewable energy and demand side management expenses are offset by adjustment mechanisms. 2022 $23 Million Numbers may not foot due to rounding.

Residential PV applications1 First Quarter 202220 1Monthly data equals applications received minus cancelled applications. As of March 31, 2022 approximately 140,433 residential grid-tied solar photovoltaic (PV) systems have been installed in APS’s service territory, totaling approximately 1,191 MWdc of installed capacity. Excludes APS Solar Partner Program residential PV systems. Note: www.arizonagoessolar.org logs total residential application volume, including cancellations. Solar water heaters can also be found on the site but are not included in the chart above Residential DG (MWdc) Annual Additions 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2019 Applications 2020 Applications 2021 Applications 2022 Applications 122 139 169 52 2019 2020 2021 2022

Our credit ratings support growth opportunities 21 Corporate Ratings Senior Unsecured Ratings Short-Term Ratings Outlook APS1 Moody’s A3 A3 P-2 Negative S&P BBB+ BBB+ A-2 Negative Fitch BBB+ A- F2 Negative Pinnacle West1 Moody’s Baa1 Baa1 P-2 Negative S&P BBB+ BBB A-2 Negative Fitch BBB+ BBB+ F2 Negative Balance Sheet Targets • Strong investment grade credit ratings • APS equity layer >50% • FFO/Debt range of 16%-18% 1 We are disclosing credit ratings to enhance understanding of our sources of liquidity and the effects of our ratings on our costs of funds. Ratings are as of May 4, 2022. First Quarter 2022

Regulatory 2022 key dates First Quarter 202222 ACC Key Dates / Docket # Q1 Q2 Q3 Q4 Power Supply Adjustor (PSA): E-01345A-19-0236 Effective Feb 1 Lost Fixed Cost Recovery: E-01345A-22-0042 Filed Feb 15 Transmission Cost Adjustor: E-01345A-19-0236 To Be Filed: May 15; Effective Jun 1 2022 DSM/EE Implementation Plan: E-01345A-21-0087 2022 RES Implementation Plan: E-01345A-21-0240 2019 Rate Case: E-01345A-19-0236 Petition for Special Action Denied; Court of Appeals in process New TOU Hours to be implemented: Sept 1 Resource Planning and Procurement: E-00000V-19-0034 IRP Acknowledged on February 10 Resource Comparison Proxy (RCP): E-01345A-22-0105 Filed April 29 Rulemaking Requiring All-Source RFPs: RE-00000A-22-0029 Proposed Termination of Service Rule Modifications: RU-00000A-19-0132 Effective Apr 18 Fuel and Purchased Power Audit: E-01345A-21-0056 Staff Report Apr 1

Consolidated statistics1 First Quarter 202223 3 Months Ended June 30 Numbers may not foot due to rounding. 3 Months Ended June 30 2022 2021 Incr (Decr) TOTAL OPERATING REVENUES (Dollars in Millions) Retail Residential 367$ 341$ 27 Business 360 315 45 Total Retail 727 656 71 Sales for Resale (Wholesale) 29 18 11 Transmission for Others 26 19 6 Other Miscellaneous Services 2 4 (2) Total Operating Revenues 784$ 696$ 87 ELECTRIC SALES (GWH) Retail Residential 2,649 2,581 68 Business 3,304 3,143 161 Total Retail 5,954 5,725 229 Sales for Resale (Wholesale) 686 634 52 Total Electric Sales 6,640 6,359 281 3 Months Ended March 31, 2022 2021 Incr (Decr) RETAIL SALES (GWH) - WEATHER NORMALIZED Residential 2,643 2,553 90 Business 3,315 3,154 161 Total Retail Sales 5,958 5,707 251 Retail sales (GWH) (% over prior year) 4.4% 0.2% 4.2% AVERAGE ELECTRIC CUSTOMERS Retail Customers Residential 1,197,775 1,170,332 27,443 Business 140,830 139,500 1,330 Total Retail 1,338,604 1,309,832 28,773 Wholesale Customers 53 40 14 Total Customers 1,338,658 1,309,871 28,786 Total Customer Growth (% over prior year) 2.2% 2.1% 0.1% RETAIL USAGE - WEATHER NORMALIZED (KWh/Average Customer) Residential 2,207 2,182 25 Business 23,537 22,608 929 3 Months Ended March 31, 1 Retail electricity sales in kWh, adjusted to exclude the effects of weather variations, for the year ended December 31, 2021 compared with the prior-year period increased 4.2%, which reflects a correction to 2020 commercial and industrial customer sales volumes of 111 GWh.

Consolidated statistics First Quarter 202224 Numbers may not foot due to rounding. 3 Months Ended June 30 2022 2021 Incr (Decr) WEATHER INDICATORS - RESIDENTIAL Actual Cooling Degree-Days - - - Heating Degree-Days 451 506 (55) Average Humidity 0% 0% 0% 10-Year Averages (2011 - 2020) Cooling Degree-Days - - - Heating Degree-Days 443 443 Average Humidity 0% 0% - 3 Months Ended March 31, 2022 2021 Incr (Decr) ENERGY SOURCES (GWH) Generation Production Nuclear 2,397 2,459 (62) Coal 1,830 1,334 496 Gas, Oil and Other 1,539 1,927 (388) Renewables 116 137 (21) Total Generation Production 5,882 5,857 25 Purchased Power - Conventional 509 364 146 Resales 4 5 (1) Renewables 634 541 93 Total Purchased Power 1,147 909 238 Total Energy Sources 7,030 6,766 263 POWER PLANT PERFORMANCE Capacity Factors - Owned Nuclear 97% 99% (3)% Coal 62% 46% 17% Gas, Oil and Other 20% 25% (5)% Solar 24% 28% (4)% System Average 43% 43% 0% 3 Months Ended March 31,