#1STN TSX NYSE Stantec Q4 and Year End 2023 Earnings Presentation February 29, 2024#22 STN TSX NYSE Q4 AND YEAR END 2023 Y||||||||| 1501406 409 5353 REWATCHAT 412 HITACHI Cautionary statement This presentation contains non-IFRS and other financial measures and forward-looking statements, including a discussion of our business targets, expectations, and outlook. We caution readers not to place undue reliance on our forward-looking statements since a number of factors could cause actual future results to differ materially from the targets and expectations expressed. Non-IFRS and other financial measures do not have a standardized meaning under IFRS, and therefore, may not be comparable to similar measures presented by other issuers. For a discussion of risk factors and non-IFRS measures and other financial measures, see our 2023 Annual Report available on SEDAR+, EDGAR, and stantec.com.#3STN TSX NYSE 2023 Key highlights Record Financial results Highest Organic net revenue growth rate ever achieved Lowest Voluntary turnover among peers 5% Workforce growth through organic hires Corporate Knights Global 100 #1 Ranked the most sustainable design and engineering firm in the world #9 Ranked as one of the most sustainable companies in the world 13#44 Closed two key acquisitions to start 2024 ZETCON Morrison Hershfield 7,60 CAMPS S 645-person engineering firm in all major German metropolitan areas Closed January 8, 2024 1,150-person engineering & management firm with offices in Canada, US, and India Closed February 9, 2024#5LO 5 STN TSX NYSE Record 2023 financial results Net revenue $5.1B | 14% Increased earnings driven by: Q4 AND YEAR END 2023 Adjusted EBITDA (1) Organic Net Revenue Growth (1) $831M ▲ 15% 9.9% Adjusted EBITDA Margin (1) Acquisition Growth (1) 16.4% | 20bps 1.5% Adjusted Diluted EPS (1) Project Margin $3.67 | ▲ 17% 54.2% (1) Adjusted EBITDA, adjusted EBITDA margin, and adjusted diluted EPS are non-IFRS measures, and organic net revenue growth and acquisition growth are other financial measures (discussed in the Definitions section of Stantec's 2023 Annual Report). 2023 KEY DRIVERS Robust investment / demand from both public and private sectors continues Strong project execution Efficiencies gained through operating leverage#66 STN TSX-NYSE Q4 AND YEAR END 2023 United States Gross and net revenue ($ millions) $3,057 $3,635 $2,684 $2,267 $4.0 Billion $822 $902 $578 $662 BACKLOG Q4 2022 Q4 2023 2022 2023 Gross Revenue Net Revenue 5 12.3% organic growth & 2.4% acquisition growth Double-digit organic growth in: • . • - Water public sector and industrial projects; large-scale water security projects in western US Buildings - healthcare, industrial, civic, and science and technology Energy & Resources - hurricane recovery and power grid modernization in Puerto Rico Spaghetti Bowl Express Interchange and Landscape Reno, Nevada, US#77 Q4 AND YEAR END 2023 STN TSX-NYSE Canada Gross and net revenue ($ millions) $1,427 $1,337 $1,246 $1,151 $1.3 Billion $357 $358 $291 $307 BACKLOG Q4 2022 Q4 2023 2022 2023 Gross Revenue Net Revenue 8.3% organic growth Double-digit organic growth in: . • • Environmental Services – permitting, archaeology resource assessments - and environmental impact assessments Infrastructure large-scale bridge and roadway projects Water-wastewater solutions Pelly Cross Pool Calgary, Alberta, Canada#8STN TSX-NYSE Global Q4 AND YEAR END 2023 00 8 Gross and net revenue ($ millions) $1,419 $1,284 $1,136 $1,040 $1.0 Billion $334 $349 $261 $273 BACKLOG Q4 2022 Q4 2023 2022 2023 Gross Revenue Net Revenue 6.5% organic growth & 1.1% acquisition growth Double-digit organic growth in: • • Water - long-term framework agreements in UK, New Zealand and Australia, and public sector investment Energy & Resources - major energy storage project in UK and mining activities. to support the energy transition New City West Bus Layover Turner, ACT, Australia#99 Q 4 AND YEAR END 2023 STN TSX NYSE 2023 ATTENTION AERZEN Jamoned Delta Blower Financial Performance Theresa Jang - Executive Vice President and Chief Financial Officer Hyperion Water Reclamation Plant Los Angeles, California, US#10Q4 AND YEAR END 2023 STN TSX-NYSE Q4 2023 Financial results Gross and net revenue ($ millions) $1,514 $1,609 $1,242 $1,130 Q4 2022 Gross Revenue Q4 2023 Net Revenue Adjusted EBITDA and Adjusted EBITDA margin(1) ($ millions and % of NR) 17.0% 15.7% Project margin ($ millions and % of NR) 54.9% 53.9% $621 $670 Q4 2022 Q4 2023 Adjusted diluted earnings per share ($) (1) $0.82 $0.82 $192 Q4 2022 $195 Q4 2023 Q4 2022 Q4 2023 10 (1) Adjusted EBITDA, adjusted EBITDA margin and adjusted diluted earnings per share are non-IFRS measures (discussed in the Definitions section of Stantec's 2023 Annual Report).#1111 STN TSX-NYSE Q4 AND YEAR END 2023 2023 Financial results Gross and net revenue ($ millions) $5,677 Project margin ($ millions and % of NR) $6,480 54.2% 54.2% $5,066 $4,457 2022 Gross Revenue 2023 Net Revenue Adjusted EBITDA and Adjusted EBITDA margin (1) ($ millions and % of NR) 16.2% 16.4% $831 $724 2022 2023 $2,745 $2,417 2022 2023 Adjusted diluted earnings per share ($) (1) $3.13 2022 (1) Adjusted EBITDA, adjusted EBITDA margin and adjusted diluted earnings per share are non-IFRS measures (discussed in the Definitions section of Stantec's 2023 Annual Report). $3.67 2023#12Q4 AND YEAR END 2023 STN TSX NYSE Liquidity and capital resources Operating cash flow ($ millions) Capital returned to shareholders ($ millions) $210 $545 $304 $264 $65 $10 $78 $85 Q4 2022 Q4 2023 2022 2023 $20 Q4 2022 $22 Q4 2023 2022 2023 Dividends Share Buybacks Dividends Share Buybacks Days sales outstanding(1) 81 Target 80 days 77 2022 2023 Net debt to adjusted EBITDA(1) 1.6 Target range 1.0 - 2.0x 1.0 2022 2023 12 (1) Net debt to adjusted EBITDA and days sales outstanding are non-IFRS measures (discussed in the Definitions section of Stantec's 2023 Annual Report).#1313 Q 4 AND YEAR END 2023 STN TSX NYSE Q4 2023 Backlog, Major Projects & Outlook Gord Johnston - President and Chief Executive Officer East Midtown Greenway New York, New York, US EXCOUNTCLUB#1414 STN TSX NYSE Significant Backlog Backlog ($ millions) Q 4 AND YEAR END 2023 • $6,306 $6,350 $6,306 $5,902 Q4 2022 Q4 2023 Q3 2023 Q4 2023 6.8% growth since December 31, 2022 4.6% organic growth; organic backlog growth in Water and Buildings . Represents approximately 12 months of work. San Fernando Groundwater Basin Remediation Project Los Angeles, California, US#1515 Q 4 AND YEAR END 2023 STN TSX NYSE • Major Project Awards Lithium-ion Battery Cell Manufacturing Facility Hamdan Bin Rashid Cancer Hospital $1 billion project expected to be largest factory in western Canada for high performance lithium-ion battery cells, providing architectural, environmental services and engineering services. • Stantec chosen to provide design services for the Hamdan Bin Rashid Cancer Hospital, Dubai's first integrated, comprehensive cancer hospital, including clinics, clinical trial areas, urgent care, infusion and radiology rooms. living water NORTHUMBRIAN ENTERPHE WATER living water Northumbrian Water's Living Water Enterprise Joint venture partners Esh-Stantec appointed to $3.6 billion AMP8 investment program with a range of engineering, design, and build services. . SEVERN TRENT Severn Trent Water WATER Appointed to the AMP8 design services framework for assessments, design, geotechnical support, monitoring and procurement.#16STN TSX NYSE Q4 AND YEAR END 2023 Major Project Awards • • Stantec selected to design £4 billion battery manufacturing facility in the United Kingdom for Agratas, Tata Group's global manufacturing business. 3.2 million square foot facility will support United Kingdom's green energy transition; one of the largest facilities in Europe. • Stantec will provide architecture, mechanical, electrical, plumbing, structural, and civil engineering services, as well as risk management, planning compliance, BIM management, landscape architecture, and more. • Stantec's industry-leading architectural and engineering teams provide significant knowledge in advanced manufacturing design, helping clients improve their operations, reduce costs and optimize production flows. AGRATAS 16#1717 Q4 2023 STN TSX NYSE 2024 Financial Targets Net revenue growth Previously Published 2024 Annual Range 2024 ANNUAL RANGE 7% to 12% 11% to 15% Adjusted EBITDA as % of net revenue1 16.2% to 17.2% 16.2% to 17.2% Adjusted net income as % of net revenue1 above 8% above 8.0% Adjusted diluted EPS growth1 Adjusted ROIC1 11% to 16% 12% to 16% above 11.0% above 11.0% 1. Adjusted EBITDA, adjusted net income, adjusted diluted EPS, and adjusted ROIC are non-IFRS and other financial measures (discussed in the Definition section of our 2023 Annual Report). TOMO#18STN TSX NYSE 18 Theresa Jang CFO Planned Retirement Theresa will remain as chief financial officer until her successor is in place, ensuring a smooth transition#19STN TSX-NYSE 19 Q&A Sonia Sotomayor Middle School Prince George's County, Maryland, US