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October 10, 2024

ATCO TO RELEASE THIRD QUARTER 2024 RESULTS ON NOVEMBER 14, 2024

CALGARY, Alberta - ATCO Ltd. (TSX: ACO.X) (TSX: ACO.Y)

ATCO Ltd. (ATCO) will release its financial results for the quarter ended September 30, 2024, on Thursday, November 14, 2024. The news release will be distributed via Cision (www.newswire.ca/news-releases/) and the results, including Financial Statements and Management's Discussion & Analysis, will be posted on www.ATCO.com.

ATCO will hold a live teleconference and webcast with Katie Patrick, Executive Vice President, Chief Financial & Investment Officer and Adam Beattie, President, Structures at 10:00 am Mountain Time (12:00 pm Eastern Time) on Thursday, November 14, 2024 at 1-844-763-8274. No pass code is required.

Opening remarks will be followed by a question and answer period with investment analysts. Participants are asked to please dial-in 10 minutes prior to the start and request to join the ATCO teleconference.

Management invites interested parties to listen via live webcast at: https://www.atco.com/en-ca/about- us/investors/events-presentations.html.

A replay of the teleconference will be available approximately two hours after the conclusion of the call until December 14, 2024. Please call 1-855-669-9658 and enter pass code 8509779.

As a global enterprise ATCO Ltd. and its subsidiary and affiliate companies have approximately 20,000 employees and assets of $26 billion. ATCO is committed to future prosperity by working to meet the world's essential energy, housing, security and transportation challenges. ATCO Structures designs, builds and delivers products to service the essential need for housing and shelter around the globe. ATCO Frontec provides operational support services to government, defence and commercial clients. ATCO Energy Systems delivers essential energy for an evolving world through its electricity and natural gas transmission and distribution, and international operations. ATCO EnPower creates sustainable energy solutions in the areas of renewables, energy storage, industrial water and alternative fuels. ATCO Australia develops, builds, owns and operates energy and infrastructure assets. ATCOenergy and Rumi provide retail electricity and natural gas services, home maintenance services and professional home advice that bring exceptional comfort, peace of mind and freedom to homeowners and customers. ATCO also has investments in ports and transportation logistics, the processing and marketing of fly ash, retail food services and commercial real estate. More information can be found at www.ATCO.com.

Investor & Analyst Inquiries: Colin Jackson Senior Vice President, Financial Operations Colin.Jackson@atco.com (403) 808 2636

Media Inquiries: Kurt Kadatz Director, Corporate Communications Kurt.Kadatz@atco.com (587) 228 4571

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