Mr. Adam Borgatti reports

AECON ANNOUNCES BOARD CHAIR TRANSITION

Aecon Group Inc. chairman John M. Beck will not stand for re-election to Aecon's board of directors at the annual meeting of shareholders on June 1, 2026 (the AGM). As part of the transition, Scott Thon, lead director, will step into the role of independent chair of the board, assuming his re-election to the board by shareholders at the AGM.

In recognition of his dedicated service and contributions to Aecon's success over his 60-year career, the board will confer upon Mr. beck the title of "chairman emeritus."

"Serving Aecon throughout my career has been a tremendous point of pride and helping to shape the company's evolution has been a true honour," said John M. Beck, chairman, Aecon Group. "I thank our shareholders for their trust, Aecon's talented leadership team for their commitment and our employees for their collective contributions over the years. I firmly believe that Aecon is stronger than ever before, and I am confident Scott Thon and the board of directors will guide Aecon's strategic growth to deliver lasting value to shareholders in the years to come."

"John has overseen Aecon's strategic direction and operations for over six decades, providing exceptional leadership through significant transformation and growth. His vision has delivered some of the most remarkable landmark projects of this generation," said Scott Thon, lead director, Aecon Group. "Throughout his award-winning career, John has established a world-class company with a distinguished reputation as an industry icon. John's legacy will forever be linked to Aecon's success. Personally, and on behalf of the entire board of directors, I want to thank John for his vast contributions to our customers, employees and shareholders."

After graduating from McGill University's civil engineering program in 1963, Mr. Beck joined his family's Prefac Concrete business in Montreal and embarked on a strategy of mergers, acquisitions and organic growth that grew the scale, geographic presence and market diversity of the business across Canada. After acquiring the company's brand predecessor, Armbro, the company was listed on the Toronto Stock Exchange in 1987. In 2001, Armbro officially changed its name to Aecon, amalgamating several acquired businesses. Mr. Beck has guided Aecon over the years in its evolution as a diverse and multidisciplinary North American company with global expertise -- serving as founder, former chief executive officer and executive chairman.

"John is a trailblazer in our industry. His mentorship, counsel and deep expertise have been invaluable to me -- and continuing to lead this exceptional company is my distinct privilege," said Jean-Louis Servranckx, president and chief executive officer, Aecon Group. "On behalf of Aecon's executive management team, I congratulate John on his extraordinary career as he transitions to chairman emeritus. Aecon looks forward to continuing to execute our growth strategy to advance our evolution."

Mr. Thon joined Aecon's board in 2021 and has served as lead director since 2024. He has held a number of senior positions in the energy sector over the last 40 years, and is currently an executive officer and director of Berkshire Hathaway Energy.

About Aecon Group Inc.

Aecon Group is a North American construction and infrastructure development company with global experience. Aecon delivers integrated solutions to private and public-sector clients through its construction segment in the civil, urban transportation, nuclear, utility and industrial sectors, and provides project development, financing, investment, management, and operations and maintenance services through its concessions segment.

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