Mr. Harold Fortin reports

ATKINSREALIS ANNOUNCES AGREEMENT TO REPURCHASE 7,000,000 OF ITS SHARES HELD BY LA CAISSE

Atkinsrealis Group Inc. has entered into a private agreement with Caisse de depot et placement du Quebec for the repurchase for cancellation of seven million common shares of Atkinsrealis held by the Caisse at a price of $90.87 per share for total consideration of approximately $636-million. The repurchase price represents a discount of 3 per cent to the closing price of the shares on the Toronto Stock Exchange on June 25, 2025, and will be paid using cash on hand.

The repurchase will be made in connection with the periodic portfolio rebalancing of the Caisse. Once the repurchase is completed, the Caisse will hold approximately 27.4 million common shares, representing approximately 16.5 per cent of Atkinsrealis's total common shares outstanding.

"This transaction with La Caisse, a leading shareholder of Atkinsrealis, is consistent with our capital allocation framework outlined at our 2024 investor day and represents an opportunity to create shareholder value. Our strong balance sheet following the recent sale of our interest in Highway 407 ETR allows us to be well positioned to take advantage of opportunities like this. We will also continue to pursue our global growth strategy from our head office, which has a dedicated strong management team based in Montreal," said Ian L. Edwards, president and chief executive officer of Atkinsrealis.

"La Caisse has been a key partner of Atkinsrealis for nearly three decades, during which time our investment has significantly contributed to the company's growth and success," said Kim Thomassin, executive vice-president and head of Quebec at the Caisse. "We are now monetizing part of our investment while remaining the company's shareholder of reference, reflecting our continued confidence in its prospects."

A favourable decision was obtained from the Autorite des marches financiers to exempt Atkinsrealis from issuer bid requirements under applicable securities legislation applicable to the transaction, which will be made at a discount in accordance with the decision.

Information regarding the share repurchase, including the number of common shares repurchased and the aggregate repurchase price paid, will be available on SEDAR+ following the completion thereof. Atkinsrealis will not issue any additional press release announcing the completion of this share repurchase.

Following the share repurchase, the company will cease to repurchase its common shares from the Caisse in accordance with an exemption granted by the Toronto Stock Exchange in March, 2025, in connection with its normal course issuer bid that commenced on March 17, 2025, which allowed the Caisse to maintain its proportionate shareholding percentage of the issued and outstanding common shares.

About Atkinsrealis Group Inc.

Created by the integration of long-standing organizations dating back to 1911, Atkinsrealis is a world-class engineering service and nuclear company dedicated to engineering a better future for the planet and its people. It creates sustainable solutions that connect people, data and technology to transform the world's infrastructure and energy systems. The company deploys global capabilities locally to its clients and delivers unique end-to-end services across the whole life cycle of an asset, including consulting, advisory and environmental services, intelligent networks and cybersecurity, design and engineering, procurement, project and construction management, operations and maintenance, decommissioning, and capital. The breadth and depth of its capabilities are delivered to clients in strategic sectors such as engineering services, nuclear and capital.

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