AltaGas Activates Contingency Plan to Maintain Uninterrupted Ripet Export Operations Amid Labour Disruption

Press Release

CALGARY, AB, Nov. 25, 2025 – AltaGas Ltd. (“AltaGas” or the “Company”) (TSX: ALA) has activated its contingency plan to maintain steady operations at the Ridley Island Propane Export Terminal (“RIPET”) in response to a pending labour disruption. The International Longshore and Warehouse Union (“ILWU”) Local 523B, representing RIPET union employees, has initiated strike action and elected to proceed with a labour strike on November 27, 2025.

While AltaGas is disappointed that a resolution has not yet been reached, the Company remains committed to working collaboratively with its union partner to achieve a fair agreement that benefits all stakeholders over the long-term. In the interim, contingency measures have been enacted, and an alternate workforce is in place that are expected to maintain materially consistent export operations and ensure AltaGas continues to deliver safe and reliable service to its more than 70 export customers that utilize the open-access terminal. As a result of the contingency plan being enacted, the Company expects minimal financial impact and is reiterating its 2025 full-year guidance range.

With growing economic and energy ties between Canada and Asia, RIPET plays a critical role in providing consistent egress for Canadian propane production to reach the highest-value global markets. This enables Canadian producers and aggregators to realize stronger pricing for their products, benefiting all Canadians while providing vital energy security and diversification in Asia. By AltaGas continuing to take actions to maintain ratable service during the labour disruption, the Company is ensuring that Canadian-Asian trading relations continue to deepen, and that Canada is seen as a stable energy supplier to meet long-term energy demand needs in Asia.

ABOUT ALTAGAS

AltaGas is a leading North American infrastructure company that connects customers and markets to affordable and reliable sources of energy. The Company operates a diversified, lower-risk, high-growth Utilities and Midstream business that is focused on delivering resilient and durable value for its stakeholders. From wellhead to tidewater, AltaGas’ Midstream business is focused on providing its customers with safe and reliable service and connectivity that facilitates the best outcomes for their businesses. This includes global open-market access for North American LPGs, which provides North American producers and aggregators with the best netbacks for LPGs while delivering diversity of supply and stronger energy security to its downstream customers in Asia.

For more information visit www.altagas.ca or reach out to one of the following:

Jon Morrison
Senior Vice President, Corporate Development and Investor Relations
Jon.Morrison@altagas.ca

Aaron Swanson
Vice President, Investor Relations
Aaron.Swanson@altagas.ca

Investor Inquiries
1-877-691-7199
investor.relations@altagas.ca

Media Inquiries
1-403-206-2841
media.relations@altagas.ca

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