AltaGas Announces $500 Million Medium Term Note Offering

Press Release

CALGARY, AB, Nov. 6, 2025 – AltaGas Ltd. (“AltaGas”) (TSX: ALA) today announced that it has agreed to issue $500 million of senior unsecured medium term notes (the “Offering”) with a coupon rate of 3.025 percent, maturing on November 10, 2027.

The Offering is expected to close on or about November 10, 2025. The net proceeds resulting from the Offering will be used to repay existing indebtedness including indebtedness under AltaGas’ credit facilities, to fund working capital and for general corporate purposes.

The Offering is being made through a syndicate of investment dealers co-led by TD Securities Inc. and National Bank Financial Inc. under AltaGas’ Short Form Base Shelf Prospectus dated March 12, 2025, Prospectus Supplement dated November 6, 2025 and related Pricing Supplement dated November 6, 2025.

This news release does not constitute an offer to sell or the solicitation of an offer to buy any of the offering in any jurisdiction. The offering has not been approved or disapproved by any regulatory authority or will be registered under the United States Securities Act of 1933, as amended (the “U.S. Securities Act”), or any state securities laws, and may not be offered or sold within the United States unless an exemption from the registration requirements of the U.S. Securities Act is available.

All financial figures are in Canadian dollars.

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.

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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