AltaGas Announces Closing of $460 Million Equity Financing with Positive Credit Rating Updates

Press Release

Fitch and S&P Provide Positive Updates to Ratings Outlooks Following MVP Retention, Financing Plan and Advancement of Organic Growth Projects

CALGARY, AB, Nov. 7, 2025  – AltaGas Ltd. (“AltaGas” or the “Company”) (TSX: ALA) announced that the Company has completed its previously announced bought deal offering of 11,615,000 common shares of AltaGas (“Common Shares”), including 1,515,000 Common Shares issued through the exercise of the over-allotment option by the Underwriters. The offering was completed at $39.65 per Common Share (the “Offering Price”) for total gross proceeds of approximately $460 million (the “Public Offering”).

The Public Offering was announced on November 3, 2025 when AltaGas entered an agreement with a syndicate of underwriters led by CIBC Capital Markets, TD Securities Inc., RBC Capital Markets and Scotiabank (collectively, the “Underwriters”). As highlighted within AltaGas’ November 3, 2025, press release, the Public Offering was done in conjunction with AltaGas electing to retain its ownership in the Mountain Valley Pipeline (“MVP”) as a long-term investment.

The net proceeds of the Public Offering will be used by AltaGas to reduce leverage and to fund future growth. These actions are expected to deliver the same net near-term de-leveraging as would have been achieved through a full monetization of MVP with stronger long-term leverage reduction through MVP ownership once the expansion projects come online, ultimately enhancing AltaGas’ credit metrics and investment capacity to fund future growth projects.

AltaGas is Excited to Retain MVP as Long-term Investment

As previously highlighted, AltaGas is excited to remain an owner of MVP and believes retaining the assets will deliver superior value to its shareholders. Following a comprehensive sales process, AltaGas has elected to retain its ownership in MVP, including the MVP Mainline, MVP Boost, and MVP Southgate projects. The Company was pleased by robust demand from a broad set of buyers throughout the sale process. However, recent developments released over the past month have altered AltaGas’ view of proceeding with a monetization. As such, retaining MVP with its attractive near-term expansion projects will enhance shareholder value.

Key highlights on the strategic rationale to keep MVP include: 1) MVP Boost exceeding AltaGas’ expectations and being set to deliver strong project-level returns; 2) progress on MVP Southgate continuing constructively; and 3) the MVP Mainline showing strong outperformance. As such, retaining MVP with its attractive near-term expansion projects will enhance shareholder value.

AltaGas now expects project-level MVP EBITDA to increase significantly by the second half of 2028, following completion of the two expansion projects. As such, even assuming a monetization at the highest valuation multiple achieved for a minority pipeline monetization in recent years, on a 2026 multiple, a sale of AltaGas’ stake would be a low multiple on projected run-rate EBITDA following the now near-term expansions, inclusive of the Company’s net future investments – further reinforcing the superior value of continued ownership. By raising equity to achieve the same near-term leverage reduction as a monetization, AltaGas anticipates $0.02 higher normalized EPS in 2026, $0.03 higher normalized EPS in 2027, and $0.05 higher normalized EPS in 2028+, once expansions are online, than what would have been achieved through a divestiture. Retaining MVP is also expected to drive enhanced deleveraging as these projects come into service and the cash flow rises.

Credit Rating Actions

Following the announcement of AltaGas’ intention to retain ownership in MVP, the Public Offering, and the Company’s third quarter of 2025 results, S&P Global Ratings (“S&P”) and Fitch Ratings, Inc. (“Fitch”) released revisions to their respective credit outlooks, including:

• S&P: Revising AltaGas’ ratings outlook to “Positive” from “Negative”, while affirming its ratings of BBB-, supported by an improvement in S&P’s FFO-to-Debt outlook over the next 24 months as growth projects come into service, while minimizing business risk; and
• Fitch: Revising AltaGas’ ratings outlook to “Stable” from “Negative”, while affirming its ratings of BBB, supported by AltaGas’ expectation of improving FFO leverage, reinforced by the recent equity issuance, stable utility cash flows, strong demand for LPG exports, and AltaGas’ retained 10% ownership in MVP.

Canadian Securities Disclosures

For further information regarding the Common Shares, including related risk factors, refer to AltaGas’ prospectus supplement dated November 5, 2025 (the “Prospectus Supplement”) to the base shelf prospectus of AltaGas dated March 12, 2025 (the “Base Shelf Prospectus”). The Base Shelf Prospectus and the Prospectus Supplement are accessible on SEDAR+ at www.sedarplus.ca.

This news release does not constitute an offer to sell or the solicitation of an offer to buy the Common Shares. The Common Shares have not been approved or disapproved by any regulatory authority.

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 energy infrastructure business that is focused on delivering stable and growing 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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