Tourmaline Announces Issuance of Senior Unsecured Notes

Press Release

Calgary, Alberta – Tourmaline Oil Corp. (TSX – TOU) (“Tourmaline” or the “Company”) is pleased to announce that it has agreed to issue $250 million aggregate principal amount of senior unsecured notes due March 16, 2031 (the “Notes”). The Notes will be issued at par for aggregate gross proceeds of $250 million and will bear interest at a fixed rate of 3.934% per annum, payable semi-annually on the 16th day of March and September of each year, commencing on September 16, 2026.

Tourmaline continues its strategy of diversifying its sources of low-cost capital and continuing its progression as one of the largest, most efficient producers of oil and gas in North America. The Notes have been assigned a provisional rating of BBB (High), with a stable trend, by DBRS Limited (Morningstar DBRS).

The Notes will be direct, unsecured obligations of Tourmaline and will rank equally with all other present and future unsecured and unsubordinated indebtedness of the Company. The Notes are being offered in Canada on a private-placement basis in reliance upon exemptions from the prospectus requirements under applicable securities legislation (the “Offering”).

The Notes, offered on a best-efforts basis through a syndicate of agents co-led by Scotiabank, CIBC Capital Markets and National Bank Capital Markets, are expected to be issued on or about March 16, 2026, subject to customary closing conditions. The net proceeds of the Offering will be used to repay existing indebtedness and for general corporate purposes. The Company has set a long-term net debt(1) target of $1.75 billion (approximately 0.5x net debt to cash flow(2)).

This news release does not constitute an offer to sell or the solicitation of an offer to buy any of the Notes in any jurisdiction. The Notes have not been approved or disapproved by any regulatory authority. The Notes have not been and will not 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.

(1) “Net debt” is a capital management measure. See “Non-GAAP and Other Financial Measures” in this news release and in the Company’s Annual 2025 Management’s Discussion and Analysis.

(2) “Cash flow” is a non- GAAP financial measure. See “Non-GAAP and Other Financial Measures” in this news release and in the Company’s Annual 2025 Management’s Discussion and Analysis.

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CURRENCY

All financial figures are in Canadian dollars.

FOR FURTHER INFORMATION, PLEASE CONTACT:

Tourmaline Oil Corp.

Michael Rose

Chairman, President and Chief Executive Officer

(403) 266-5992

Tourmaline Oil Corp.

Brian Robinson

Chief Financial Officer

(403) 767-3587; brian.robinson@tourmalineoil.com

Tourmaline Oil Corp.