First Phosphate Closes Third Tranche of Oversubscribed Private Placement

THIS NEWS RELEASE IS NOT INTENDED FOR DISTRIBUTION TO UNITED STATES

Saguenay, Quebec--(Newsfile Corp. - December 15, 2025) - First Phosphate Corp. (CSE: PHOS) (OTCQX: FRSPF) (FSE: KD0) ("First Phosphate" or the "Company") is pleased to announce that, on December 12, 2025, it closed the third tranche of its non-brokered private placement financing (the "Offering"), as further described in the Company's news releases dated November 7, 2025, November 17, and November 24, 2025.

In aggregate, under the three tranches of the Offering, the Company has raised gross proceeds of $6,637,574 through the issuance of 5,955,444 Flow-Through Shares for gross proceeds of $5,359,900, and through the issuance of 1,419,638 Hard Dollar Units for gross proceeds of $1,277,674. Under this tranche of the financing, the Company raised a total of $3,066,726 through the issuance of 2,599,612 Flow-Through Shares for gross proceeds of $2,339,651 and 807,861 Hard Dollar Units, comprised of 807,861 Common Shares and 807,861 Warrants, for gross proceeds of $727,075.

Together with this Offering, the Company has raised to date a total of approximately $46.7 million in 10 management-led non-brokered private-placement financings since June 2022.

In connection with the current tranche of the Offering, the Company issued 8,000 compensation common shares and 8,000 Compensation Warrants, exercisable at a price of $1.25 per common share of the Company, until April 30, 2026, subject to an Accelerated Expiry Date. All securities issued under the Offering are subject to a four-month and one day statutory hold period in accordance with applicable securities laws. The Company intends to use the proceeds from the Offering as disclosed in the Company's press release dated November 7, 2025. Capitalized terms used in this news release and not defined herein have the meanings given to them in the Company's news release dated November 7, 2025. The Company may close another tranche of the Offering at its discretion.

This news release does not constitute an offer to sell or a solicitation of an offer to sell any of securities in the United States. The securities 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 or to U.S. Persons unless registered under the U.S. Securities Act and applicable state securities laws or an exemption from such registration is available. Completion of the Offering is subject to certain conditions including, but not limited to, the receipt of all necessary approvals. There can be no assurance that any further securities will be sold under Offering.