Mr. Philip Williams reports

ISOENERGY ANNOUNCES NEW AT-THE-MARKET EQUITY PROGRAM

IsoEnergy Ltd. has entered into an equity distribution agreement with Virtu Canada Corp. and Virtu Americas LLC. Pursuant to the distribution agreement, the company may distribute up to $50-million (Canadian) (or its equivalent in other currencies) of common shares in the capital of the company, from time to time through the agents. This ATM (at-the-market) program replaces the company's previous at-the-market equity program announced on June 2, 2025, which has since been terminated.

Philip Williams, chief executive officer and director of IsoEnergy, commented: "Maintaining an at-the-market equity program provides IsoEnergy with additional financial flexibility and an efficient supplemental capital markets tool that can be used selectively, if and when appropriate. With a strong cash position of $135.1-million (1) and equity portfolio of $52.6-million (2), we are well funded to execute on our current plans and the ATM program is not being established to address any immediate capital requirements. Instead, it preserves optionality, allowing the company to act opportunistically in support of future growth, strategic initiatives and balance sheet strength."

Any common shares sold through the ATM program will be sold: (i) through ordinary brokers' transactions on the NYSE American LLC or another U.S. marketplace, as such term is defined in National Instrument 21-101, Marketplace Operation; (ii) through ordinary brokers' transactions on the Toronto Stock Exchange that constitute at-the-market distributions as defined in National Instrument 44-102, Shelf Distributions; (iii) on another Canadian marketplace, as such term is defined in NI 21-101, upon which the common shares are listed, quoted or otherwise traded; or (iv) otherwise at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices.

(1) As disclosed in IsoEnergy's management's discussion and analysis for the year ended Dec. 31, 2025, dated Feb. 26, 2026.

(2) The equity portfolio consists of marketable securities in NexGen Energy Ltd., Premier American Uranium Inc., Atha Energy Corp., Jaguar Uranium Corp., Toro Energy Ltd., Purepoint Uranium Group Inc., Future Fuels Inc., Royal Uranium Inc., Verdera Energy Corp. and Biondi Ventures Inc., as disclosed in IsoEnergy's audited consolidated financial statements for the year ended Dec. 31, 2025.

The volume and timing of sales under the ATM program, if any, will be determined at the company's sole discretion and in accordance with the terms of the distribution agreement. The TSX has conditionally approved the listing of the common shares that may be issued under the ATM program and the company has applied for authorization from the NYSE American for the listing of such common shares. The company is not obligated to make any sales of common shares under the ATM program. The ATM program will be effective until the earlier of the issuance and sale of all of the common shares issuable pursuant to the ATM program and the date that the ATM program is otherwise terminated pursuant to the terms of the distribution agreement.

The company intends to use the net proceeds from the ATM program, if any, for general corporate purposes, which may include financing of corporate and project overhead expenses, financing of capital expenditures, repayment of indebtedness, technical studies and exploration in the United States and Australia, and additions to working capital.

The ATM program is being established pursuant to a prospectus supplement dated April 17, 2026, to the company's short form base shelf prospectus dated Jan. 13, 2026, as filed with the securities regulatory authorities in each of the provinces and territories of Canada, and pursuant to a prospectus supplement dated April 17, 2026, to the company's U.S. base prospectus included in its registration statement on Form F-10, and filed with the U.S. Securities and Exchange Commission (SEC) on Jan. 13, 2026.

The company has filed the registration statement (including the U.S. base shelf prospectus) and the U.S. prospectus supplement to which this communication relates with the SEC. Before you invest, you should read the registration statement, the U.S. prospectus supplement and other documents the issuer has filed with the SEC, as well as the corresponding documents filed in Canada, for more complete information about the company and this offering. The Canadian prospectus supplement and base shelf prospectus may be downloaded for free from SEDAR+, and the U.S. prospectus supplement and the registration statement are accessible for free via EDGAR. Alternatively, the company will send you copies of such documents upon request made to the company, and the agents will send copies of such documents to investors upon request by contacting Virtu Canada at Suite 1720, 222 Bay St., Toronto, Ont., M5K 1B7, by e-mail at ATMCanada@virtu.com or by telephone at 646-682-6322, or by contacting Virtu Americas on the 41st floor of 1633 Broadway, New York, N.Y., 10019, U.S., by e-mail at ATM@Virtu.com or by telephone at 646-682-6322.

About IsoEnergy Ltd.

IsoEnergy is a leading, globally diversified uranium company with substantial current and historical mineral resources in top uranium mining jurisdictions of Canada, the United States and Australia at varying stages of development, providing near-, medium- and long-term leverage to rising uranium prices. IsoEnergy is currently advancing its Larocque East project in Canada's Athabasca basin, which is home to the Hurricane deposit, boasting the world's highest-grade indicated uranium mineral resource. IsoEnergy also holds a portfolio of permitted past-producing, conventional uranium and vanadium mines in Utah with a toll milling arrangement in place with Energy Fuels. These mines are currently on standby, ready for rapid restart as market conditions permit, positioning IsoEnergy as a near-term uranium producer.

We seek Safe Harbor.