Mr. Leigh Curyer reports

NEXGEN ANNOUNCES UPSIZED C$224 MILLION CDI OFFERING IN AUSTRALIA

NexGen Energy Ltd. has entered into an amended and restated placement agreement dated April 30, 2024, with a lead manager and bookrunner in Australia, Aitken Mount Capital Partners, to upsize its previously announced Australian offering to be 20,161,290 common shares of the company at a price of $11.11 per share (based on the daily average exchange rate of $1 (Australian) to 89.63 cents published by the Bank of Canada on April 29, 2024) for aggregate gross proceeds of approximately $224-million. Canaccord Genuity acted as Lead Co-Manager to the Offering.

The Offering will be marketed to Australian investors to enhance the liquidity, trading volumes and market capitalization of the Company's CHESS Depositary Interests ("CDIs") listed on the ASX and will be done in accordance with the terms of the Placement Agreement. The net proceeds of the Offering will be used to fund the continued development and further exploration of the Company's mineral properties, and for general corporate purposes.

Closing of the Offering is expected to occur on or about May 15, 2024, with settlement to occur through newly-issued CDIs listed on the ASX. The ASX uses an uncertificated electronic system called CHESS for the electronic clearance and settlement of trades on the ASX in depositary instruments know as CDIs. CDIs represent the beneficial interest in an underlying Share, which are traded in a manner similar to shares in an Australian company listed on ASX. Each CDI represents a unit of beneficial ownership in one underlying Share.

The Shares will be issued pursuant to a prospectus supplement (the "Prospectus Supplement") to the Company's final short form base shelf prospectus to be filed in all provinces and territories of Canada dated December 8, 2023 (the "Base Shelf Prospectus"). The CDIs will not be qualified by the Prospectus Supplement or the Base Shelf Prospectus, and may not be offered or sold in Canada. Resales of CDIs in Canada will be restricted under applicable Canadian securities laws.

Issuance of the Shares is subject to a number of conditions, including receipt of customary TSX and NYSE approvals. The Lead Manager may terminate its obligations under the Placement Agreement, at its discretion, on the basis of certain "market out", "disaster out", and "regulatory out" conditions, in addition to the occurrence of certain stated events.

Concurrent Amendment to ATM Program to Facilitate Offering

To create room for the Shares to be distributed under the Base Shelf Prospectus, the Company, Virtu Canada Corp., as Canadian agent, and Virtu Americas, LLC, as U.S. agent (together, the " Agents ") have agreed to amend the Company's previously announced at-the-market program (the " ATM Program ") by reducing the aggregate value of common shares that may be offered and sold from up to C$500,000,000 to up to C$275,925,000 in common shares by amending, as of April 29, 2024, the equity distribution agreement dated December 11, 2023 between the Company and the Agents (the " Amended Sales Agreement "). The volume and timing of sales under the ATM Program, if any, will be determined in the Company's sole discretion, and at the market price prevailing at the time of each sale, and, as a result, sale prices may vary. To date, an aggregate of 13,000,800 common shares of the Company have been distributed under the ATM Program, for aggregate gross proceeds of C$134,948,304 (the " Prior Sales "). Offers and sales under the ATM Program, if any, may be made on the TSX and/or the NYSE, and/or any other marketplace for the common shares in Canada or the United States as agreed to between the Agents and the Company, pursuant to a prospectus supplement dated December 11, 2023 (the " ATM Prospectus Supplement ") to the Company's Base Shelf Prospectus and a prospectus supplement (the " U.S. ATM Prospectus Supplement ") to the Company's U.S. Base Prospectus included in the Registration Statement filed with the United States Securities and Exchange Commission on December 8, 2023 (collectively, the ATM Prospectus Supplement, Base Shelf Prospectus, U.S. ATM Prospectus Supplement, the U.S. Base Prospectus and Registration Statement, the " ATM Offering Documents "). As a result of the Amended Sales Agreement and taking into account the Prior Sales, the maximum amount of sales remaining under the ATM Program will be C$140,976,696.

As outlined in the ATM Offering Documents, the Company intends to use the net proceeds from the ATM Program, if any, to fund the continued development and further exploration of its mineral properties, and for general corporate purposes. The ATM Program will be effective until the earlier of (i) the sale of all of the common shares in the capital of the Company issuable pursuant to the ATM Program (as amended by the Amended Sales Agreement) and (ii) January 8, 2026, unless terminated prior to such date by the Company or the Agents.

The ATM Prospectus Supplement, the Base Shelf Prospectus and the Sales Agreement are available at www.sedarplus.ca and the U.S. ATM Prospectus Supplement, the U.S. Base Prospectus and the Registration Statement are available at www.sec.gov . Alternatively, the Agents will send copies of the ATM Prospectus Supplement and the Base Shelf Prospectus or the U.S. ATM Prospectus Supplement and the U.S. Base Prospectus, as applicable, upon request by contacting: Virtu Canada Corp.; Attn Capital Markets; 222 Bay Street | Suite 1720 | Toronto, ON M5K 1B7; ATMCanada@Virtu.com or Virtu Americas, LLC; Attn Capital Markets; 1633 Broadway | New York, NY 10019; ATM@Virtu.Com .

Potential investors should read the ATM Offering Documents, Amended Sales Agreement and other documents the Company has filed publicly, available at www.sedarplus.ca and www.sec.gov , for more complete information about the Company and the ATM Program.

Legal Advisors

Farris LLP acted as legal counsel to the Company. Blake, Cassels & Graydon LLP (Canadian counsel) and Skadden, Arps, Slate, Meagher & Flom LLP (U.S. counsel) served as legal advisors to the Agents in connection with the ATM Program.

About NexGen

NexGen is a British Columbia corporation focused on the development of the Rook I Project located in the southwestern Athabasca Basin, Saskatchewan, Canada, into production.

We seek Safe Harbor.