Mr. Leigh Curyer reports

NEXGEN COMMENCES EXPANDED 43,000 METER DRILL PROGRAM AT PATTERSON CORRIDOR EAST

NexGen Energy Ltd. has begun a 43,000-metre exploration drill program to continue to test the extent and growth of mineralization discovered in early 2024 at Patterson Corridor East (PCE), located 3.5 kilometres east of the world-class Arrow deposit. This systematic program represents an increase of 9,000 m from the 2024 program and is expected to be one of the largest drill programs in the Athabasca basin, Saskatchewan, in 2025. The initial results at PCE revealed vein-type uranium mineralization intersected within the competent basement rock, highly analogous to Arrow. Since discovery, the mineralized footprint at PCE has rapidly grown to 600 m along strike and 600 m of vertical extent (see Nov. 12, 2024, news release).

Drilling in 2025 will focus on testing the extent of the mineralized footprint, further investigating high-grade zones within the broad mineralized footprint and determining potential for additional mineralization within the same target area. Since discovery and over the 2024 campaign, 19 of the 30 initial holes intersected mineralization, with 10 intersecting intermittent widths of high grade of greater than 10,000 cps (counts per second) mineralization. In addition, strategic use of geophysics will cover prospective areas on SW3 to refine a growing inventory of drill-ready targets across NexGen's dominant southwestern Athabasca basin land position. Assays for 2024 drilling will be reported once fully received in the first quarter of 2025.

Leigh Curyer, chief executive officer, commented: "In early 2024, we launched a bold grassroots exploration program aimed at discovering new uranium resources to address the material and growing uranium demand/supply gap. NexGen's disciplined and systematic approach to evaluating high-priority targets resulted in the discovery and material growth of mineralization at PCE. This highly prospective area continues to be the central focus of our exploration efforts given the clear potential demonstrated to date at PCE. This is a strategic focus to contribute sustainable supply to the growing demand for uranium to fuel the global energy needs."

Jason Craven, vice-president, exploration, commented: "The scale of this year's drill program speaks to our excitement for PCE and a commitment to efficiently and thoroughly assess it. Continuity of mineralization, as well as intensity of high-grade mineralization and alteration, indicate a system with strong potential for continued growth. These are compelling early days at PCE, where we will remain solely focused on unlocking its full potential."

With over $800-million in cash and liquid assets, NexGen is optimally financed for the continuing development of the Rook I project as well as the PCE exploration program, and for general corporate purposes.

About NexGen Energy Ltd.

NexGen Energy is a Canadian company focused on delivering clean-energy fuel for the future. The company's flagship Rook I project is being optimally developed into the largest low-cost producing uranium mine globally, incorporating the most elite standards in environmental and social governance. The Rook I project is supported by a National Instrument 43-101-compliant feasibility study which outlines the elite environmental performance and industry-leading economics. NexGen is led by a team of experienced uranium and mining industry professionals with expertise across the entire mining life cycle, including exploration, financing, project engineering and construction, operations, and closure. NexGen is leveraging its proven experience to deliver a project that leads the entire mining industry socially, technically and environmentally. The project and prospective portfolio in Northern Saskatchewan will provide generational long-term economic, environmental and social benefits for Saskatchewan, Canada, and the world.

Technical disclosure

All technical information in this news release has been reviewed and approved by Jason Craven, NexGen's vice-president, exploration, a qualified person under NI 43-101.

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