Mr. Grant Greenwood reports

NEXGEN SUMMER DRILLING COMMENCES - 17,000M

NexGen Energy Ltd. has commenced a summer exploration drill program comprising 17,000 metres on its 100-per-cent-owned SW2 and SW1 properties in the southwest Athabasca basin, Saskatchewan. Geophysical surveys and historical drilling review have refined prospective areas for immediate drill testing.

Grant Greenwood, vice-president, exploration, commented: "A comprehensive review and analysis of NexGen's exploration data was completed this spring, leading to a highly targeted summer drill program that will focus on high-priority areas of NexGen's extensive SW2 and SW1 land packages. NexGen has strategically advanced significant areas of its dominant land position in the southwest Athabasca basin towards the pursuit of material uranium discovery. Geophysical surveys have highlighted prominent, stacked anomalies for immediate testing in search of a large-scale economic discovery. We are excited to drill test these highly prospective targets throughout the summer."

2023 summer drilling

Drilling will systematically test highest priority areas of prospective corridors identified by an extensive geophysical survey program that began in 2022 and continued in 2023. Drill readiness has advanced across approximately 22,000 hectares of NexGen's properties, effectively supporting strategic evaluation of targets this year and in subsequent programs. Follow-up drilling of favourable historical results during winter 2023 will also be a priority for the summer drilling program.

A total of 17,000 metres is planned for the summer with up to three rigs in operation, bringing the 2023 exploration total planned metres to 22,500.

Drill target areas:

SW2 (location of Arrow, the Rook I project) -- Geophysical surveys have revealed prominent, stacked anomalies along the structurally complex R7 (previously referred to as R Seven) and Morrow corridors within the central area of NexGen's expansive SW2 property. Drill testing with aggressive, first-pass steps is planned for these two prospective corridors along with follow-up drilling of Arrow-proximal corridors where high prospectivity is present.

• R7 -- massive, complex structural corridor with about 45 kilometres of strike on SW2 that spans the Athabasca boundary. Recent high-resolution magnetics have highlighted structural kinematics, coincident with gravity anomalies, interpreted as effective traps of mineralization.
• Morrow -- over 10 kilometres of chained, stacked geophysical anomalies. Completely untested corridor with blue-sky potential.
• PLC East and Derkson West -- follow-up of favourable structure and alteration from winter 2023, potential proximal to Arrow.
• Derkson -- gravity low bull's-eye coincident with electromagnetic conductor near the Athabasca margin.
• Derkson East -- conductor offset and breaks align with gravity low.
• Fury -- conductor breaks within gravity lows along uniquely oriented trend.

SW1 -- Two thousand twenty-three summer drilling is planned along the underexplored Gartner and Gambit corridors.

• Gartner -- Two thousand twenty-three winter drilling successfully intersected prospective structure and hydrothermal alteration indicative of uranium-bearing systems and will be followed up along strike.
• Gambit -- an interpreted, 12-kilometre structural corridor on NexGen's SW1 property along strike of F3 Uranium Corp.'s JR zone discovery. A winter 2023 ground electromagnetic (EM) survey was conducted within the corridor to locate structural features that will be drill tested during the summer 2023 program.

A presentation providing details on the summer 2023 exploration program is available at the company's website.

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 Mr. Greenwood, NexGen's vice-president, exploration, a qualified person under National Instrument 43-101.

A technical report in respect of the feasibility study is filed on SEDAR and EDGAR and is available for review on NexGen Energy's website.

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