Vertical extent of high-grade subdomain increased by 94 m to 644 m with RK-26-293 intersecting cumulative 4.7 m of >10,000 cps, including 0.1 m of >61,000 cps at 930 m depth.

Down plunge test hole, RK-26-290c1, intersected multiple stacked uranium veins across 40 m of the high-grade subdomain intersecting cumulative 19.5 m of >10,000 cps including 12.9 m of >10,000 cps that surrounds 5.2 m of >61,000 cps.

Internal continuity strong throughout highlighted by RK-26-294 intersecting cumulative 6.9 m of >10,000 cps including 3.1 m of >61,000 cps located 27 m up dip of RK-24-222 (17.0 m at 3.85% U3O8).

Holes RK-26-290c1 and RK-26-294 represent the two best holes for 2026 to date, and rank as the best and third best holes, based on cumulative >61,000 cps, intersected at PCE since discovery.

Additionally, the up dip high-grade subdomain expanded by 50 m in RK-26-296 that returned cumulative 3.5 m of >10,000 cps including 0.4 m of >61,000 cps.

NexGen adding a fifth drill rig to continue to advance PCE optimally.

Vancouver, British Columbia--(Newsfile Corp. - August 25, 2026) - NexGen Energy Ltd. (TSX:NXE) (NYSE:NXE) (ASX: NXG) ("NexGen" or the "Company") announces results from the early portion of 2026 summer drilling at PCE which expanded the high-grade subdomain both up and down dip while continuing to demonstrate strong internal continuity of intense high-grade mineralization (Figures 1 and 2, Table 1).

High-grade uranium mineralization now extends to 930 m with hole RK-26-293 intersecting cumulative 4.7 m of >10,000 cps including 0.1 m of >61,000 cps. This hole expanded the vertical extent by 94 m, a 17% increase to 644 m. This zone of intense mineralization is accompanied by strong, broad hydrothermal alteration with notable potential for additional mineralized continuation nearby and below (Figures 1 and 2). The strike extent remains at 210 m as recent tests primarily focused on confirmation of deep-seated interpretations.

RK-26-290c1 designed as a down-plunge test in hole delivered a dual purpose as a test across the full extent of the previous known mineralized footprint of PCE in order to understand the geometry, continuity and extents of high-grade zones within the overall mineralization. This hole intersected multiple stacked uranium veins across 40 m of the high-grade subdomain with cumulative 19.5 m of >10,000 cps including 12.9 m of >10,000 cps that surrounds 5.2 m of >61,000 cps. This is the best hole to date at PCE based on >61,000 cps. Advancement of the model was optimized with confirmation of interpretations as well as critical identification of repeating, mineralization-controlling structural disruptions.

RK-26-294 delivered confirmation of strong internal continuity of intense mineralization intersecting cumulative 6.9 m of >10,000 cps including 3.1 m of >61,000 cps located 27 m along strike of RK-24-222 (17.0 m at 3.85% U3O8) (Figures 1 to 4). Together with RK-26-290c1, these holes combined represent the two best holes drilled to date in 2026.

Additional new drilling shown in Figures 1 and 2, and Table 1, tested the mineralized extents and key areas within the high-grade subdomain. These holes provided crucial geological orientation information that influences extents of the model, in particular the high-grade component. An example being RK-26-296 with cumulative 3.5 m of >10,000 cps including 0.4 m of >61,000 cps that expanded the shallowest portion of PCE by 50 m along strike. Overall, the bulk of high-grade subdomain mineralization at PCE is 70 m shallower than the A2 High-Grade (HG) Zone.