CORPORATE PRESENTATION | FORWARD LOOKING STATEMENTS

Forward-Looking Information

The information contained herein contains "forward-looking statements" within the meaning of applicable United States securities laws and regulations and "forward-looking information" within the meaning of applicable Canadian securities legislation. "Forward-looking information" includes, but is not limited to, statements with respect to mineral reserve and mineral resource estimates, the 2021 Arrow Deposit, Rook I Project and estimates of uranium production, grade and long-term average uranium prices, anticipated effects of completed drill results on the Rook I Project, planned work programs and development activities and budgets, Canadian Nuclear Safety Commission and other approvals, completion of further site investigations and engineering work to support basic engineering of the project and expected outcomes. Generally, but not always, forward-looking information and statements can be identified by the use of words such as "plans", "expects", "is expected", "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates", or "believes" or the negative connotation thereof or variations of such words and phrases or state that certain actions, events or results "may", "could", "would", "might" or "will be taken", "occur" or "be achieved" or the negative connotation thereof. Statements relating to "mineral resources" are deemed to be forward-looking information, as they involve the implied assessment that, based on certain estimates and assumptions, the mineral resources described can be profitably produced in the future.

Forward-looking information and statements are based on the then current expectations, beliefs, assumptions, estimates and forecasts about NexGen's business and the industry and markets in which it operates. Forward-looking information and statements are made based upon numerous assumptions, including among others, that the mineral reserve and resources estimates and the key assumptions and parameters on which such estimates are based are as set out in this presentation and the technical report for the property , the results of planned exploration activities are as anticipated, the price and market supply of uranium, the cost of planned exploration activities, that financing will be available if and when needed and on reasonable terms, that third party contractors, equipment, supplies and governmental and other approvals required to conduct NexGen's planned exploration activities will be available on reasonable terms and in a timely manner and that general business and economic conditions will not change in a material adverse manner. Although the assumptions made by the Company in providing forward looking information or making forward looking statements are considered reasonable by management at the time, there can be no assurance that such assumptions will prove to be accurate in the future.

Forward-looking information and statements also involve known and unknown risks and uncertainties and other factors, which may cause actual results, performances and achievements of NexGen to differ materially from any projections of results, performances and achievements of NexGen expressed or implied by such forward-looking information or statements, including, among others, the existence of negative operating cash flow and dependence on third party financing, uncertainty of the availability of additional financing, the risk that pending assay results will not confirm previously announced preliminary results, conclusions of economic valuations, the risk that actual results of exploration activities will be different than anticipated, the cost of labour, equipment or materials will increase more than expected, that the future price of uranium will decline or otherwise not rise to an economic level, the appeal of alternate sources of energy to uranium-produced energy, that the Canadian dollar will strengthen against the U.S. dollar, that mineral resources and reserves are not as estimated, that actual costs or actual results of reclamation activities are greater than expected, that changes in project parameters and plans continue to be refined and may result in increased costs, of unexpected variations in mineral resources and reserves, grade or recovery rates or other risks generally associated with mining, unanticipated delays in obtaining governmental, regulatory or First Nations approvals, risks related to First Nations title and consultation, reliance upon key management and other personnel, deficiencies in the Company’s title to its properties, uninsurable risks, failure to manage conflicts of interest, failure to obtain or maintain required permits and licences, risks related to changes in laws, regulations, policy and public perception, as well as those factors or other risks as more fully described in NexGen’s Annual Information Form dated March 3, 2026 filed with the securities commissions of all provinces and territories of Canada and in NexGen’s 40-F filed with the United States Securities and Exchange Commission, which are available on SEDAR+ at www.sedarplus.ca and Edgar at www.sec.gov.   

Although the Company has attempted to identify important factors that could cause actual results to differ materially from those contained in the forward-looking information or statements or implied by forward-looking information or statements, there may be other factors that cause results not to be as anticipated, estimated or intended. Readers are cautioned not to place undue reliance on forward-looking information or statements due to the inherent uncertainty thereof. There can be no assurance that forward-looking information and statements will prove to be accurate, as actual results and future events could differ materially from those anticipated, estimated or intended. Accordingly, readers should not place undue reliance on forward-looking statements or information. The Company undertakes no obligation to update or reissue forward-looking information as a result of new information or events except as required by applicable securities laws. 

This presentation includes Mineral Reserves and Mineral Resources classification terms that comply with reporting standards in Canada and the Mineral Reserves and the Mineral Resources estimates are made in accordance with NI 43-101. NI 43-101 is a rule developed by the Canadian Securities Administrators that establishes standards for all public disclosure an issuer makes of scientific and technical information concerning mineral projects. These standards differ from the requirements of the Securities and Exchange Commission (“SEC”) set the SEC's rules that are applicable to domestic United States reporting companies.   Consequently, Mineral Reserves and Mineral Resources information included in this presentation is not comparable to similar information that would generally be disclosed by domestic U.S. reporting companies subject to the reporting and disclosure requirements of the SEC Accordingly, information concerning mineral deposits set forth herein may not be comparable with information made public by companies that report in accordance with U.S. standards.

All material scientific and technical information in this presentation is derived from the Company’s independent feasibility study (the “Rook I FS Technical Report” or the “FS”) entitled “Arrow Deposit, Rook I Project, Saskatchewan, Nl 43-101 Technical Report on Feasibility Study dated March 10, 2021 filed under the Company’s profile on SEDAR+ at www.sedarplus.ca and on EDGAR at www.sec.gov. For details of the Rook I Project, including the key assumptions, parameters and methods used to estimate the Mineral Resources described in this Presentation, please refer to the Rook I FS Technical Report.

All scientific and technical information in this presentation has been reviewed and approved by Mr. Simon Allard, P.Eng, Vice President, Commercial, and Mr. Jason Craven, P.Geo., Vice President, Exploration for NexGen. Mr. Allard approved the scientific and technical information related to operational matters contained in this MD&A and Mr. Craven approved the scientific and technical information related to exploration matters. Each of Mr. Allard and Mr. Craven is a qualified person for the purposes of NI 43-101.

NexGen is in construction at Rook I.

It is the world’s largest uranium mine under construction1.

2 Based on calculation of Rook I potential production from the 2021 FS and Centre for International Economics modelling.

1 The current mine plan and economics remain those in the 2021 Feasibility Study

• In production Rook I estimated ~20% of global primary uranium supply.2
   
• More than 50% of Western supply.2
   
• 5 Rig drilling program at Patterson Corridor East (“PCE”).
   
• Most dominant land position in Saskatchewan’s southwestern Athabasca Basin.

NEXGEN | POWERING WHAT’S NEXT

NEXGEN | THE INVESTMENT CASE: CONTRACTING STRATEGY

Realized Weighted Volume Average Price For The First

3 Sales Commitments* Realized Table (Excludes Escalation):

Table based on initial sales commitments totaling 1 Mlbs U3O8 per annum over 5 years

*Rounded to the nearest dollar, includes any applicable discounts, excludes ancillary commissions, and associated costs of delivery. It is intended for illustrative pricing outcomes under 5 million pounds of committed volumes, based on various assumed spot price scenarios. These outcomes exclude the Company’s market-related pricing structure. Table does not include the August 2025 contract of an additional 5 million pounds. Refer to the December 4, 2024 Press Release for more information.

1 Statements regarding future cash flows, production, sales, uranium price, and operating costs of the Rook I Project are subject to the various risks and assumptions as outlined in the Company’s AIF, and those further described under the heading “Forward Looking Information” of this Presentation.

2 Refer to August 6, 2025 Press Release for more information.

- NexGen’s contracting strategy is designed to optimize shareholder returns:

• Volume-based contracts

• Market-related price mechanisms at the time of delivery

• Structure provides optimum leverage to future uranium prices

• Industry low OPEX provides protection in any pricing cycle

Applying a simple strategy which reflects the competent technical characteristics of the Arrow deposit:

- Maximize profitability (price) per lb sold by aligning sales with market demand.

Built by design.

Total sales commitments for 11.7 million lbs at market-related pricing, scheduled from commercial production.

Available for sale (of reserves) 227 million lbs at market related pricing, scheduled from commercial production.

Liquidity & Strategic Assets

Shares Issued

677 M

Options

47 M

Fully Diluted4

~724 M

Q1/26 Average Daily Trading Volume5

C$220 M

Supports a fully funded path to production with supportive shareholder alignment.

1 Approximate cash balance as per June 30st 2026

2 Based on IsoEnergy market capitalization as of September 25, 2026

3 On May 8, 2024 the Company entered into a binding term sheet with MMCap International Inc. SPC for purchase of 2,702,410 lb of natural uranium concentrate for an aggregate purchase price of US$250M based on the 5-day average UxC spot price. This transaction closed on May 28th 2024.

4 Inclusion of the new US$110M 2023 Debentures and the US$250M 2024. Debentures, converted at US$6.76 and US$10.73, respectively, would bring the number to fully diluted shares to 757,427,218. Assumes potential conversion of the US$110M 2023 Debentures converted at US$6.76 (~16M), and of the US$250M 2024 Debentures converted at US$10.73 (~23M)

5 Traded on the TSX, NYSE and ASX for Q1 2026

NEXGEN | GROWTH : CAP TABLE

Share Structure

C$970 M

Cash1

~30%

Iso Energy Ltd. Ownership (C$241M)2

PROJECT FINANCING OPTIONALITY:

Prepayments

Strategic Partners

Project & Corporate Debt and others

2.7 Mlbs

of U3O8 Strategic Uranium Inventory

Investor Relations

investors@nxe-energy.ca

Vancouver Office
Suite 3150, 1021 West Hastings Street

Vancouver BC V6E 0C3

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