Slides
Page 1
The Athabasca Basin, Northern Saskatchewan Uranium Development & Exploration Corporate Update July 2025 #1 Non - Precious Mining Development Project in the World
Page 2
2 Cautionary Statements & References This presentation and the information contained herein is designed to help you understand management’s current views, and may not be appropriate for other purposes. This presentation contains third-party information, such as the uranium market, other issuers, provincial and federal infrastructure and regulations, etc., derived from third-party publications and reports which Denison believes are reliable but have not been independently verified by the Company. Certain information contained in this presentation constitutes “forward-looking information”, within the meaning of the United States Private Securities Litigation Reform Act of 1995 and similar Canadian legislation concerning the business, operations and financial performance and condition of Denison. Generally, these forward-looking statements can be identified by the use of forward-looking terminology such as “plans”, “expects”, “budget”, “scheduled”, “estimates”, “forecasts”, “intends”, “anticipates”, or “believes”, or the negatives and / or variations of such words and phrases, or state that certain actions, events or results “may”, “could”, “would”, “might” or “will be taken”, “occur”, “be achieved” or “has the potential to”. In particular, this presentation contains forward-looking information pertaining to the results of, and estimates, assumptions and projections provided in, the 2023 Phoenix feasibility study (“Phoenix FS”), the 2023 Gryphon PFS Update (“Gryphon PFS Update”) and the Waterbury PEA, including future development methods and plans, market prices, costs and capital expenditures; de-risking and project assessment activities, plans and objectives; assumptions regarding Denison’s ability to obtain all necessary regulatory approvals to commence development at Wheeler River; Denison’s percentage interest in its projects and assumed continuity of its agreements with its joint venture partners and other third parties; production and SABRE development outlook for McClean Lake; and estimates of uranium industry factors, including physical uranium supply and demand. Statements relating to "mineral resources" are deemed to be forward-looking information, as they involve the implied assessment, based on certain estimates and assumptions that the mineral resources described can be profitably produced in the future. Forward looking statements are based on the opinions and estimates of management as of the date such statements are made, and they are subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of Denison to be materially different from those expressed or implied by such forward-looking statements. Denison faces certain risks, including the proposed use of mining methods which are novel and untested in the Athabasca basin, the inability to permit or develop its projects as currently planned, the inability to secure sufficient financing to pursue its business objectives, the unpredictability of market prices, events that could materially increase costs, changes in the regulatory environment governing the project lands, and unanticipated claims against title and rights to the project. Denison believes that the expectations reflected in this forward-looking information are reasonable but there can be no assurance that such statements will prove to be accurate and may differ materially from those anticipated in this forward looking information. For a discussion in respect of risks and other factors that could influence forward-looking events, please refer to the “Risk Factors” in the Company’s Annual Information Form dated March 28, 2025 (“AIF”) available on SEDAR+ at www.sedarplus.ca and on EDGAR at www.sec.gov/edgar. These factors are not, and should not be construed as being, exhaustive. Readers should not place undue reliance on forward-looking statements. The forward-looking information contained in this presentation is expressly qualified by this cautionary statement. Any forward-looking information and the assumptions made with respect thereto speaks only to the effective date of this presentation. Denison does not undertake any obligation to publicly update or revise any forward-looking information after such date to conform such information to actual results or to changes in its expectations except as otherwise required by applicable legislation. Cautionary Note to United States Investors Concerning Estimates of Mineral Resources and Mineral Reserves: This presentation may use terms such as “measured”, “indicated” and/or “inferred” mineral resources and “proven” or “probable” mineral reserves, which are terms defined with reference to the guidelines set out in the Canadian Institute of Mining, Metallurgy and Petroleum (“CIM”) CIM Definition Standards on Mineral Resources and Mineral Reserves (“CIM Standards”). The Company’s descriptions of its projects may not be comparable to similar information made public by U.S. companies subject to the reporting and disclosure requirements under the United States federal securities laws and the rules and regulations thereunder. Qualified Persons The disclosure of a scientific or technical nature within this presentation, including the disclosure of mineral resources, mineral reserves, and the results of the Phoenix FS, Gryphon PFS Update and Waterbury PEA, was reviewed and approved by Chad Sorba, P.Geo, Vice President Technical Services & Project Evaluation, a Qualified Person in accordance with the requirements of NI 43-101. Technical Reports • For further details regarding the Wheeler River project, please refer to the Company’s press release dated June 26, 2023 announcing the results of the Phoenix FS and Gryphon PFS Update and the technical report titled "NI 43- 101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" with an effective date of June 23, 2023 ("Wheeler River Technical Report"). • For further details regarding the Waterbury Lake project, please refer to the Company’s press release dated November 17, 2020 and the technical report titled “Preliminary Economic Assessment for the Tthe Heldeth Túé (J Zone) Deposit, Waterbury Lake Property, Northern Saskatchewan, Canada” with an effective date of October 30, 2020 (“Waterbury PEA”). The PEA is a preliminary analysis of the potential viability of the Project’s mineral resources, and should not be considered the same as a Pre-Feasibility or Feasibility Study, as various factors are preliminary in nature. The PEA includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves, and there is no certainty that the preliminary economic assessment will be realized. Mineral resources are not mineral reserves and do not have demonstrated economic viability. Scheduled tonnes and grade do not represent an estimate of mineral reserves. For a description of the data verification, assay procedures and the quality assurance program and quality control measures applied by Denison, please see Denison’s AIF. A copy of the foregoing is available on Denison’s website and under its profile on SEDAR+ and on EDGAR.
Page 3
3 Key Investment Highlights(1): Advanced Athabasca Basin uranium developer with unique asset mix Three low-cost uranium development projects operated by Denison Phoenix, Gryphon, and THT/Waterbury all projected within UxC’s “First Tier” of global assets Phoenix combines lowest-cost mining method with Athabasca Basin high-grades Ranked #1 non-precious mining development project globally in 2025 by Mining Journal Intelligence Flagship ISR project with final federal Environmental Impact Statement accepted by CNSC Technical de-risking completed, with detailed design engineering and long-lead procurement in progress First production targeted by the first half of 2028 Interest in strategic regional asset with McClean Lake mill and mine Excess licensed milling capacity with approval for expanded tailings management facility Announced 2025 mining restart at McClean North deposit by Orano Canada High-potential exploration portfolio and interests in key mines / projects operated by “majors” Large exploration portfolio, including Moon Lake South and Johnston Lake properties Minority interests in Orano-Denison Midwest Joint Venture & Cameco-JCU’s Millennium project Strong balance sheet with ~CAD$310M in cash, physical uranium and investments(2) Denison’s financial and liquid assets on hand, relative to flagship development project initial capex (~$CAD400M) 3 is unrivaled and puts the company in an enviable position for project advancement Focused on the infrastructure-rich Eastern Athabasca Basin in Saskatchewan, Canada Nuclear renaissance: 30+ nations pledge to triple nuclear energy capacity by 2050 NOTES: (1) See supporting slides for details. (2) For additional details see financial statements and MD&A for the period ended March 31, 2025. (3) Based on Denison’s effective 95% ownership. #1
Page 4
4 PHOTO: Aerial view of Denison’s 22.5% owned McClean Lake mill facility NOTES: (1) Denison increased its effective interest in Wheeler River as part of the acquisition of 50% of JCU (Canada) Exploration Company, Limited. See Denison’s news release dated August 3, 2021. (2) See the Wheeler River Technical Report titled "NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" dated June 23, 2023. (3) See news release dated November 25, 2024 and Canadian Impact Assessment Registry (4) Refer to the Waterbury Lake Technical Report titled “Preliminary Economic Assessment for the Tthe Heldeth Túé (J Zone) Deposit, Waterbury Lake Property, Northern Saskatchewan, Canada” dated October 30, 2020. (5) See news release dated November 6, 2023. (6) See news release dated August 3, 2021. (7) Denison direct land position shown as of March 31, 2025; excludes the land positions held by JCU. Diversified Athabasca Basin asset base with superior development leverage 95% (1) effective interest in Flagship Wheeler River project Development-stage project Largest undeveloped uranium project in the infrastructure rich eastern Athabasca Basin 2023 Phoenix Feasibility Study(2) Final Environmental Impact Statement accepted by CNSC(3) 22.5% interest in Strategic McClean Lake Uranium Mill & Mines 11% of global uranium production processed through mill Mining restart activities using SABRE mining with production planned for mid 2025 Excess licensed milling capacity 70.55% interest in Emerging Waterbury Lake project PEA stage development project(4) Tthe Heldeth Túé (“THT”) deposit highlights potential for future development project pipeline Successful 2023 ISR field test(5) Participating interests in key development- stage assets operated by uranium “majors” Includes 22.5% in McClean Lake (Orano), 25.17% in Midwest (Orano), and an effective 15% in Millennium (Cameco) through 50% ownership of JCU(6) ~384,000 hectares of exploration ground(7)
Page 5
5 Denison’s development portfolio projects: Multiple assets amongst the lowest all-in cost assets of UxC’s First Tier NOTES: (1) Chart data, including “full costs” and UxC’s categorization of production cost “tiers”, have been derived from UxC’s estimates of worldwide production costs from the Uranium Production Cost Study dated September 2023. (2) For Phoenix and Gryphon, see the Wheeler River Technical Report titled "NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" dated June 23, 2023. (3) For THT/Waterbury, refer to the Waterbury Lake Technical Report titled “Preliminary Economic Assessment for the Tthe Heldeth Túé (THT) (J Zone) Deposit, Waterbury Lake Property, Northern Saskatchewan, Canada” dated October 30, 2020. $0 $10 $20 $30 $40 $50 $60 $70 All-in / Full Costs – USD$/lb U3O8 Sample of Global Production Costs – September 2023 (1)(2)(3) Planned and Producing Operations (with Mining Method) US$16.04 (2023) US$25.47 (2023) Denison/Canada KazakhstanCanada U.S.A. AfricaAustralia ISR ISR ISR UG OP ISR UG UG ISR UG UG OP ISR US$24.93 (2020) UxC’s “First Tier” “Second Tier” (up to ~US$48/lb U3O8) “Third/Fourth Tier” (up to ~US$92/lb U3O8) (includes lowest-cost projects with full costs up to ~US$33/lb U3O8) ISR UG UG OP
Page 6
6 McArthur River Mine Cigar Lake Mine McClean Lake Mill (Denison 22.5%) Rabbit Lake Mill Key Lake Mill Wheeler River (Denison 95%)(2) NOTES: (1) Denison direct land position shown as of March 31, 2025. (2) Reflects Denison’s effective interest, including a portion attributable to Denison’s 50% ownership in JCU (Canada) Exploration Company, Limited. See Denison’s news release dated August 3, 2021. Midwest (Denison 25.17%) Waterfound (Denison 24.68%)(2) Moon Lake South (Denison 75%) McClean Lake North (Denison 22.5%) Large land position in the infrastructure-rich eastern portion of the Athabasca Basin(1) Waterbury Lake (Denison 70.55%) All Season Highway / Haul Road Provincial Power Grid
Page 7
7 PHOTO: Packaged U3O8 yellowcake at Denison’s 22.5% owned McClean Lake mill. NOTES: (1) As of Mar. 31, 2025. For additional details see financial statements and MD&A for the period ended Mar. 31, 2025. Working capital is a non- IFRS financial measure and is calculated as the value of current assets less the value of current liabilities, excluding non- cash current liabilities. (2) See Denison’s news releases dated March 15, 2021, March 22, 2021, and April 1, 2021. (3) As of Mar. 31, 2025, for additional details see financial statements and MD&A for the period ended Mar. 31, 2025; includes investments in uranium equities and convertible debentures. (4) The company has no debt drawn as of Mar. 31, 2025; however, the company has a letters of credit facility in place that is used to secure reclamation letters of credit, as more fully described in the financial statements and MD&A. Robust Balance Sheet with ~CAD$310M (1) in cash, physical uranium and investments 2.2M lbs U3O8 in holdings of physical uranium at March 31, 2025 Market value ~CAD$204M (US$64.45/lb U3O8) +/- ~CAD$30M in change for every US$10/lb U3O8 move in spot price Acquired at average cost of USD$29.66/lb U3O8 Long-term holding expected to enhance access to future project financing for flagship Wheeler River Project(2) All material received and held in licenced North American storage facilities (Cameco + ConverDyn) CAD$84M in cash and cash equivalents(1) Working capital of CAD$74M(1) CAD$24M investments in uranium equities and convertibles(3) No Debt (4) Balance sheet position, relative to initial project capex for flagship development asset (Phoenix), is unrivaled among uranium development-stage peers
Page 8
8 95% owned flagship Wheeler River project(1)(2) Delivering Meaningful Production When the Market Needs It Two premier and viable development assets Phoenix – In-Situ Recovery (“ISR”) operation with on-site processing to finished U3O8 Gryphon – contributes additional production via conventional underground mining with assumed toll milling at 22.5% Denison owned McClean Lake mill ~16.5 years Aggregate operating Mine life(3) CAD$419M Estimated (100% basis) Initial CAPEX (Phoenix) Phoenix advancing to final investment decision Environmental Impact Statements accepted as final provincially and federally(4) CNSC Hearing dates set for late 2025(5) Total engineering ~75% complete(6) Rigorous multi-year technical de-risking program completed 2022 Feasibility Field Test successfully recovered uranium bearing solution Gryphon expected to be funded from internal cash flows Phoenix cash flow expected to fund Gryphon CAPEX Project benefits from existing or planned Denison-owned infrastructure 106.4M lbs U3O8 (combined, 100% basis) Proven & Probable Reserves 2-year Construction Planned construction period for Phoenix First half of 2028 Planned Production Start-up for Phoenix PHOTO: Installation of large- diameter commercial scale ISR test wells at Phoenix during 2021. LINKS: Wheeler River Project Page on Denison Website. NOTES: (1) Refer to the Wheeler River Technical Report titled "NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" dated June 23, 2023. (2) Denison increased its effective interest in Wheeler River as part of the acquisition of 50% of JCU (Canada) Exploration Company, Limited. See Denison’s news release dated August 3, 2021. (3) Reflects 10-year mine life estimated for Phoenix and 6.5-year mine life estimated for Gryphon. (4) See news release dated November 25, 2024 and Canadian Impact Assessment Registry (5) See news release dated February 27, 2025 and Canadian Impact Assessment Registry (6) As of Mar. 31, 2025. For additional details see financial statements and MD&A for the period ended Mar. 31, 2025.
Page 9
9 Phoenix In-Situ Recovery (“ISR”) Feasibility Study (2023): Reflects rigour of multi-year technical de-risking and delivers impressive economic results(1) 70.5M lbs U3O8 @ 11.4% U3O8 Measured & Indicated Mineral Resources (280,200 tonnes, 100% basis) One of the highest- grade undeveloped uranium deposits globally C$1.56B estimated Base-case post-tax NPV8% (100% basis)(3) C$419M estimated Initial CAPEX (100% basis) 90.0% estimated Base-case post-tax IRR(3) 3.7 to 1 impressive Base-case post-tax NPV to initial capital cost ratio Including… 56.3M lbs U3O8 @ 46.0% U3O8 M&I mineral resources for Zone A high-grade domain US$6.28 / lbs U3O8 average Cash Operating Costs (C$8.51/lb U3O8) US$16.04 / lbs U3O8 average All-in Cost(4) (C$21.73/lb U3O8) PHOTOS: Phoenix Feasibility Field Test (FFT) facilities during operations in 2022. NOTES: (1) See the Wheeler River Technical Report titled "NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" dated June 23, 2023. (2) www.mining- journal.com/research- reports/special- report/4204632/mining- journal-intelligence-project- pipeline-handbook-2024- epublication (3) NPV and IRR are calculated to the start of construction activities for the Phoenix operation and excludes $67.4 million in pre-FID expenditures. Post- tax NPV, IRR and payback period are based on the “adjusted Post-tax” scenario, which includes the benefit of entity level tax attributes which are expected to be available and used to reduce taxable income from the Phoenix operation. See Wheeler River Technical Report for details. (4) All-in cost is estimated on a pre-tax basis and includes all project operating costs, capital costs post-FID, and decommissioning costs divided by the estimated number of pounds U 3O8 to be produced. See Wheeler River Technical Report for details. #1 Non - Precious Mining Development Project in the World (2)
Page 10
10 Phoenix ISR Feasibility Study (2023)(1): Optimized production profile based on detailed ISR mine planning efforts NOTES: (1) Refer to the Wheeler River Technical Report titled "NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" dated June 23, 2023; (2) NPV and IRR are calculated to the start of construction activities for the Phoenix operation, and excludes $67.4 million in pre-FID expenditures; (3) Payback period is stated as number of months to payback from the start of uranium production; (4) Post-tax NPV is estimated to be $1.43 billion ($1.56 billion adjusted) in the base-case; (5) Post-tax payback period is estimated to be 11 months (10 months adjusted) in the Base-Case; (6) Post-tax IRR is estimated to be 82.3% (90.0% adjusted) in the Base-Case. Assumptions / Results(1) Base Case Selling price / lb U3O8 US$66-US$70 USD:CAD FX Rate 1.35 Pre-tax NPV8% (2)(4) (100%) $2.34 billion Change from 2018 PFS +150% Pre-tax payback period(3)(5) ~10 months Pre-tax IRR(2)(6) 106% Robust economics easily absorb cost-inflation + design changes First production targeted by the first half of 2028 Planned 2-year construction period 56.7 million lbs U3O8 in proven and probable reserves (219,000 tonnes at 11.7% U3O8)
Page 11
11 Figures 2023 Phoenix Feasibility Study Provides excellent basis for detailed engineering design efforts to support a future final investment decision NOTES: (1) Refer to the Wheeler River Technical Report titled "NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" dated June 23, 2023. Environmental disturbance limited by compact site Primary site facilities contained within area estimated to be less than 1 sq. km Robust mine planning process evaluation of production potential for individual well patterns: 74 extraction, 172 injection, and 22 monitoring wells
Page 12
12 2019/2020 ISR Field Tests(1) 35 small-diameter test, observation and re- charge wells 2 large-diameter commercial scale wells Pump and injection tests collecting critical hydrogeological data Demonstrated “ Proof of Concept” for use of ISR Specialized Core Leach Testing Leach testing indicative of in-situ conditions using intact core samples from Phoenix Results consistently produced uranium bearing solution head- grade levels significantly higher than grade used in the 2018 PFS (2) +97% recovery achieved during long-term test(3) Additional High- Grade uranium discovered at Phoenix (4) 22.0% eU3O8 over 8.6 metres in GWR-045 Located outside of the existing high-grade resource domain for Zone A and Phase 1 of the current mining plan 2021 field test of commercial-scale ISR test pattern(5) Achieved commercial- scale flow-rate used in the 2018 PFS Completed Athabasca Basin’s first “tracer test” showing hydraulic control, breakthrough times consistent with modelling, and ability to carry out “clean-up” PHOTOS (Left to Right): Small diameter ISR test wells installed at Phoenix in 2019; Specialized core- leach testing apparatus from the Saskatchewan Research Council (SRC); high-grade uranium core and scintillometer; monitoring of commercial scale ISR test wells at Phoenix in 2021. LINKS: 2021 Phoenix ISR Test Program on Vimeo NOTES: (1) See Denison’s news releases dated December 18, 2019, February 24, 2020, and June 4, 2020. (2) See Denison’s news releases dated February 19, 2020 and August 4, 2021. (3) See Denison’s news release dated December 8, 2022. (4) See Denison’s news release dated July 29, 2021. (5) See Denison’s news release dated October 28, 2021. Phoenix ISR De-Risking: Combining the world’s lowest-cost uranium mining method with one of the world’s highest-grade undeveloped uranium deposits
Page 13
13 Fully Permitted In-Situ Recovery Feasibility Field Test (FFT): Highly successful first-of-its-kind test in the Athabasca Basin(1, 2) PHOTO: Inside FFT coverall structure during commissioning – including view of commercial scale test wells, monitoring wells, and injection solution preparation module (left) and plan map of Phoenix FFT site (right). NOTES: (1) See Denison’s news release dated July 12, 2022. (2) See Denison’s news release dated August 8, 2022. (3) See Denison’s news release dated October 17, 2022. (4) See Denison’s news release dated December 12, 2022. (5) See Denison’s news release dated November 2, 2023. The Phoenix FFT was designed to validate and inform various Feasibility Study (FS) elements for use of In-Situ Recovery (ISR) mining, including production and remediation profiles, and is planned to occur in three phases. The first two phases supported the 2023 Phoenix FS. Leaching Completed successful injection of acidic solution and recovery of uranium bearing solution using a portion of the test pattern installed at Phoenix in 2021 (3). Neutralization Completed successful injection of mild alkaline solution to reverse the leaching process and return test area to protective conditions (4). Recovered Solution Management Completed compliance phase to separate recovered solution into mineralized precipitates (temporarily stored on site) and neutralized treated solution (injected into sub-surface) (5).
Page 14
14 Gryphon Underground (“UG”) Pre-Feasibility Study Update (2023): Provides Denison with additional source of low-cost production to reinvest Phoenix cash flows(1) 61.9M lbs U3O8 @ 1.7% U3O8 Indicated Mineral Resources (1,643,000 tonnes, 100% basis) Moderate grade allows low-cost conventional UG mining approach C $864M estimated Base-case after-tax NPV8% (100% basis)(2) C$737M estimated Initial CAPEX (100% basis) 37.6% estimated Base-case after-tax IRR(2) 2023 PFS Update Scope limited to cost update and minor schedule optimization Plus… 1.9M lbs U3O8 Inferred mineral resources (73,000 tonnes @ 1.2% U3O8, 100% basis) US$12.75 / lbs U3O8 average Cash Operating Costs (C$17.27/lb U3O8) US$25.47 / lbs U3O8 average All-in Cost(3) (C$34.50/lb U3O8) PHOTO: View inside the SX circuit at Denison’s 22.5% owned McClean Lake mill, which is assumed to toll mill production from the Gryphon UG operation NOTES: (1) See the Wheeler River Technical Report titled "NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" dated June 23, 2023. (2) NPV and IRR are calculated to the start of pre-production activities for the Gryphon operation. (3) All-in cost is estimated on a pre-tax basis and includes all project operating costs, capital costs post-FID, and decommissioning costs divided by the estimated number of pounds U 3O8 to be produced.
Page 15
15 Gryphon UG Pre-Feasibility Study Update (2023)(1): Capital and operating costs updated from 2018 PFS + minor scheduling optimizations Assumptions / Results(1) Base Case Selling price / lb U3O8 US$75 USD:CAD FX Rate 1.35 Pre-tax NPV8% (2)(4) (100%) $1.43 billion Change from 2018 PFS +148% Pre-tax payback period(3)(5) ~20 months Pre-tax IRR(2)(6) 41.4% Benefits from existing or planned Denison-owned infrastructure Payback period under 2-years for pre- and post- tax base-case scenarios 49.7 million lbs U3O8 in probable reserves (1,275,000 tonnes at 1.8% U3O8) NOTES: (1) Refer to the Wheeler River Technical Report titled "NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada" dated June 23, 2023; (2) NPV and IRR are calculated to the start of construction activities for the Gryphon operation, and excludes $56.5 million in pre-FID expenditures; (3) Payback period is stated as number of months to payback from the start of uranium production; (4) Post-tax NPV is estimated to be $864.2 million in the Base Case; (5) Post-tax payback period is estimated to be 23 months in the Base-Case; (6) Post-tax IRR is estimated to be 37.6% in the Base Case.
Page 16
16 22.5% Denison-owned McClean Lake Mill: Strategic asset uniquely positioned to support new sources of supply from JV owners ~10% of global uranium production (1) 2024 operating production of 16.9M lbs U 3O8 from Cigar Lake under toll milling agreement (3) 24M lbs U3O8 Licensed annual mill capacity(2) ~7M lbs U3O8 Excess licensed mill capacity Based on 2024 production from Cigar Lake 10-Year CNSC Operating License(2) Renewed in 2017 for operations up to June 30, 2027 Orano Canada Inc. French nuclear giant serves as site operator and is owner of 77.5% interest 750km north of Saskatoon (4) Accessible by road over all-weather highways and by air via Points North +50M lbs U3O8 Historic uranium production from mined McClean Lake deposits (JEB + Sue A, B, C, & E) (4) TMF Expansion Approved (2) CNSC approval obtained to increase tailings capacity PHOTO: Aerial view of Denison’s 22.5% owned McClean Lake mill facility LINKS: McClean Lake Project Page on Denison Website NOTES: (1) Per UxC’s Q12025 Uranium Market Outlook and Cameco’s management’s discussion and analysis dated February 20, 2025. (2) See Denison’s news release dated January 19, 2022. (3) Denison monetized its share of tolling revenues from the Cigar Lake toll milling agreement. See Denison’s news releases dated February 1, 2017 and February 13, 2017. Please also refer to Denison’s current Annual Information Form and Financial Statements and Management, Discussion and Analysis for additional details related to the toll milling agreement. (4) See Denison’s current Annual Information Form for additional details regarding the McClean Lake mill facility.
Page 17
17 22.5% Denison-owned McClean Lake Mine: SABRE mining method has potential to unlock value from unmined deposits close to mill SABRE Patented & Tested Successful 5-year test mining program for “Surface Access Borehole Resource Extraction” (SABRE) mining method SABRE is property of McClean Lake JV with patent issued in 2016 Produced ~1,500 tonnes of high-value ore from McClean Lake North in 2021 (1) 2025 Restart of Mining Orano Canada, operator or McClean Lake Mine is targeting production from McClean North in mid 2025(2) 17.8M lbs U3O8 Indicated Mineral Resources (3) (100% basis) Combined 374,900 tonnes @ 2.2% U3O8 7.6M lbs U3O8 Inferred Mineral Resources(3) (100% basis) Combined 510,900 tonnes @ 0.68% U3O8 2024 Activities Completion of the Pod 1 East SABRE pad, drilling and installation of four access holes for Pod 1 East and associated procurement (4) Orano Canada Inc. French nuclear giant serves as project operator and is owner of 77.5% interest 8.67% U3O8 over 13.5 metres Discovered “new” mineralization at McClean South (5) in 2021 + expanded footprint in 2022 (6) PHOTO: 2021 SABRE test mining program in action, with view of specialized mining pipes in inset photo. LINKS: McClean Lake Project Page on Denison Website NOTES: (1) See Denison’s news release dated November 3, 2021. (2) As reported by Orano Canada on January 24, 2024 Orano Canada SABRE announcement. (3) See Denison’s current AIF for additional details regarding the McClean Lake deposits and SABRE mining method. (4) See Denison's financial statements and MD&A for the year ended December 31, 2024 for details. (5) See Denison’s current AIF for additional details. (6) See Denison’s news release dated September 8, 2022.
Page 18
18 PHOTO: Isometric schematic of ISR wellfield and freeze wall at depth of the THT deposit on Waterbury Lake property. LINKS: Waterbury Lake Project Video on Vimeo Waterbury Project Page on Denison Website NOTES: (1) Refer to the Waterbury Lake Technical Report titled “Preliminary Economic Assessment for the Tthe Heldeth Túé (J Zone) Deposit, Waterbury Lake Property, Northern Saskatchewan, Canada” and dated October 30, 2020. (2) The PEA is a preliminary analysis of the potential viability of the Project's mineral resources and should not be considered the same as a Pre-Feasibility or Feasibility Study, as various factors are preliminary in nature. There is no certainty that the results from the PEA will be realized. Mineral resources are not mineral reserves and do not have demonstrated economic viability. (3) See Denison’s news release dated Nov. 6, 2023 70.55% owned Waterbury Lake project demonstrates potential for ISR to transform portfolio projects(1) ISR Mining Method Tthe Heldeth Túé (“THT”) deposit (formerly J Zone) designed as a low-cost In-Situ Recovery (“ISR”) operation with freeze wall design Uranium Bearing Solution (“UBS”) to be transported by truck to 22.5% Denison’s owned McClean Lake mill for toll processing Minimal site infrastructure Successful 2023 ISR field test (3) 6-year Mine Life CAD$112M estimated Initial CAPEX (100% basis) 9.7M lbs U3O8 projected Mine Production (100% basis) 12.8M lbs U3O8 @ 2.0% U3O8 (291,00 tonnes) in Indicated Mineral Resources estimated for THT (100% basis) NI 43-101 compliant Preliminary Economic Assessment (“PEA”) completed in 2020 (2) Partnership with consortium led by state- owned nuclear company Korea Hydro Nuclear Power (“KHNP”) Located within the boundaries of Treaty 10 in Nuhenéné / Athabasca Denesųłiné traditional territory and the homeland of the Métis 40,256 hectares of prospective ground over 13 claims
Page 19
19 Tthe Heldeth Túé (“THT”) ISR Operation: PEA (2020) shows potential for ISR to change uranium mining landscape in Canada(1) 1.6M lbs lbs U3O8 Average annual production over 6 years (100% basis) C$112M estimated Initial CAPEX (100% basis) US$12.23 / lbs U3O8 average Cash Operating Costs (C$16.27/lb U3O8) US$24.93 / lbs U3O8 average All-in Cost(2) (C$33.16/lb U3O8) C$265M estimated Pre-Tax NPV8% (100% basis) US$65/lb U3O8 selling price (see note 3, 4) 50.0% estimated Pre-Tax IRR US$65/lb U3O8 selling price (see note 3, 5) PHOTOS: Aerial rendering of surface facilities for the THT ISR operation NOTES: (1) Refer to the Waterbury Lake Technical Report titled “Preliminary Economic Assessment for the Tthe Heldeth Túé (J Zone) Deposit, Waterbury Lake Property, Northern Saskatchewan, Canada” dated October 30, 2020. (2) All-in cost is estimated on a pre-tax basis and includes all project operating costs and capital costs divided by the estimated number of finished pounds U 3O8 produced. (3) NPV and IRR are calculated based on assessed “high-case” uranium price, to the start of pre-production activities. (4) Post-tax NPV attributable to Denison’s then 66.90% interest is estimated to be between $72 million (base-case) and $109 million ($65/lb high-case). (5) Post-tax IRR attributable to Denison’s then 66.90% interest is estimated to be between 30.4% (base-case) and 38.9% ($65/lb high-case).
Page 20
20 25.17% Denison-owned Midwest Property: Two high-grade uranium deposits in close proximity to the McClean Lake mill Approved Environmental Impact Statement (“EIS”) Despite deferral of development decision in 2008, EIS approval efforts continued with assessment of open pit mining method and processing at McClean Lake CNSC approved final EIS in 2012 (1) 2024 ISR Field Test(3) Results suggest Midwest Main deposit possesses characteristics needed for ISR mining. ISR evaluation efforts advancing to PEA Orano Canada Inc. French nuclear giant serves as project operator and is owner of 74.83% interest Midwest Main deposit(2) 39.9M lbs U3O8 (453,000 tonnes @ 4.0% U 3O8) in Indicated Mineral Resources 11.5M lbs U3O8 (793,000 tonnes @ 0.66% U 3O8) in Inferred Mineral Resources Midwest “A” deposit(2) 10.8M lbs U3O8 (566,000 tonnes @ 0.87% U 3O8) in Indicated Mineral Resources 6.7M lbs U3O8 (53,000 tonnes @ 5.8% U 3O8) in Inferred Mineral Resources 25km from McClean Lake mill Via existing roads, and only 1km from the Points North airstrip PHOTO: Aerial view of Midwest Project. LINKS: Midwest Project Page on Denison Website NOTES: (1) See Denison’s current Annual Information Form for additional details regarding the Midwest project. (2) Refer to the Midwest Technical Report titled “Technical Report with an Updated Mineral Resource Estimate for the Midwest Property, Northern Saskatchewan, Canada” and dated March 26, 2018. Mineral resource figures shown on a 100% basis. (3) See Denison’s news release dated June 3, 2024.
Page 21
21 Environmental, Social, Governance & Indigenous (ESG+I) Fundamental considerations driving Denison’s operations PHOTO: Highlights of the Elders of Sakitawak’s market garden in Ile a la Crosse, a community-based initiative sponsored by Denison. LINKS: Denison’s ESG Report ERFN SPA Signing Video NOTES: (1) See news release dated December 2, 2021. (2) For more information: https://www.theglobeand mail.com/business/career s/management/board- games/article-canada- corporate-boards-ranking- 2024/ (3) See Denison’s news release dated March 15, 2021. (4) See news release dated September 27, 2023. (5) See news release dated July 11, 2024. (6) See news release dated October 20, 2022. (7) See MD&A for the period ended Dec. 31, 2022. (8) See Denison’s AIF for additional details. Comprehensive ESG Reporting Designed to address GRI, SASB, TCFD and other global disclosure frameworks Top 115 in Canada Leading Governance Practices & Disclosure Denison recognized by Globe & Mail “Board Games” as top uranium developer for corporate governance practices & disclosure in its assessment of leading companies and trusts included in Canada’s benchmark S&P/TSX Composite Index (2, 3) Board approved Indigenous Peoples Policy First-in-sector policy reflecting Denison’s commitment to take action towards advancing reconciliation with Indigenous peoples in Canada (1) Multiple Indigenous Agreements • Shared Prosperity Agreement with English River First Nation(4) • Mutual Benefits and Community Benefit Agreements with Kineepik Métis Local #9 and the Village of Pinehouse(5) • Participation/Funding and/or Exploration Agreements Ya’thi Néné Lands & Resources Office (6) and Métis Nation – Saskatchewan(7) Strong EHS&S Culture & Results One lost time injury across all operations and no significant environmental events for 2024 (8) Authentic Social Programs Denison’s community / social investment program targets community-based initiatives
Page 22
22 0 50 100 150 200 250 300 350 400 Existing Production Planned Production Secondary Supplies Uranium Demand Exiting extended period of excess suppy and inventory draw down Entering period of structural supply shortage Uranium Demand Base, High, Low The Uranium Investment Thesis: Growing supply deficit higher prices required to incent new supply Draw down of surplus inventories during period of production curtailments led transition to production-cost focused market First phase of supply response from incumbent producers insufficient to meet demand projections Market entering period of projected sustained structural supply shortage, with mine production deficit in 2024 estimated at ~20% of demand Geopolitical events highlighting importance of reliable / western sources of supply Demand yet to factor in significant small modular reactors (SMRs) growth, despite progress towards deployment for the late 2020s (2) Potentially significant increase in demand growth on the horizon with commitment of 30+ countries at COP29 to triple nuclear power capacity by 2050 NOTES: (1) Data in this slide has been derived from UxC’s Uranium Market Outlook dated Q1’2025, including supply & demand estimates and market balance figures. (2) OPG projects completion of SMR at Darlington by 2028 (LINK). Key Market Themes:Global Uranium Supply & Demand(1) (million pounds U3O8 - per UxC Q1’2025)
Page 23
23 Mineral Reserves & Resources as of December 31, 2024 Mineral Reserves (see Notes 1, 2, 3, 4, 8, 9) 100% Basis Denison Share(6) Project/Deposit Tonnes Grade % U3O8 Lbs U3O8 (,000) Lbs U3O8 (,000) McClean - Ore Stockpile (Proven) 90,000 0.37 700 200 Wheeler River - Phoenix (Proven) 6,300 24.5 3,400 3,200 Wheeler River - Phoenix (Probable) 212,700 11.4 53,300 50,600 Wheeler River - Gryphon (Probable) 1,257,000 1.8 49,700 47,200 Total Proven & Probable Reserves 1,566,000 107,100 101,200 Measured & Indicated Mineral Resources (see Notes 1, 5, 8, 9) 100% Basis Denison Share(6) Project/Deposit Tonnes Grade % U3O8 Lbs U3O8 (,000) Lbs U3O8 (,000) Wheeler River - Phoenix(5) (Measured) 64,200 21.8 30,900 29,400 Wheeler River - Phoenix(5) (Indicated) 216,000 8.3 39,700 37,700 Wheeler River - Gryphon(5) (Indicated) 1,643,000 1.7 61,900 58,800 McClean – Sue D (Indicated) 122,800 1.1 2,800 600 McClean – Sue F (Indicated) 47,800 2.6 2,800 600 McClean - McClean North (Indicated) 204,300 2.8 12,200 2,700 Midwest - Midwest Main (Indicated) 453,000 4.0 39,900 10,100 Midwest - Midwest A (Indicated) 566,000 0.87 10,800 2,700 Waterbury – THT (Indicated) 291,000 2.0 12,800 9,000 Total Measured & Indicated Resources 3,608,100 213,800 151,600 NOTES: (1) See AIF for details for further details, including cut-off grades used for mineral reserve and mineral resource estimates. CIM definitions were followed for classification of mineral reserves and mineral resources. Mineral resources are not mineral reserves and do not have demonstrated economic viability. (2) Mineral reserves are estimated at a cut-off grade of 0.5% U3O8 based on the ISR mining method, using a long-term uranium price of US$50/lb U3O8 and a CA$/US$ exchange rate of 1.33. The mineral reserves are based on a mine operating cost of $0.78/lb U3O8, process operating cost of $5.20/lb U3O8, and process recovery of 99%. The effective date of the mineral reserve estimate is June 23, 2023. A mine recovery of 80.6% has been applied to convert the mineral resources to mineral reserves. Recoverable U3O8 refers to ISR recoverable and does not account for process losses. (3) The effective date of the mineral reserves is September 1, 2018. Mineral reserves for the Gryphon deposit are estimated at a cut-off grade of 0.58% U3O8 based on longhole mining using a long-term uranium price of US$50/lb and a US$/CA$ exchange rate of 0.8. The mineral reserves are based on a mine operating cost of $150/t, mill operating cost of $275/t, G&A cost of $99/t, transportation cost of $50/t, milling recovery of 97%, and 7.25% fee for Saskatchewan royalties. Mineral reserves include for diluting material and mining losses.(4) Mineral reserves are stated at a processing plant feed reference point and include diluting material and mining losses. (5) Measured & Indicated mineral resources for Phoenix and Gryphon deposits are inclusive of mineral reserves. (6) As at December 31, 2024, pursuant to the terms of the agreements with its applicable joint venture partners, the Company had an effective 95.00% interest in the Wheeler River project, a 22.50% interest in the McClean Lake property; a 25.17% interest in the Midwest project; and a 70.32% interest in the Waterbury Lake property. (7) Denison’s share has been calculated as 50% of the product of JCU’s percentage interest in the applicable project multiplied by the estimated mineral resources on a 100% basis. (8) Numbers may not add due to rounding. (9) See AIF for all details of mineral reserves and mineral resources, including historical estimates. Inferred Mineral Resources (see Notes 1, 8, 9) 100% Basis Denison Share(6) Project/Deposit Tonnes Grade % U3O8 Lbs U3O8 (,000) Lbs U3O8 (,000) Wheeler River - Phoenix(5) 5,600 2.6 300 300 Wheeler River - Gryphon(5) 73,000 1.2 1,900 1,800 McClean - Sue D 24,200 0.39 200 0 McClean - Sue E 483,400 0.69 7,300 1,600 McClean - McClean North 3,300 0.79 100 0 Midwest - Midwest Main 793,000 0.66 11,500 2,900 Midwest - Midwest A 53,000 5.8 6,700 1,700 Waterbury - Huskie 268,000 0.96 5,700 4,000 Christie Lake 588,000 1.57 20,400 3,500 Total Inferred Resources 2,291,500 54,100 15,800 Historic Mineral Resources (see Notes 8, 9) 100% Basis Denison Share(7) Project/Deposit Tonnes Grade % U3O8 Lbs U3O8 (,000) Lbs U3O8 (,000) Millennium (Indicated) 1,442,600 2.39 75,900 11,400 Kiggavik (Indicated) 10,418,000 0.55 127,300 21,500 Tot. Historic Indicated Resources 11,860,600 203,200 32,900 Millennium (Inferred) 412,400 3.19 29,000 4,400 Kiggavik (Inferred) 733,000 0.33 5,400 900 Tot. Historic Inferred Resources 1,145,400 34,400 5,300
Page 24
24 Analyst Coverage(4) BMO (Alexander Pearce) Canaccord Genuity (Katie Lachapelle) Cantor Fitzgerald (Mike Kozak) CIBC (Anita Soni) Cormark (Nicolas Dion) Desjardins (Bryce Adams) Haywood (Marcus Giannini) National Bank (Mohamed Sidibé) Paradigm Capital (Gordon Lawson) Raymond James (Brian MacArthur) Roth (Joe Reagor) Scotiabank (Orest Wowkodaw) TD Cowen (Craig Hutchison) Shareholders(5) Capital Structure & Corporate Information Market Summary(1) Exchanges Shares Outstanding 896.2 M Share Purchase Warrants - Share Units 7.8 M Options 7.2 M Fully Diluted Shares 911.2 M DML (TSX) Market Cap @ C$2.49/share(2) CAD $2.2B Daily Trading Volume(3) 5.9M Shares DNN (NYSE American) Market Cap @ US$1.82/share(2) USD $1.6B Daily Trading Volume(3) 110M Shares LINKS: Website: www.denisonmines.com Twitter: @DenisonMinesCo Email: IR@denisonmines.com NOTES: (1) Share capital information as of May 12, 2025 (MD&A for the period ended Mar. 31, 2025). (2) Based on basic shares outstanding at May 12, 2025 (MD&A for the period ended Mar. 31, 2025) and DML/DNN share prices as of the end of June 2025. (3) Average daily trading volume over previous 3 months as of the end of June 2025. Canadian trading includes all Canadian exchanges. (4) As of June 30, 2025. (5) Shareholder information is estimated as of Dec. 31, 2024. Information is provided for indicative purposes only. Institutional holdings are estimated based on information available on Bloomberg. Insider holdings are estimated based on applicable filings and includes estimated holdings from entities entitled to appoint a nominee to the Board of Directors. Other holdings are determined as shares outstanding less those reported as institutional and insider holdings. Share ownership is subject to change. Management David Cates (President & CEO, Director) Elizabeth Sidle (VP Finance & CFO) Kevin Himbeault (VP Operations) Geoff Smith (VP Corp. Dev. & Commercial) Mary Jo Smith (VP Human Resources) Chad Sorba (VP Tech. Services & Project Eval.) Janna Switzer (VP Env., Sustainability & Regulatory) Amanda Willett (VP Legal & Corp. Sec.) David Bronkhorst (Technical Advisor) Board of Directors Jennifer Traub (Non-Executive Chair) David Cates (President & CEO, Director) Jinsu Baik (KHNP Nominee) Wes Carson Ken Hartwick David Neuburger Laurie Sterritt Patricia Volker Ron Hochstein (Board Advisor) 47% 7% 46% Institutional Insiders Other