Arrow: A Rapidly Growing Uranium Discovery | September 2015

Disclaimer Information Contained In This Presentation

This presentation is a summary description of NexGen Energy Ltd. (“NexGen” or the “Company”) and its business and does not purport to be complete. This presentation is not, and in no circumstances is it to be construed as, a prospectus, an advertisement, or a public offering of securities. No securities regulatory authority or similar authority has reviewed or in any way passed upon the document or the merits of the Company’s securities and any representation to the contrary is an offence.

Except where otherwise indicated, the information contained in this presentation has been prepared by NexGen and there is no representation or warranty by NexGen or any other person as to the accuracy or completeness of the information set forth herein. This presentation includes information on adjacent properties that was obtained from various publicly available sources referred to herein and the accuracy and completeness of such information has not been verified by NexGen. Except as otherwise stated, information included in this presentation is given as of the date hereof. Neither the delivery of this presentation nor any sale made under the terms described herein shall imply that the information herein is correct as of any date after the date hereof.

All dollar amounts referenced herein, unless otherwise indicated, are expressed in Canadian dollars.

Cautionary Note Regarding Forward-looking Information

Statements contained in this presentation that are not current or historical factual statements may constitute “forward-looking information” within the meaning of applicable securities laws including statements with respect to the properties, a concurrent financing, our plans for exploration and development of our properties and our financial condition, operations and prospects. The forward-looking information reflects current expectations regarding future results, performance or achievements and speaks only as of the date of this presentation. When used in this presentation, forward-looking information can be identified by such words as “may”, “will”, “expect”, “believe”, “plan”, “project”, “anticipate”, “intend”, “estimate” and other similar terminology. Such forward-looking information involves known and unknown risks, uncertainties and other factors that may cause the actual results, performance or achievements of the Company to be materially different from any future results, performance or achievements expressed in or implied by such information. Such risks,

uncertainties and other factors include, but are not limited in any manner to those risks set forth in this presentation under the heading “Risk Factors”, including, the risk that no mineralization will be identified on the Radio and Rook I properties; the Company’s dependence on third party financing; the Company’s limited operating history; risks inherent in exploration activities; environmental and safety risks including increased regulatory burdens; unexpected geological or hydrological conditions; a possible deterioration in political support for nuclear energy; changes in government regulations and policies, including trade laws and policies; demand for nuclear power; failure to obtain necessary permits and approvals from government authorities; weather and other natural phenomena; and other exploration, development, operating, financial market and regulatory risks. The foregoing list of factors is not exhaustive.

The forward-looking information contained in this presentation requires management to make certain assumptions including with respect to the financing and its ability to successfully develop its properties. Although management of the Company believes that the assumptions underlying, and the expectations reflected in, the forward-looking information are reasonable, significant risks and uncertainties are involved in such information. Management can give no assurances that its assumptions, estimates and expectations will prove to have been correct. Forward-looking information should not be read as guarantees of future performance or results, and will not necessarily be accurate indications of whether or not or the times at or by which such performance or results will be achieved. Many factors that are beyond the Company’s control could cause actual results to differ materially from the results discussed in the forward-looking statements.

The technical information in this presentation has been prepared in accordance with the Canadian regulatory requirements set out in National Instrument 43-101 and reviewed on behalf of NexGen Energy Ltd., by Garrett Ainsworth, P.Geo., Vice President – Exploration & Development, a qualified person.

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3 Uranium Market (Demand) A Story of Stable Demand Growth and Uncertain Supply

Nuclear Electricity Growth • Nuclear energy fuels 11% of the global electricity needs • 930 GW needed by 2050 to support existing global decarbonisation mandates • Equates to a 2.3 times increase in nuclear energy demand in just 35 years

Uranium Demand • Average demand growth estimated at ~4% per year to 2024

Source: International Energy Agency (2015), World Nuclear Association (2015)

4 Uranium Market (Demand) Investment and Reactor Builds

• Currently 437 nuclear reactors in operation globally • As of April 2015, 65 nuclear reactors are under construction

• China: 26 currently, 23 under construction, 187 in planning/proposal phase • China Nuclear Power Corp. “looking to invest in Canada in the near future” (Dec. 2014)

• Another 496 reactors are in the planning/proposal phase 1.) Graph: International Energy Agency (2015) 2.) World Nuclear Association (2015)

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5 Uranium Market (Supply) Lack of Economic Deposits

• In 2014 world uranium

consumption was 155Mlbs while mine supply accounted for 147Mlbs

• +20Mlbs from HEU agreement (now over)

• Estimated supply gap of

nearly 100Mlbs per year by 2030

• 11 of top 15 uranium

mines are in unstable jurisdictions (Russia, Kazakhstan, Niger)

End of HEU agreement in 2013 removed the equivalent of McArthur River’s annual production from supply

1.) World Nuclear Association (2015) 2.) World Nuclear Association estimate of 97,450tU demand and 53,000 tU supply in 2030

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6 The Athabasca Basin The Source of Future Supply

1.) World Nuclear Association (2015) 2.) Cameco Corp. 3.) Based on US$45/lb U & US$1,300/oz Au

Remember: 1.00% U3O8 = 23.50 g/t gold!

• Global average

resource grades ~0.10% U3O8

• Athabasca Basin mines produce at over 100X global average resource grade

• McArthur River produced 19Mlbs at average grade of 14.87% U3O8 in 2014

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7 Project Overview Focus: High-tonnage, high-grade, technically superior assets in shallow sections of the Athabasca Basin

Portfolio Characteristics

• Straddles the edge and inside of the Athabasca Basin

• Enables NexGen to find basement-hosted, unconformity-hosted and sandstone-

hosted mineralization

• Hosts the land-based Arrow discovery

8 Arrow Discovery Rook I Project Location & Conductor Corridors

• Most dominant land position in the Southwest Athabasca Basin

• Arrow discovered Feb 2014 with 1st drill hole and drilling at +90% hit rate

• Land-based discovery

located straddling and inside the Athabasca Basin boundary

• Basement-hosted high-grade mineralization that grows all directions and at depth

Rook I hosts all the known uranium bearing conductor corridors in the region

9 Successful Drilling at Arrow +90% of Drill Holes Intersected High-grade Uranium Mineralization

NexGen’s Drilling Methodology:

1. Wide step-outs 2. Angled Holes: 90% of

holes drilled are angled 3. Efficient capital

allocation: 8:1 $ in the ground to $ to G&A

4. Incredible hit rate: +90% of holes hit mineralization

Results: Current Area of Mineralization:

• Length x width 645 m x 215 m

• Depth 100 m to 920 m

10 Arrow: A2 & A3 Shears Plan view of Arrow

11 A2: Continues to Expand Recently tripled strike length with aggressive step outs

12 A3: New High-grade Shear Developing Aggressive 50, 100 and 210m step outs from -44b ALL hit mineralization

13 Arrow: A2 & A3 Cross-Section • Both A2 and A3

Zones remain open in every direction

• NE extent of Arrow opened up with AR-15-40b (11.5m at 0.99% U3O8)

A2 Dimensions:

• 300m strike length • 340m vertical extent • 11-48.3m true width

A3 Dimensions:

• 295m strike length • 420m vertical extent • 30-78.6m true width

2 High-grade shear zones now identified at Arrow

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Athabasca Basin Setting

15 The Eagle Point Analogy Eagle Point is an underground mine operated by Cameco

- Eagle Point current mineral reserves: 15.2Mlbs at 0.61% U3O8. 2014 annual production of 4.2Mlbs

- Underground mine using longhole stoping in the competent basement rock

- Eagle Point deposits are located on the eastern edge of the Athabasca Basin, and are part of the Rabbit Lake Uranium district which also includes the Rabbit Lake and Collins Bay deposits.

- Rabbit Lake District produced +198Mlbs of uranium concentrates since production began in 1975

1.) Cameco Corp.

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16 Dravite Breccia – McArthur River & Arrow

1.) Cameco Corp.

Arrow: AR-14-15 422.25m Dravite associated (or proximal) to mineralization

McArthur River: Dravite-Chlorite-filled Breccias associated with high-grade mineralization

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17 Bow: New Discovery 3.7km NE of Arrow

BO-15-10: • 9.5m @ 0.20%

U3O8 including 1m @ 1.44% U3O8

• 66m step-out to

east of drill hole BO-15-02

• Now identified a 350m strike length of anomalous radioactivity at Bow

• Currently drilling land target to NE of Bow

18 Bow Discovery Drill Locations

• BO-15-10, -02 drilled into a gravity low anomaly with coincident VTEM conductor and radon in lake water anomaly with peak reading of 36.0pCi/L

19 BO-15-10: Visible Pitchblende

20 Patterson Conductor Corridor Multiple targets along 7kms of conductor corridor

21 On Land Gravity Low: Summer 2015

22 Summer Drill Targeting – Bow, Derkson • Multiple

high priority targets based on the same geophysical signature as Arrow

• Land-based

• Regional summer drill program to further define Bow and drill first holes in Derkson conductor corridor

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Eastern Athabasca Basin Portfolio

High Quality Portfolio: 1. Radio: located directly

adjacent to and long strike of Roughrider, Rio Tinto acquired for $654M in February 2012.

2. Thorburn Lake: 9 of 15 drill holes have intersected uranium mineralization.

3. Madison and 2Z Lake: contain shallow (<100m thick) sandstone-hosted uranium mineralization, and is along strike from U-mineralized conductors. Represent good potential for discovery of new basement-hosted uranium deposits.

24 NexGen Summary • Arrow, a world-class uranium discovery that keeps growing

• +90% of holes hitting mineralization

• Aggressive and deliberate drilling methodology

• Area of mineralization 645 m x 215 m, vertical extent commencing from 100 m down to 920 m

• Two high-grade shear zones; A2 & A3 identified with broad intercepts of high-grade uranium encountered

• Arrow remains open in every direction and at depth. Recently drilled 50, 100 and 210m step outs to southwest of AR-15-44b and all hit mineralization

• A brand new discovery made 3.7km northeast of Arrow called “Bow”

• Well funded with ~C$30M cash on hand

• Aggressive 5 rig, expanded 30,000m summer 2015 program underway

25 Arrow: Perspective on Size The Empire State Building next to Arrow

Empire State Building Total height: 443m (~54% of Arrow’s height)

Arrow Total height: 820m (starting from 100m of surface)

Image made via Leapfrog software using latest drill data from Arrow zone. No NI 43-101 has been published for the Arrow zone to date.

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APPENDICIES

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AR-15-44b - A record hole at Arrow

28 NexGen Outperforming Peers

* 3-month share price returns in Canadian Dollars as of August 11, 2015

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Executive, Board & Technical Team

Executive Leigh Curyer Chief Executive Officer

Garrett Ainsworth VP Exploration & Development

Grace Marosits Chief Financial Officer

Travis McPherson Corporate Development Manager

Board Chris McFadden Chairman

Richard Patricio Trevor Thiele Craig Parry Gerry Feldman James Currie Directors

Technical Team Garrett Ainsworth VP Exploration & Development

Adam Engdahl Project Manager - Saskatchewan

Galen McNamara Project Manager - Geology

Technical Advisory Andrew Browne former VP Exploration & Development

Craig Parry Director

Strong team with a successful track record in uranium exploration and

development.

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Capital Structure Shares Issued & Outstanding 253,972,116

Warrants ($0.45 - $0.65) 20,532,728

Options ($0.30 - $0.46) 21,399,446

Fully Diluted 295,904,290

Cash ~C$30M

Ownership Management/Directors Tigers Realm Minerals & Associates Mega Uranium

~6%

~14% ~9%

1.) As of August 24, 2015 2.) As of June 30, 2015

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31 The Éléonore Example Putting Arrow’s depth extent in context

Goldcorp’s Newest Mine:

Mine Plan • 1,145m depth (starting at 55m

from surface)

Average Gold Grade • 6.34g/t Au (equivalent to 0.27%

U3O8)

Development Capex • US$1.8 billion

1.) Goldcorp 2.) Based on US$45/lb U & US$1,300/oz Au

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32 Arrow: No Freezing • Arrow is basement-hosted which means NO freezing would be required

• Unlike McArthur River and Cigar Lake which have 600 and 480m of

sandstone on top of the ore bodies, respectively - Arrow only has 10-20m of sandstone within 80m of surface

• Cigar Lake is world-class in size and grade, but faces significant challenges due to fact ore is sandstone-hosted and requires futuristic mining methods

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Analyst Coverage

Mike Kozak - Cormark Securities Inc.

(416) 943 6749 BUY C$1.75

Rob Chang – Cantor Fitzgerald Canada

(416) 849 5008 TOP PICK N/A

David Sadowski – Raymond James Ltd.

(604) 659 8255 BUY C$1.80

David Talbot – Dundee Capital Markets

(416) 350 3082 BUY N/A

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Contact

Travis McPherson Corporate Development

C: +1 604.816.2686

T: +1 604.428.4112

tmcpherson@nexgenenergy.ca