How big is the nuclear & small reactors market?

installed capacity (operable reactors, net) (world): 405,667 MWe (443 reactors), 2026 — World Nuclear Association; electricity generated (world): 2,702 TWh (about 9% of world electricity), 2025 — World Nuclear Association.

Is the nuclear & small reactors market growing?

FORECAST: The World Nuclear Fuel Report 2025 Reference Scenario projects nuclear capacity rising from 372 GWe in 2024 to 746 GWe by 2040 (966 GWe Upper, 552 GWe Lower Scenario).

Who are the leading nuclear & small reactors companies?

Kazatomprom (KZ), Cameco (Canada), Orano (France), Urenco (United Kingdom), Rosatom (RU), China National Nuclear Corporation (CNNC) (China), Westinghouse Electric Company (United States), GE Vernova (GE Vernova Hitachi Nuclear Energy) (United States), and 10 more in the table above.

Which nuclear & small reactors companies are publicly traded?

Kazatomprom (KAP.L), Cameco (CCO.TO / CCJ), GE Vernova (GE Vernova Hitachi Nuclear Energy) (GEV), NuScale Power (SMR), X-energy (XE), Constellation Energy (CEG), Oklo (OKLO), Centrus Energy (LEU), BWX Technologies (BWXT).

Which Canadian companies are in nuclear & small reactors?

Cameco, Saskatoon; Ontario Power Generation, Oshawa, ON.

What is happening with nuclear & small reactors in Canada?

OPG's Darlington SMR-1 (GE Vernova Hitachi BWRX-300, 316 MWe gross) started construction on 26 June 2026, the first SMR in the G7. The CNSC licence to construct was granted on 4 April 2025. The total estimated cost for all four planned units is C$20.9 billion.

What are the main segments of the nuclear & small reactors market?

Small modular reactors and microreactors, Large new-build reactors, Restarts, uprates and life extensions, Uranium mining, Conversion, enrichment and HALEU, Fuel fabrication, components and services.

What are the risks in the nuclear & small reactors market?

First-of-a-kind SMR costs need to come down in series production (Darlington's first unit is budgeted at C$7.7B including shared infrastructure). If follow-on orders don't arrive, the economics may not close.

Nuclear & small reactors

SMRs, reactor restarts, new large builds and the uranium/enrichment fuel chain behind them

This market covers companies that design and build fission reactors, from small modular reactors (SMRs, generally 300 MWe or less and built from factory-made modules) to large 1,000+ MWe units. It also covers restarts of retired US plants and the fuel chain of uranium mining, conversion, enrichment (including HALEU) and fuel fabrication. The buyers are utilities, governments, and more and more industrial and data-centre power users who sign long-term power purchase agreements. Growth comes from government capacity targets, new financing such as loans, equity funds and tax credits, and rising demand for firm low-carbon power. At the same time, uranium and enrichment supply has to be built up to keep pace.

new market · sits inside NAICS 221113, 212290, 325180, 332410 · researched 2026-11-14

installed capacity (operable reactors, net) · world405,667

MWe (443 reactors) · 2026

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electricity generated · world2,702

TWh (about 9% of world electricity) · 2025

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capacity under construction · world89,673

MWe gross (82 reactors) · 2026

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investment · world75

USD billions ("around $75 billion", on course for 2025) · 2025

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Growth

Dated and sourced; forecasts are labelled as forecasts.

2025-09FORECAST: The World Nuclear Fuel Report 2025 Reference Scenario projects nuclear capacity rising from 372 GWe in 2024 to 746 GWe by 2040 (966 GWe Upper, 552 GWe Lower Scenario). ↗
2025-09FORECAST: Reactor uranium requirements of about 68,920 tU in 2025 are expected to rise to just over 150,000 tU in 2040 in the Reference Scenario. WNA says resources are sufficient but need further investment and timely decisions to bring them into production. ↗
2025-06IEA: capital flows to nuclear power have grown by 50% over the past five years and are on course to reach around $75 billion in 2025. ↗
2026-11POLICY TARGET: May 2025 US executive orders aim to raise US nuclear capacity from 100 GWe to 400 GWe by 2050, with 10 new large reactors under construction by 2030. In October 2025 the US government announced an $80 billion partnership with Westinghouse, Brookfield and Cameco to deploy AP1000 and AP300 reactors. ↗

Segments

Each linked segment has its own page with its companies.

Small modular reactors (SMRs) 8 — Reactors of 300 MWe or less (under 20 MWe for microreactors) built from factory modules. WNA counts over 100 designs: light-water, fast, high-temperature gas and molten salt.
Large nuclear reactors 5 — Gigawatt-class units such as AP1000, CANDU and Chinese Hualong designs. China accounts for most 2026 construction starts.
Reactor restarts & life extensions 2 — Returning retired US units (Palisades, Crane/TMI-1, Duane Arnold; 2,225 MWe) to service and raising output at existing plants.
Uranium mining 3 — About three-quarters of mined uranium comes from Kazakhstan, Canada and Namibia; ten companies produced over 90% (2022).
Uranium enrichment & HALEU 5 — Centrifuge enrichment by Rosatom, Urenco, CNNC and Orano (68,076 thousand SWU/yr in 2025), plus the new HALEU supply needed by more than half of SMR designs.
Nuclear fuel & components 4 — Fuel assemblies, reactor vessels and heavy components, engineering, and spent-fuel storage.

Leading companies in nuclear & small reactors

18 companies, with the scale each source states.

Company	Where	What they do	Scale
Kazatomprom KAP.L ↗	Astana, KZ since 1997	World's largest uranium miner (in-situ leach mines in Kazakhstan)	uranium production: 12,463 tonnes U (21% of world) (2024) ↗
Cameco CCO.TO / CCJ ↗	Saskatoon, Canada since 1988	Uranium miner (McArthur River/Key Lake, Cigar Lake), conversion and fuel services; 49% owner of Westinghouse	revenue: 3.482 CAD billions (2025) ↗
Orano ↗	Châtillon (Paris), France since 2001	Uranium mining, Georges Besse II enrichment plant, planned Project Ike enrichment plant at Oak Ridge, TN	enrichment capacity: 7,500 thousand SWU/yr (10,000 projected 2030) (2025) ↗
Urenco ↗	London, United Kingdom since 1971	Centrifuge enrichment in the UK, Germany, Netherlands and Eunice, New Mexico (expanding)	enrichment capacity: 17,300 thousand SWU/yr (2025) ↗
Rosatom ↗	Moscow, RU since 2007	Russian state nuclear group: reactor exports, the world's largest enrichment capacity, fuel, HALEU	enrichment capacity: 29,133 thousand SWU/yr (2025) ↗
China National Nuclear Corporation (CNNC) ↗	Beijing, China since 1955	Chinese state nuclear group: reactor design and construction, enrichment, uranium	revenue: 39.6 USD billions (2023) ↗
Westinghouse Electric Company ↗	Cranberry Township, PA, United States since 1999	AP1000 large reactor and AP300 SMR designer, fuel and services; partner in the US$80B US government deployment deal	employees: 11,000 employees (">11,000") (2026) ↗
GE Vernova (GE Vernova Hitachi Nuclear Energy) GEV ↗	Cambridge, MA, United States since 1892	Designer of the BWRX-300 SMR being built at Darlington (via the GE Hitachi JV, Wilmington NC)	revenue (whole company): 38.07 USD billions (2025) ↗
Ontario Power Generation ↗	Oshawa, ON, Canada since 1999	Owner/builder of Darlington New Nuclear (four BWRX-300 units); exploring large nuclear at Wesleyville	capital budget (4 SMR units): 20.9 CAD billions (2026) ↗
NuScale Power SMR ↗	Tigard, OR, United States since 2007	Light-water SMR module designer (NuScale Power Module)	revenue: 31.479 USD millions (operating loss US$689.6M) (2025) ↗
X-energy XE ↗	Rockville, MD, United States since 2009	Xe-100 pebble-bed high-temperature gas reactor and TRISO fuel; 4x80 MWe Seadrift, Texas project with Dow	proposed capacity (Seadrift): 320 MWe gross (4x80) (2026) ↗
TerraPower ↗	Bellevue, WA, United States since 2006	Natrium sodium fast reactor; Kemmerer 1, Wyoming construction permit issued March 2026	first-unit capacity: 345 MWe (2026) ↗
Holtec International ↗	Jupiter, FL, United States since 1986	Restarting Palisades (805 MWe, Michigan); SMR-300 design planned for Palisades; spent-fuel storage	restart capacity (Palisades): 805 MWe net (2026) ↗
Constellation Energy CEG ↗	Baltimore, MD, United States since 1999	Largest US nuclear fleet operator; restarting Crane Clean Energy Center (TMI-1, 819 MWe) under a 20-year Microsoft PPA	revenue: 25.533 USD billions (2025) ↗
Oklo OKLO ↗	Santa Clara, CA, United States since 2013	Fast-reactor microreactor/SMR developer and radioisotopes; pre-revenue	operating loss: -139.294 USD millions (2025) ↗
Centrus Energy LEU ↗	Bethesda, MD, United States since 1992	Enriched uranium supplier; producing HALEU from a demonstration cascade since October 2023	revenue: 448.7 USD millions (2025) ↗
BWX Technologies BWXT ↗	Lynchburg, VA, United States since 1867	Naval and commercial reactor components, heavy nuclear components and nuclear fuel; Canadian operations	revenue: 3.198 USD billions (2025) ↗
Korea Hydro & Nuclear Power ↗	Gyeongju, South Korea since 2001	South Korean reactor operator and APR-1400 builder (Shin-Hanul 4 construction start May 2026)	employees: 12,551 employees (2020) ↗

In Canada

2026-06OPG's Darlington SMR-1 (GE Vernova Hitachi BWRX-300, 316 MWe gross) started construction on 26 June 2026, the first SMR in the G7. The CNSC licence to construct was granted on 4 April 2025. The total estimated cost for all four planned units is C$20.9 billion. ↗
2026-07The Canada Growth Fund (up to C$2 billion) and the Building Ontario Fund (up to C$1 billion) committed equity to the Darlington New Nuclear Project. A refundable 15% Clean Electricity Investment Tax Credit covers nuclear equipment. ↗
2026-06Canada's Nuclear Energy Strategy (June 22, 2026) targets doubling the nuclear workforce by 2050. Nuclear supplies 13% of Canada's electricity, adds $22 billion a year to the economy and supports 90,000 direct and indirect jobs. ↗
2026-10Canada produced 24% of the world's mined uranium in 2024, second to Kazakhstan. Cameco's McArthur River/Key Lake (7,808 tU) and Cigar Lake (6,501 tU) were the world's two largest mines. ↗

What would have to be true

First-of-a-kind SMR costs need to come down in series production (Darlington's first unit is budgeted at C$7.7B including shared infrastructure). If follow-on orders don't arrive, the economics may not close.
HALEU, needed by more than half of SMR designs, is produced at scale only in Russia and China. Western supply depends on new enrichment capacity and government support.
Uranium resources are adequate to 2040 only if new mines are developed in time, and output is concentrated in a few countries and companies.
Licensing and execution slips can delay projects. Example: the Palisades restart paused fuel loading in 2026 and Holtec has not given a new restart date.

Quick answers

How big is the nuclear & small reactors market?: installed capacity (operable reactors, net) (world): 405,667 MWe (443 reactors), 2026 — World Nuclear Association; electricity generated (world): 2,702 TWh (about 9% of world electricity), 2025 — World Nuclear Association.
Is the nuclear & small reactors market growing?: FORECAST: The World Nuclear Fuel Report 2025 Reference Scenario projects nuclear capacity rising from 372 GWe in 2024 to 746 GWe by 2040 (966 GWe Upper, 552 GWe Lower Scenario).
Who are the leading nuclear & small reactors companies?: Kazatomprom (KZ), Cameco (Canada), Orano (France), Urenco (United Kingdom), Rosatom (RU), China National Nuclear Corporation (CNNC) (China), Westinghouse Electric Company (United States), GE Vernova (GE Vernova Hitachi Nuclear Energy) (United States), and 10 more in the table above.
Which nuclear & small reactors companies are publicly traded?: Kazatomprom (KAP.L), Cameco (CCO.TO / CCJ), GE Vernova (GE Vernova Hitachi Nuclear Energy) (GEV), NuScale Power (SMR), X-energy (XE), Constellation Energy (CEG), Oklo (OKLO), Centrus Energy (LEU), BWX Technologies (BWXT).
Which Canadian companies are in nuclear & small reactors?: Cameco, Saskatoon; Ontario Power Generation, Oshawa, ON.
What is happening with nuclear & small reactors in Canada?: OPG's Darlington SMR-1 (GE Vernova Hitachi BWRX-300, 316 MWe gross) started construction on 26 June 2026, the first SMR in the G7. The CNSC licence to construct was granted on 4 April 2025. The total estimated cost for all four planned units is C$20.9 billion.
What are the main segments of the nuclear & small reactors market?: Small modular reactors and microreactors, Large new-build reactors, Restarts, uprates and life extensions, Uranium mining, Conversion, enrichment and HALEU, Fuel fabrication, components and services.
What are the risks in the nuclear & small reactors market?: First-of-a-kind SMR costs need to come down in series production (Darlington's first unit is budgeted at C$7.7B including shared infrastructure). If follow-on orders don't arrive, the economics may not close.

Sources (12)

Nuclear Power in the World Today — World Nuclear Association
Small Modular Reactors — World Nuclear Association
Nuclear Power in Canada — World Nuclear Association
Nuclear Power in the USA — World Nuclear Association
World Uranium Mining Production — World Nuclear Association
Uranium Enrichment — World Nuclear Association
World Nuclear Fuel Report 2025 press statement — World Nuclear Association
Global energy investment set to rise to $3.3 trillion in 2025 — International Energy Agency
Darlington New Nuclear Project — Major Projects Office, Government of Canada
Government of Canada launches Nuclear Energy Strategy — Natural Resources Canada
XBRL company facts (NuScale, Oklo, Centrus, BWXT, Constellation) — US SEC
Company infoboxes (Cameco, Kazatomprom, Orano, Urenco, Rosatom, CNNC, Westinghouse, GE Vernova, GE Hitachi, NuScale, X-energy, TerraPower, Holtec, Oklo, Centrus, BWXT, Constellation, OPG, KHNP) — Wikipedia

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