Startup list · Global
Nuclear fission startups
Below are the top global nuclear fission startups, ranked by total funding. Together the 50 companies on this list have raised a combined $11B, and include 9 unicorns. The strongest hubs are United States, France, Denmark.
$11Bcombined funding · 50 companies
United Statestop hub
50companies shown
9unicorns
Ranked by total funding · Updated 2026-10-23 · Source: Dealroom
| # | Company | Founded | HQ | Funding |
|---|---|---|---|---|
| 1 |
 X
X-energyUnicorn
Delivering the next generation of carbon-free energy by reinventing nuclear power
|
2009 | Rockville, United States | $1.7B |
| 2 |
 T
TerraPowerUnicorn
Designs and develops advanced nuclear reactors focusing on a traveling wave reactor (TWR) concept, aiming for safe, affordable and sustainable nuclear energy
|
2008 | Bellevue, United States | $1.6B |
| 3 |
 V
Valar AtomicsUnicorn
Atomic energy company mass manufacturing nuclear fission reactors to synthesize low-cost hydrocarbons for global energy needs
|
2023 | El Segundo, United States | $1.5B |
| 4 |
 N
NewcleoUnicorn
Developing a new industrial standard of clean, safe and inexhaustible energy production from Nuclei
|
2021 | Lyon, France | $918M |
| 5 |
 K
Kairos PowerDealroom profile unavailable
Developing fluoride salt-cooled advanced nuclear fission reactors to deliver clean, firm, cost-competitive electricity
|
2016 | Alameda, United States | $643M |
| 6 |
 A
Antares
Military-grade microreactors offering resilient, autonomous energy solutions for remote and space applications
|
2023 | Los Angeles, United States | $632M |
| 7 |
 R
Radiant IndustriesUnicorn
Portable, failsafe nuclear microreactors for clean energy.
|
2019 | El Segundo, United States | $622M |
| 8 |
 N
NuScale PowerUnicorn
Develops modular and scalable small nuclear power systems
|
2007 | Corvallis, United States | $446M |
| 9 | A Atlas AtomicsUnicornDealroom profile unavailable Advanced heavy-water reactors using unenriched uranium fuel. | 2025 | Austin, United States | $400M |
| 10 |
 B
Blue EnergyFast growing
Prefabricated nuclear power plants built in shipyards for faster, cheaper deployment
|
2023 | Chevy Chase, United States | $235M |
| 11 |
 C
CORE-POWER
Clean energy technology for marine transport
|
2018 | London, United Kingdom | $219M |
| 12 |
 S
Standard NuclearUnicorn
Advanced TRISO nuclear fuel for next-generation reactors.
|
2025 | Oak Ridge, United States | $182M |
| 13 |
 L
Last EnergyFast growing
Small modular nuclear reactors with full lifecycle services
|
2020 | Austin, United States | $164M |
| 14 |
 N
NuCube EnergyFast growing
Solid-state fission reactors for industrial heat and power.
|
2023 | Idaho Falls, United States | $163M |
| 15 |
 J
Jimmy
Designs and operates atomic thermal generators to massively decarbonize industry
|
2020 | Paris, France | $142M |
| 16 |
 A
Aalo AtomicsFast growing
Creating abundant and dependable clean energy by advancing nuclear technology and attracting top talent from diverse industries
|
2023 | Austin, United States | $133M |
| 17 |
 T
Terrestrial EnergyUnicorn
Integral Molten Salt Reactor Technology
|
2013 | Charlotte, United States | $116M |
| 18 |
 C
CalogenaFast growing
Carbon-free heat generation using small modular nuclear reactors for efficient and safe energy solutions
|
2021 | Aix-en-Provence, France | $110M |
| 19 |
 S
Steady EnergyFast growing
Heat-only SMR for zero-carbon district heating
|
2023 | Rauma, Finland | $92M |
| 20 |
 B
Blykalla
Lead-cooled small modular reactors for baseload power
|
2013 | Stockholms kommun, Sweden | $83M |
| 21 |
 D
Deep Isolation
Deep Isolation solves the nuclear waste problem Our innovative and patented technology safely disposes of spent nuclear fuel
|
2016 | Berkeley, United States | $80M |
| 22 |
 T
The Nuclear Company
Fleet-scale nuclear power deployment using proven designs for cost-effective, reliable, and clean baseload energy
|
2023 | Lexington, United States | $71M |
| 23 |
 L
LIS TechnologiesFast growing
Powering the next generation of Small Modular Reactors (SMRs) with Laser Enrichment of UF₆
|
2023 | New York City, United States | $64M |
| 24 |
 C
Copenhagen Atomics
Providing cheap, green and abundant energy to drive growth and properity for mankind
|
2015 | Gladsaxe Municipality, Denmark | $61M |
| 25 |
 G
General MatterFast growing
Uranium enrichment and nuclear fuel production for energy independence
|
2024 | San Francisco, United States | $50M |
| 26 |
 T
Thorizon
Molten salt reactors converting nuclear waste into energy
|
2018 | Amsterdam, Netherlands | $47M |
| 27 |
 T
Transmutex
Recycles nuclear waste to create carbon-free nuclear energy
|
2019 | Vernier, Switzerland | $41M |
| 28 |
 S
StellariaFast growingDealroom profile unavailable
STELLARIA provides is a new nuclear energy solutions for centuries
|
2023 | Grenoble, France | $38M |
| 29 |
 D
Deep FissionFast growingDealroom profile unavailable
Revolutionizing energy with underground small nuclear reactors for safe, low-cost, and reliable power
|
2023 | Berkeley, United States | $34M |
| 30 |
 A
Alva EnergyFast growing
Turnkey project delivery for nuclear power uprates.
|
2024 | Cambridge, United States | $33M |
| 31 |
 T
Terra InnovatumDealroom profile unavailable
Micro modular reactors offering low-cost, reliable electricity with scalable, off-the-shelf components
|
2018 | Pittsburgh, United States | $32M |
| 32 |
 A
Apollo Atomics
Compact, factory-fabricated nuclear reactors for reliable baseload power
|
2025 | Cambridge, United States | $31M |
| 33 | B Blue Pivot Energy Technology Developing small modular nuclear reactors for next-generation clean energy generation. | 2025 | Huangpu, China | $28M |
| 34 |
 H
HEXANAFast growing
HEXANA develops innovative and modular fourth-generation nuclear SMR technology
|
2023 | Aix-en-Provence, France | $28M |
| 35 |
 S
SaltfossDealroom profile unavailable
Developing a nuclear power plant concept based on a molten salt reactor, to provide abundant, affordable, and sustainable energy
|
2015 | Copenhagen, Denmark | $25M |
| 36 |
 O
OtreraFast growingDealroom profile unavailable
A pioneer in new generation reactors for a sustainable energy future
|
2024 | Aix-en-Provence, France | $21M |
| 37 |
 C
Clean Core Thorium Energy
Innovative nuclear solutions maximizing safety, minimizing cost, and shrinking waste with thorium-driven power
|
2017 | Chicago, United States | $18M |
| 38 |
 U
Ultra Safe Nuclear
Manufacturer of micro-modular nuclear energy systems that deliver safe, clean, cost-effective power and heat to remote mines, industry and communities
|
2011 | Seattle, United States | $17M |
| 39 |
 G
Gen4 Energy
Gen4 Energy focuses on the manufacture, marketing, and distribution of technology mini reactors
|
2007 | Santa Fe, United States | $16M |
| 40 |
 M
Moltex Energy
Moltex Energy is developing a next generation nuclear reactor that can produce clean electricity
|
2014 | Saint John, Canada | $16M |
| 41 |
 C
CurioFast growingDealroom profile unavailable
Innovative nuclear technologies transforming waste into reliable, emissions-free electricity
|
2021 | Washington DC, United States | $15M |
| 42 |
 B
Blue Capsule TechnologyDealroom profile unavailable
Compact small modular reactors providing industrial-grade heat, high-temperature steam, and electricity with enhanced safety features
|
2022 | Aix-en-Provence, France | $13M |
| 43 |
 N
NuclearnFast growing
Artificial Intelligence for the Nuclear Industry
|
2021 | Phoenix, United States | $13M |
| 44 |
 P
Project OmegaFast growing
Recycling spent nuclear fuel into advanced power sources.
|
2025 | Newport, United States | $12M |
| 45 |
 N
NaareaDealroom profile unavailable
Carbon-free energy by reusing long-lived nuclear waste (Thorium)
|
2020 | Paris, France | $11M |
| 46 |
 M
Molten Salt SolutionsDealroom profile unavailable
Enriched lithium isotope production for advanced nuclear reactors
|
2018 | Santa Fe, United States | $10M |
| 47 |
 N
Nano Nuclear EnergyFast growingDealroom profile unavailable
Advanced technology-driven nuclear energy company seeking to become a commercially focused, diversified, and vertically integrated company across four business lines: (i) cutting edge portable microreactor technology, (ii) nuclear fuel fabrication, (iii) nuclear fuel transportation and (iv) nuclear industry consulting services
|
2022 | New York City, United States | $10M |
| 48 |
 A
Applied AtomicsFast growingDealroom profile unavailable
Co-located industrial nuclear plants using proven light-water SMR architectures
|
2025 | Anchorage, United States | $10M |
| 49 |
 A
AMPERAFast growing
Subcritical thorium microreactors for emission-free, scalable power.
|
2025 | Palm Beach Gardens, United States | $10M |
| 50 |
 H
HexiumFast growingDealroom profile unavailable
Advanced isotope enrichment technology for clean energy, nuclear medicine, and industrial applications with low capital costs
|
2023 | Austin, United States | $10M |
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