What are the top advanced nuclear startups by revenue today?

The ranking of top startups in the Advanced Nuclear Market by revenue

Below is a table ranking the startups of this market by their current revenue scale. You can find our methodology at the end of this page.

If you want a deeper understanding of the market and its current dynamics, get our report on the advanced nuclear market.

Why is everyone suddenly interested in advanced nuclear startups?

Advanced nuclear startups are getting serious attention because technology companies now need enormous amounts of reliable electricity, and several have started backing actual reactor projects.

Google helped change the market in October 2024 when it signed an agreement with Kairos Power for up to 500 MWe of nuclear capacity by 2035. In January 2026, Meta announced an agreement with TerraPower covering up to eight Natrium reactor plants, potentially delivering 2.8 GW of baseload electricity. Amazon has also supported X-energy's reactor-development plans, including a proposed initial four-reactor project with Energy Northwest.

Developers that previously depended heavily on government programs and investors are now negotiating directly with companies facing long-term electricity shortages. It's a pretty significant change in who is willing to support these projects.

There has also been progress on the regulatory side. In March 2026, the U.S. Nuclear Regulatory Commission issued TerraPower a construction permit for its first Natrium plant in Wyoming, the first construction permit for a commercial non-light-water power reactor in the United States.

But electricity deliveries under these newer agreements are generally expected around 2030 or later.

Which advanced nuclear startups make the most revenue today?

X-energy is currently the largest advanced nuclear startup by revenue in our ranking, followed by newcleo, Standard Nuclear, Oklo, ASP Isotopes, NuScale Power, NANO Nuclear Energy and Steady Energy.

The numbers show how young this market still is. X-energy reported $90M in services revenue during the first six months of 2026. Newcleo generated €32.8M from products and services in FY2025, while Standard Nuclear recorded $5.33M in first-half 2026 sales.

After those three companies, the figures fall sharply. Oklo reported $1.21M, ASP Isotopes generated $800K from its nuclear-fuels segment, and NuScale Power recorded $640K during the first half of 2026. NANO Nuclear reported $214K for its latest fiscal quarter, while Steady Energy's latest useful annual turnover figure was €270K in FY2025.

These figures cover different reporting periods and business activities, which we preserve rather than turning them into hypothetical annual sales. The ranking reflects the strongest relevant commercial evidence available for each startup, including the recency of its revenue.

Rank	Advanced nuclear startup	Revenue	Reporting period and metric
1	X-energy	$90M	H1 2026 services revenue
2	newcleo	€32.8M	FY2025 products and services revenue
3	Standard Nuclear	$5.33M	H1 2026 revenue
4	Oklo	$1.21M	H1 2026 revenue
5	ASP Isotopes	$800K	H1 2026 nuclear-fuels segment revenue
6	NuScale Power	$640K	H1 2026 revenue
7	NANO Nuclear Energy	$214K	Q3 FY2026 quarterly revenue
8	Steady Energy	€270K	FY2025 annual net turnover; H1 2026 turnover was zero

How much revenue does X-energy make?

X-energy made $90M in services revenue during the first half of 2026, putting the advanced nuclear startup comfortably ahead of every other company in our revenue ranking.

The company's August 2026 financial results show that services revenue increased from $34.0M in the first half of 2025 to $90.0M in the first half of 2026, a 165% increase. Second-quarter revenue alone reached $50.1M, compared with $16.9M a year earlier.

The growth is unusually strong for a company still developing its first commercial Xe-100 reactor deployments. X-energy already earns money from engineering and development services while preparing larger reactor and fuel projects involving customers such as Dow and Amazon.

X-energy also recorded approximately $8M in grant income during the first half of 2026. We keep that separate from services revenue.

Its growth has come with substantial costs, though. Direct expenses reached approximately $152M in the first half, compared with $64.9M a year earlier.

Is newcleo already making serious money from nuclear technology?

Newcleo is already an established revenue-generating nuclear technology business, with €32.8M in FY2025 products and services revenue, placing it second in the advanced nuclear startup ranking.

The company's latest annual figure was actually lower than the €46.7M recorded in 2024. The subsequent recovery is more encouraging.

In the first half of 2026, newcleo generated €19.429M, compared with €13.347M a year earlier. Revenue grew approximately 46%, driven by equipment manufacturing, installation, spare parts and consultancy services.

Newcleo is developing lead-cooled fast reactors and advanced nuclear fuel capabilities, but most of its current revenue comes from existing industrial work. It already has paying customers, even though its reactor technology has not reached commercial deployment.

The financial results also show the cost of developing that technology. Newcleo reported an approximately €82M net loss in the first half of 2026, against €19.429M in revenue.

Newcleo entered public markets in September 2026, making it eligible under our startup definition.

Is Standard Nuclear becoming a real nuclear fuel supplier?

Standard Nuclear is already selling specialized nuclear fuel products and services, and its revenue is growing extremely quickly. The company ranks third among advanced nuclear startups with $5.33M in first-half 2026 sales.

According to its August 2026 financial results, revenue increased from $930,865 in the first half of 2025 to $5.33M in the first half of 2026. That's growth of approximately 473%.

The most interesting part is the change in the company's revenue mix. In the first half of 2025, Standard Nuclear's reported revenue came from services. A year later, it had generated approximately $3.1M in product revenue, alongside $2.23M from services.

The company is developing manufacturing capabilities for TRISO fuel, used in several advanced reactor designs. It has also announced fuel supply agreements involving developers such as Radiant Industries and Antares Nuclear.

Standard Nuclear's reported backlog reached $576.9M after including an August 2026 fuel supply agreement. That amount covers future contractual activity and remains separate from the $5.33M already recognized.

Its first-half cost of revenue was $6.56M, resulting in a gross loss of approximately $1.23M. The demand is real. Whether larger production volumes will generate attractive margins is still an open question.

How much money is Oklo making from nuclear energy?

Oklo reported $1.21M in revenue during the first half of 2026, placing it fourth among advanced nuclear startups. The company has started earning money, although its Aurora reactors have yet to generate commercial electricity revenue.

The SEC filing published in August 2026 shows that all $1.21M was recognized during the second quarter. In the equivalent six months of 2025, Oklo recorded no revenue.

It's a clear change in its financial profile. The sales, however, remain tiny compared with operating expenditure.

Oklo spent approximately $66.5M on R&D and $58.1M on general and administrative expenses during the first half of 2026. Its operating loss reached approximately $124M.

The company is pursuing fast reactors, nuclear fuel capabilities and electricity supply agreements. Meta's January 2026 nuclear procurement announcement also included an arrangement involving Oklo.

Those future projects could make the business far larger, but its present financial position is still driven overwhelmingly by development spending. The first $1.21M of revenue is a useful milestone, though it tells us very little about what commercial power generation might eventually earn.

How much revenue does ASP Isotopes make from nuclear fuel?

ASP Isotopes generated $800K from its nuclear-fuels segment in the first half of 2026, giving it fifth place in the advanced nuclear startup revenue ranking.

The company's total revenue was substantially higher at $9.303M, according to its August 2026 SEC filing. Most of that money came from other activities, including specialist isotopes and related services.

ASP Isotopes works across several industries, so counting its entire revenue as advanced nuclear fuel sales would exaggerate the scale of that particular business. Its nuclear-fuels segment accounted for approximately 8.6% of consolidated revenue during the first six months of 2026.

The nuclear-fuels business also reported a loss before allocation to noncontrolling interests of approximately $20M over the same period. Its revenue is still extremely small compared with the amount being invested.

ASP Isotopes is developing enrichment and isotope-separation technologies that could become useful for advanced nuclear fuel supply.

Why has NuScale Power's revenue fallen so much?

NuScale Power's revenue fell approximately 97% year over year in the first half of 2026, leaving the small modular reactor developer with just $640K in recognized sales and sixth place in our ranking.

According to the company's second-quarter 2026 financial statements, revenue declined from $21.429M in the first six months of 2025 to $640K in the equivalent 2026 period.

Second-quarter revenue was only $75K, compared with $8.054M a year earlier.

The main reason is the changing pattern of engineering work and associated revenue recognition. Earlier contracts supported much higher sales, but that work did not continue at the same level.

NuScale remains one of the best-known developers of small modular reactor technology and has achieved important U.S. regulatory milestones. Its design approvals, however, have yet to translate into a consistent stream of large commercial orders and revenue.

Is NANO Nuclear Energy already selling microreactors?

NANO Nuclear Energy is generating revenue from nuclear logistics, but commercial microreactor sales have not started. The company ranks seventh with $214K in revenue for its third fiscal quarter of 2026.

The money came from Secured Transportation Systems, a specialized nuclear transportation and logistics business acquired in May 2026.

That acquisition gave NANO Nuclear an existing commercial activity alongside its reactor-development programs. It also brought experience in handling and transporting radioactive materials, which could support the company's broader nuclear operations.

Meanwhile, NANO Nuclear is developing the KRONOS MMR microreactor platform. In August 2026, the company reported that the U.S. Nuclear Regulatory Commission had accepted its construction permit application for a project at the University of Illinois.

Is Steady Energy making money from nuclear district heating?

Steady Energy has generated some commercial turnover, but its latest results show that revenue remains extremely limited. The Finnish district-heating reactor startup ranks eighth, with €270K in FY2025 net turnover.

According to its official financial figures, turnover increased from €175K in 2024 to €270K in 2025, a gain of approximately 54%.

However, Steady Energy reported zero net turnover in the first half of 2026, compared with €270K during the equivalent period a year earlier.

The company is developing compact nuclear reactors designed to supply heat to district-heating networks. It's a different business from selling electricity to data centers or national grids.

Steady Energy's first-half 2026 EBITDA loss was approximately €11.7M, while cash and bank balances stood at approximately €32M at the end of June.

Which advanced nuclear startups have more than $10 million in revenue?

X-energy and newcleo are the only ranked advanced nuclear startups whose selected revenue figures exceed approximately $10M. The reporting periods differ, so these numbers should be read as disclosed revenue figures rather than perfectly comparable annual totals.

X-energy generated $90M in services revenue during the first half of 2026. Newcleo reported €32.8M for FY2025, equivalent to roughly $37M using an indicative exchange rate for that period.

Standard Nuclear comes next with $5.33M for the first half of 2026. Oklo reported $1.21M, while the other ranked companies disclosed substantially smaller figures.

Of the eight ranked startups, two have selected revenue figures above the $10M threshold, one is between $5M and $10M, and five are below $2M or the approximate currency equivalent.

That concentration explains part of the disconnect between the industry's huge project announcements and the small numbers appearing in financial statements. Most developers are still years away from the revenue levels normally associated with major energy companies.

Are nuclear fuel startups making money faster than reactor developers?

Nuclear fuel startups are beginning to generate product revenue earlier than many reactor developers, which are still waiting for their first commercial electricity sales. X-energy and newcleo nevertheless occupy the top two positions in the overall advanced nuclear startup ranking.

Standard Nuclear is a useful example. Its first-half 2026 revenue reached $5.33M, including approximately $3.1M from fuel products. ASP Isotopes generated $800K from nuclear-fuels activities during the same period.

Both businesses can sell products or services that support reactor development without waiting for a new fleet of reactors to start generating electricity.

That gives fuel manufacturers a potentially shorter route to early revenue, although fuel qualification, manufacturing approvals and production costs remain substantial challenges.

Reactor-focused companies face a more complicated path. A new power plant generally requires years of design work, licensing, financing, construction and testing before electricity sales can begin.

The difference is already visible across the ranking. X-energy reported services revenue, newcleo generated products and services revenue, and Standard Nuclear earned money from fuel-related products and services. NANO Nuclear's first recognized revenue came from nuclear transportation.

Meanwhile, Kairos Power's Hermes 2 plant is expected to supply up to 50 MWe to the Tennessee Valley Authority grid, supporting Google's electricity needs. TerraPower's agreement with Meta targets initial Natrium deployments as early as 2032.

For the moment, revenue in advanced nuclear mostly comes from building the industry rather than operating its future power plants.

Which advanced nuclear startups have the biggest contracts but little disclosed revenue?

General Matter, Radiant Industries, TerraPower and Kairos Power have some of the most substantial commercial agreements among advanced nuclear startups without comparable recognized revenue figures.

General Matter received a $900M Department of Energy task order announced in January 2026 to support domestic HALEU enrichment capacity.

Radiant Industries announced an agreement with the U.S. Army worth up to $750M in August 2026, covering the development and delivery of 15 Kaleidos microreactors.

TerraPower has a major commercial agreement with Meta covering up to eight Natrium plants, while Kairos Power is developing its first commercial-scale reactor project under an agreement involving Google and the Tennessee Valley Authority.

These commitments cover different parts of the market: nuclear fuel, military microreactors and commercial electricity generation.

The amounts and project sizes cannot be added together as company revenue. Some cover future construction or delivery, others are conditional agreements, and some establish potential capacity without guaranteed electricity purchases.

Startup	Disclosed commitment or scale	Type of commercial evidence
Radiant Industries	Up to $750M	Government contract award / bookings
General Matter	$900M	Government task-order award
TerraPower	Up to 8 Natrium plants	Planned project units / commercial agreement
Kairos Power	Up to 50 MWe	Contracted power capacity / PPA
Aalo Atomics	1 critical test reactor	Operational reactor demonstration
Blykalla	6 proposed units	Proposed reactor projects
Deep Fission	Up to 150 MW	Master energy purchase agreement capacity
Antares Nuclear	1 U.S. Army installation selection	Government project selection

Can TerraPower become one of the biggest advanced nuclear companies?

TerraPower could become one of the largest advanced nuclear businesses if it successfully delivers its planned Natrium projects, but the company currently remains unranked by revenue.

The biggest development came in March 2026, when the U.S. Nuclear Regulatory Commission issued the construction permit for its first Natrium reactor project in Kemmerer, Wyoming.

TerraPower had submitted its application in March 2024. The permit therefore marked the conclusion of an important two-year regulatory process and authorized construction of the nuclear facility. A separate operating license will still be needed before the plant can operate.

The company also announced an agreement with Meta in January 2026 covering up to eight Natrium plants. The proposed fleet would deliver up to 2.8 GW of baseload electricity and potentially reach 4 GW of output when including integrated energy-storage capacity.

Meta's initial commitment supports two units, with rights to energy from up to six additional units.

That gives TerraPower a clearer route toward a multi-plant commercial business than many earlier-stage reactor developers. Its biggest challenge now is turning permitted projects and customer agreements into financed, completed facilities.

We still cannot establish TerraPower's current revenue position against the ranked startups because no sufficiently comparable figure has been disclosed.

Is Kairos Power closer than other startups to selling nuclear electricity?

Kairos Power is one of the more advanced reactor startups in moving toward commercial electricity sales, thanks to its Hermes 2 project and agreements involving Google and the Tennessee Valley Authority.

In April 2026, Kairos Power began construction work on Hermes 2 in Oak Ridge, Tennessee. The facility is designed to deliver up to 50 MWe and forms the first deployment under Google's broader agreement for up to 500 MWe of advanced nuclear power.

The electricity will be purchased by the Tennessee Valley Authority through a binding power-purchase agreement announced in August 2025.

There is now a named site, an identified electricity buyer, construction activity and a planned operating date. That's more concrete than the early-stage commercial plans of many competing reactor developers.

Kairos Power has also followed a staged development strategy, using demonstration reactors to test its fluoride-salt-cooled technology before pursuing larger commercial plants.

The company currently remains unranked on revenue because its publicly available commercial disclosures do not establish a comparable recognized sales figure.

Still, Hermes 2 puts Kairos Power among the startups worth watching as the industry approaches its first new commercial electricity deliveries.

Could Radiant Industries become a major microreactor supplier?

Radiant Industries has one of the strongest government procurement commitments among microreactor startups, with an Army agreement worth up to $750M for 15 Kaleidos reactors announced in August 2026.

The Kaleidos microreactor is designed to be transported and deployed at locations requiring reliable power, including military installations and remote industrial sites.

Radiant's agreement was awarded under the U.S. Army's Janus program. It covers future development and deployment rather than revenue already recognized.

The company's progress extends beyond the contract announcement. In August 2026, its Kaleidos demonstration unit arrived at Idaho National Laboratory for testing, while work was progressing on its manufacturing facility in Oak Ridge, Tennessee.

Radiant's investors have described initial Army deliveries as targeted for 2028.

If the company can complete reactor testing, manufacturing and deployment successfully, the Army contract could help establish a repeatable commercial product.

For now, Radiant remains unranked by revenue. Its commercial significance comes from the size of the procurement commitment and the progress of its reactor-testing program.

Why is the U.S. government spending billions on advanced nuclear fuel?

The U.S. government is spending billions on nuclear fuel because many advanced reactors will need enrichment and manufacturing capabilities that are not yet available at sufficient commercial scale.

In January 2026, the Department of Energy announced $2.7B in uranium enrichment task orders. The awards included $900M for General Matter to develop domestic HALEU enrichment capacity, alongside other agreements supporting uranium enrichment.

HALEU contains between 5% and 19.75% uranium-235, a higher concentration than the fuel typically used by existing commercial light-water reactors.

Several advanced reactor designs depend on this fuel, creating a potential supply bottleneck as more projects move toward construction.

The Department of Energy also awarded $28M to Global Laser Enrichment for work on advanced enrichment technology.

This government spending creates opportunities for startups working on enrichment, fuel production, transportation and related engineering. Standard Nuclear and ASP Isotopes are already reporting revenue from parts of the fuel industry, while General Matter has a substantial government award.

The $900M General Matter award is a future work commitment rather than recognized annual revenue. Its size shows how seriously the United States is treating the need for domestic advanced nuclear fuel capacity.

Are advanced nuclear startups growing quickly or struggling to make money?

Advanced nuclear startup revenue is growing quickly at several companies, but profitability remains elusive because reactor and fuel development requires enormous spending before commercial production reaches scale.

X-energy increased first-half services revenue by 165% year over year, while Standard Nuclear reported growth of approximately 473%. Newcleo's first-half revenue rose 46%, although its preceding annual revenue had declined.

NuScale offers a contrasting example. Its first-half 2026 revenue fell 97% after earlier engineering work stopped generating the same level of recognized sales.

Profitability is equally uneven. X-energy reported approximately $152M in direct expenses against $90M of services revenue during the first half of 2026. Newcleo reported an €82M net loss, and Standard Nuclear's first-half cost of revenue exceeded sales by approximately $1.23M.

Oklo's operating loss reached approximately $124M during the first half of 2026, against $1.21M in revenue.

These companies are spending heavily on engineering teams, reactor design, licensing, testing facilities and manufacturing capacity.

The companies with accelerating revenue have demonstrated stronger commercial activity. But attractive margins, repeatable construction economics and low-cost reactor manufacturing remain largely unproven.

Which countries have the strongest advanced nuclear startups?

The United States clearly dominates the current advanced nuclear startup revenue ranking, accounting for six of the eight ranked companies.

X-energy, Standard Nuclear, Oklo, ASP Isotopes, NuScale Power and NANO Nuclear Energy are headquartered in the United States.

Newcleo is based in the United Kingdom, while Steady Energy is headquartered in Finland.

The United States also has a substantial pipeline of companies that remain unranked, including TerraPower, Kairos Power, Radiant Industries, General Matter, Aalo Atomics, Deep Fission and Antares Nuclear.

Europe has a growing group of developers working on different reactor technologies. France is home to companies such as Jimmy Energy, Hexana, Stellaria, Calogena, Blue Capsule, Otrera and Archeos. Sweden has Blykalla, while Denmark has Seaborg Technologies and Copenhagen Atomics.

Canada has notable advanced reactor developers including ARC Clean Technology and Moltex Energy.

Which other advanced nuclear startups could become important?

Several currently unranked advanced nuclear startups are making credible technical progress, although their commercial revenue remains undisclosed or too difficult to compare reliably.

Aalo Atomics reported reaching criticality in a reactor demonstration in July 2026 and has been developing factory-built sodium-cooled reactors.

Blykalla is working on lead-cooled reactor projects in Sweden, while Deep Fission is pursuing an underground microreactor design and has announced a long-term energy-purchase agreement covering potential generating capacity.

France has a particularly active group of companies developing smaller nuclear systems for industrial applications. Jimmy Energy focuses on nuclear heat, Stellaria is developing molten-salt reactor technology, and Hexana is pursuing fast-reactor technology.

Some developers are even earlier in their commercialization process. Copenhagen Atomics has a historical FY2019 sales figure of DKK 548K, but more recent turnover is not sufficiently established for a current numerical ranking. Terrestrial Energy has discussed project economics for its molten-salt reactors without reporting comparable recognized company revenue.

Their eventual commercial scale will depend on licensing, demonstration results, financing, manufacturing and customer demand.

Startup	Reported scale or activity	Revenue limitation
Valar Atomics	Reactor development	Not disclosed
Last Energy	Development pipeline	Not disclosed
Blue Energy	Modular nuclear plant development	Not disclosed
Jimmy Energy	1 industrial reactor project	No comparable revenue figure
Hexana	1 advanced reactor program	No comparable revenue figure
Stellaria	1 demonstrator project	No comparable revenue figure
Natura Resources	1 demonstration reactor	No comparable revenue figure
ARC Clean Technology	1 proposed reactor project	No comparable revenue figure
Thorizon	1 reactor platform	No comparable revenue figure
Seaborg Technologies	Reactor platform development	Not disclosed
Copenhagen Atomics	DKK 548K, FY2019	Historical annual revenue
Calogena	1 reactor design under review	No comparable revenue figure
Blue Capsule	1 high-temperature reactor program	No comparable revenue figure
Otrera	1 sodium-cooled reactor program	No comparable revenue figure
Archeos	1 proposed reactor project	No comparable revenue figure
Terrestrial Energy	Reactor development agreements	Not disclosed
Moltex Energy	Reactor licensing	Not disclosed

How big are advanced nuclear startups compared with established nuclear companies?

Advanced nuclear startups remain much smaller than established nuclear equipment and services businesses, which already benefit from decades of commercial operations.

GE Vernova reported $1.57B from its Nuclear Power business during the first half of 2026, although that figure includes substantial activities connected to conventional nuclear power.

Westinghouse Electric Company's new-build business generated approximately $800M in FY2025, while Holtec Nuclear Corporation reported $577M in consolidated FY2025 revenue.

These are different financial scopes, so the figures should not be treated as a direct ranking of advanced reactor sales. They do show how much existing nuclear infrastructure contributes to the industry's current revenue.

X-energy's $90M in first-half services revenue is substantial for an advanced nuclear startup but remains far below the sales generated by these established businesses.

Incumbents also have existing customers, service operations and manufacturing relationships. Startups generally need to build those capabilities while developing and licensing new technologies.

GE Vernova, Westinghouse and Holtec are included here only as scale comparisons. They are excluded from the startup ranking because they do not meet the startup eligibility rules.

Which advanced nuclear startups could make the most revenue in the next decade?

X-energy has the strongest current revenue position, while TerraPower, Kairos Power and several fuel and microreactor developers have projects that could eventually generate much larger commercial sales.

X-energy has the advantage of already generating substantial services revenue while working on reactor and fuel projects.

Newcleo can build on existing industrial products and services, and Standard Nuclear has begun generating revenue from commercial fuel deliveries.

TerraPower's Natrium projects and Kairos Power's Hermes 2 development could eventually create substantial electricity revenue if construction and licensing progress as planned. Radiant's military procurement agreement offers a different route through reactor manufacturing and delivery.

General Matter could also become an important commercial fuel supplier as domestic enrichment capacity expands.

The biggest uncertainty is the speed at which these companies can move from development projects to repeatable manufacturing and operation.

A developer with several large power agreements may eventually generate far more revenue than a company currently earning millions from engineering services. But those future sales depend on plants actually being financed, built and operated.

Today, X-energy's revenue lead is well supported. The future revenue ranking remains open because most of the industry's planned reactor capacity has yet to become operational.

What are the top advanced nuclear startups by revenue today?

X-energy is currently the clear revenue leader among advanced nuclear startups, followed in order by newcleo, Standard Nuclear, Oklo, ASP Isotopes, NuScale Power, NANO Nuclear Energy and Steady Energy.

X-energy's $90M in first-half 2026 services revenue places it far ahead of the other ranked startups. Newcleo has a meaningful industrial business with €32.8M in FY2025 revenue, while Standard Nuclear is growing rapidly through nuclear fuel products and services.

The remaining five ranked companies have much smaller disclosed sales, and several are still spending vastly more on development than they earn from customers.

What makes this market unusual is the difference between current company revenue and the scale of future electricity projects. TerraPower, Kairos Power, Radiant Industries and General Matter have secured major agreements without reporting comparable revenue figures.

For now, the biggest advanced nuclear startups by revenue are mainly making money from engineering, equipment, fuel and related industrial services. X-energy leads that market today, while the much larger business of producing and selling electricity from new reactors is still taking shape.