Company lists · Data refreshed September 2026
Top 25 Nuclear engineering companies worldwide
RevenueBase identified 673 nuclear engineering companies worldwide as of September 2026 and tracks 110,645 professional contacts across them, including 30,685 with verified work emails. The United States is the largest market and London the largest hub.
This list covers nuclear engineering companies worldwide, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 21, 2026. Country and city lists for nuclear engineering companies follow the table.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest nuclear engineering companies worldwide
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 12,439 contacts → | ||||
Partial evidence “Framatome is an international leader in nuclear energy recognized for its innovative, digital and value added solutions for the global nuclear fleet.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 2 | 11,121 contacts → | ||||
Indirect evidence “Opérateur international reconnu dans le domaine des matières nucléaires, Orano apporte des solutions aux défis actuels et futurs, dans l’énergie et la santé.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 3 | 10,898 contacts → | ||||
Partial evidence “Westinghouse Electric Company is the world's leading supplier of safe and innovative nuclear technology.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 4 | 9,297 contacts → | ||||
Indirect evidence “Atkins is now AtkinsRéalis.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 5 | 6,518 contacts → | ||||
Strong evidence “Assystem, one of the world's leading independent nuclear engineering companies, is committed to accelerating the energy transition.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 6 | 3,832 contacts → | ||||
Indirect evidence “At BWX Technologies, Inc.(NYSE: BWXT), we are People Strong, Innovation Driven.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 7 | 2,270 contacts → | ||||
Partial evidence “Cameco is a global nuclear energy company.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 8 | 2,229 contacts → | ||||
Partial evidence “Canada's premier nuclear science and technology organization.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 9 | 1,780 contacts → | ||||
Partial evidence “Edvance, a joint subsidiary of EDF and Framatome, is responsible for the design and implementation (studies, procurement assistance, assembly and commissioning) of nuclear islands…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 10 | 1,664 contacts → | ||||
Strong evidence “Onet Technologies has 40 years of experience in the nuclear industry, with a strong expertise in engineering and services for reactor maintenance; dismantling, decommissioning and…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 11 | 1,592 contacts → | ||||
Partial evidence “Cavendish Nuclear is a core part of Babcock International Group’s Nuclear Sector.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 12 | 1,537 contacts → | ||||
Indirect evidence “Subsidiary of the world-leading VINCI group, NUVIA is an international company that has been operating on highly regulated and sensitive industrial sites for over 60 years.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 13 | 1,453 contacts → | ||||
Partial evidence “INVAP is a technology base company, which makes multidisciplinary developments in several different areas:* The most important of these areas are nuclear, space and certain…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 14 | 1,315 contacts → | ||||
Indirect evidence “TechnicAtome est spécialisée, depuis plus de 50 ans, dans la conception, la réalisation, la mise en service et le maintien en conditions opérationnelles des réacteurs nucléaires…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 15 | 1,266 contacts → | ||||
Partial evidence “Nucleoeléctrica Argentina S.A.(NASA) es una empresa generadora de energía eléctrica, operadora de las centrales nucleares argentinas y encargada de la gestión de los proyectos…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 16 | 1,254 contacts → | ||||
Partial evidence “EnergySolutions is an international nuclear services company headquartered in Salt Lake City, Utah, and Charlotte, North Carolina, with operations across the United States and…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 17 | 1,079 contacts → | ||||
Indirect evidence “À propos de SPIE Nucléaire Filiale de SPIE France, SPIE Nucléaire est le partenaire de référence multi-technique dans la conception, la réalisation, les travaux de modification…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 18 | 1,055 contacts → | ||||
Partial evidence “X-energy is delivering the next generation of carbon-free energy by reinventing nuclear power.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 19 | 913 contacts → | ||||
Partial evidence “TerraPower is a leading nuclear innovation company that strives to improve the world through nuclear energy and science.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 20 | 684 contacts → | ||||
Partial evidence “Centrus Energy is a trusted American supplier of nuclear fuel and services for the nuclear power industry, helping meet the growing need for clean, affordable, carbon-free energy.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 21 | 640 contacts → | ||||
Partial evidence “Since launching in 2021 newcleo has quickly established itself as innovator in the field of nuclear energy.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 22 | 579 contacts → | ||||
Indirect evidence “KEPCO E&C was founded in 1975 with the objective of obtaining core technology.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 23 | 558 contacts → | ||||
Indirect evidence “We are now Orano!” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 24 | 539 contacts → | ||||
Indirect evidence “Urenco is an international supplier of enrichment services and fuel cycle products with sustainability at the core of its business.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 25 | 487 contacts → | ||||
Strong evidence “TECNATOM was set up in 1957 as a Spanish engineering company specialising in guaranteeing the operation and maintenance of nuclear power plants to the highest levels of safety.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: nuclear engineering companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names nuclear engineering companies.
- Partial evidence
- Its own public description names part of nuclear engineering companies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name nuclear engineering companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 673 nuclear engineering companies worldwide
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Nuclear engineering companies worldwide at a glance
As of Sep 21, 2026Companies by employee count
Email recency is reported on each country list linked below.
How this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among nuclear engineering companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- Coverage
- Every country. Country and city lists for nuclear engineering companies are linked below.
- What qualifies
- Companies worldwide whose own description of what they do matches “nuclear engineering companies”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names nuclear engineering companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among nuclear engineering companies, and records with no verified work email.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every listed company carries at least one verified work email, 30,685 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on September 21, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Nuclear engineering companies by location
3 lists · largest firstEvery Nuclear engineering companies list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names nuclear engineering companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many nuclear engineering companies are there worldwide?
RevenueBase identified 673 nuclear engineering companies worldwide as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
Framatome, headquartered in Courbevoie, tops this list with the largest team on record.
Which country has the most nuclear engineering companies?
The United States leads with 180 companies, followed by France (71) and the United Kingdom (54). Every nuclear engineering companies list by country and city is linked on this page.
Which city has the most nuclear engineering companies?
London leads with 9 headquartered companies, followed by Toronto (8) and Lyon (7).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 30,685 verified decision-maker contacts tracked across these 673 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 21, 2026.
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About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.