Four organisations enrich the world's uranium
Natural uranium is 0.71% U-235. Almost every commercial reactor needs 3% to 5%. The industry that closes that gap consists of four organisations.
Rosatom holds roughly 43% of world capacity. Urenco, Orano and CNNC hold most of the rest. Together the top three account for about 88% of the 68,076 thousand SWU of annual capacity, and all four together for about 99%. The remainder — Japan’s JNFL and Brazil’s INB — is a rounding error at 355 thousand SWU.
Why so few
Enrichment is hard in a specific way. The two isotopes of uranium are chemically identical, so no chemical process separates them. The only usable difference is mass, about 1.3%, and every enrichment technology ever deployed is a way of exploiting that difference over and over.
Gaseous diffusion, the original method, pushed uranium hexafluoride through porous barriers thousands of times in series. It worked, and it consumed staggering amounts of electricity: France’s Georges Besse I plant used roughly 3% of the country’s electricity and had three reactors built at Tricastin specifically to power it.
The gas centrifuge replaced it and uses about 2% as much energy per unit of work. Urenco commercialised it under the 1970 Treaty of Almelo, signed by the UK, the Netherlands and West Germany. That single technical shift is why enrichment is cheap today — and why it consolidated. A centrifuge plant is capital-intensive, takes the better part of a decade to build, and is only economic at scale.
There is a second barrier that has nothing to do with economics. The same centrifuges that enrich uranium to 5% will enrich it to 90% if you keep going. Enrichment technology is therefore export-controlled under the Nuclear Suppliers Group, and a new entrant faces not just capital cost but non-proliferation politics.
Why it suddenly mattered
For decades this concentration was a curiosity. Then Russia invaded Ukraine.
Russia supplied roughly a fifth of US enrichment services. The United States banned Russian uranium imports in May 2024, with waivers running to 2027. Europe has been reducing its dependence more slowly. Both are now funding new Western capacity — the US Department of Energy committed $2.7 billion over ten years in January 2026 — but centrifuge plants do not appear on political timescales.
The uncomfortable arithmetic: Orano’s Georges Besse II is expanding from 7,500 to 10,000 thousand SWU by 2030. Urenco is adding 700 thousand SWU at Eunice. Those are real additions, and together they replace a fraction of what Rosatom supplies.
See the full capacity table and each plant on the enrichment stage page.