HALEU (High-Assay Low-Enriched Uranium) is uranium enriched to between 5% and 20% uranium-235 — the critical fuel that most next-generation small modular reactors require but that almost no one can produce at scale. As of March 2026, Centrus Energy at its American Centrifuge Plant in Piketon, Ohio is the only US facility producing HALEU, having delivered over 900 kg to the DOE. The reactors that need HALEU include TerraPower Natrium, X-energy Xe-100, Kairos Power Hermes, and Oklo Aurora. Until the 2024 ban on Russian enriched uranium imports, Russia (Rosatom/TENEX) was the only commercial HALEU supplier globally. The DOE has committed over $2.7 billion to building domestic HALEU and LEU enrichment capacity — making fuel supply the most critical bottleneck in the advanced reactor deployment timeline.
As mined from the ground. Must be enriched for use in power reactors.
Standard fuel for conventional PWRs and BWRs. Used in 440+ operating reactors worldwide, and some SMRs like BWRX-300 and NuScale VOYGR.
Required by most advanced SMRs and microreactors: Natrium, Xe-100, Hermes, Aurora, Radiant. Enables smaller cores, longer fuel cycles, higher burnup.
Used in naval reactors and weapons. Not used in civilian power. The 20% threshold is the key nonproliferation boundary.
Most next-generation reactor designs require HALEU because higher enrichment enables smaller, more efficient cores with longer refueling intervals. The following advanced reactors all depend on HALEU availability to meet their deployment timelines.
| REACTOR | DEVELOPER | TYPE | FUEL FORM | HALEU ENRICHMENT | TIMELINE |
|---|---|---|---|---|---|
| Natrium | TerraPower | SFR (345 MWe) | Metallic U-Zr alloy | ~12-15% | 2030 (Kemmerer, WY) |
| Xe-100 | X-energy | HTGR (80 MWe) | TRISO pebble fuel | 15.5% | 2030s (Dow Seadrift, TX) |
| Hermes | Kairos Power | FHR (35 MWt demo) | TRISO pebble fuel | 19.75% | 2027 (Oak Ridge, TN) |
| Aurora | Oklo | Fast Reactor (15 MWe) | Metallic HALEU | ~19.75% | 2027 (INL, ID) |
| BANR | Radiant Industries | HTGR Microreactor (1 MWe) | TRISO fuel | 19.75% | 2028+ |
| MMR | Ultra Safe Nuclear | HTGR Microreactor (5 MWe) | FCM TRISO fuel | 19.75% | 2028+ (Chalk River, ON) |
Building domestic HALEU production capacity is the most urgent infrastructure challenge in the US advanced reactor program. After the 2024 ban on Russian enriched uranium, the DOE has committed over $2.7 billion to fund enrichment and fuel fabrication through the HALEU Availability Program.
Only US producer of HALEU. 900+ kg delivered to DOE by June 2025. $900M DOE task order (Jan 2026) for full-scale cascade operational within 42 months. $3.6B traditional enrichment order book.
NRC authorized enrichment up to 10% (LEU+) Sep 2025. First LEU+ production 2025; deliveries to fuel fabricators 2026. UK HALEU facility at Capenhurst: design phase, construction 2028, production early 2030s.
Plans new US enrichment facility: NRC license application H1 2026, production by 2031, total cost ~$5B. Full-spectrum nuclear fuel cycle services globally.
NRC Part 70 SNM license approved Feb 2026 (3 months early). Building construction began Nov 2025. First commercial TRISO fuel facility in the Western world.
TRISO fuel manufacturing capability for military/defense microreactors (Project Pele) and NASA space nuclear applications. Naval reactor components supplier.
Advanced fuel operating ~1000C cooler than standard fuel. Enriched UZr2 fuel samples co-extruded with INL. Irradiation testing began Nov 2025. Enhanced safety, economics, proliferation resistance.
Until the 2024 US ban on Russian enriched uranium imports, Russia was the world's only commercial supplier of HALEU through Rosatom subsidiary TENEX. This created a single point of failure for the entire advanced reactor industry. The DOE HALEU Availability Program, mandated by the FY2024 NDAA, is the US government's response — targeting domestic production capacity that can fuel the first wave of advanced reactors.
Congressional mandate (FY2024 NDAA). $2.7B+ awarded for HALEU and LEU enrichment. Falling behind targets with demonstration-scale production only. Critical for advanced reactor deployment.
US banned Russian enriched uranium imports in 2024. Russia (TENEX/Rosatom) was historically the only commercial HALEU supplier. Created urgent need for domestic/allied HALEU production capacity.
Before uranium can be enriched to HALEU levels, it must be mined and converted. The uranium mining sector is experiencing a renaissance driven by new reactor demand and geopolitical supply concerns. Key publicly traded miners supplying the HALEU pipeline include Cameco, Uranium Energy Corp, Denison Mines, NexGen Energy, and Energy Fuels.
| COMPANY | TICKER | FACILITY / REGION | STATUS | NOTES |
|---|---|---|---|---|
| Cameco Corporation | CCJ | Cigar Lake + McArthur River, Saskatchewan, Canada | Operational | World's largest publicly traded uranium company. Also co-owns Westinghouse with Brookfield. Vertically integrated from mining through fuel services. |
| Kazatomprom | KAP | Multiple ISR mines, Kazakhstan | Operational | Kazakhstan state-owned, London-listed. World's largest uranium producer supplying approximately 25% of global uranium. |
| Uranium Energy Corp | UEC | Multiple ISR operations, Texas and Wyoming | Operational | US-based uranium miner using ISR operations. Positioned to benefit from domestic uranium supply mandates and the ban on Russian enriched uranium imports. |
| Denison Mines | DNN | Wheeler River — Phoenix ISR Mine, Saskatchewan, Canada | Under Construction | Wheeler River project with Phoenix ISR mine construction starting March 2026. High-grade deposit in the Athabasca Basin. |
| NexGen Energy | NXE | Rook I Project, Athabasca Basin, Saskatchewan, Canada | Development | Rook I project — one of the world's largest high-grade undeveloped uranium deposits in the Athabasca Basin. |
| Energy Fuels | UUUU | White Mesa Mill, Utah + multiple mine sites | Operational | US uranium producer and rare earth elements processor. Diversified operations across the western United States. |
HALEU is the single biggest bottleneck in the advanced reactor deployment timeline. Without it, none of the most promising next-generation SMRs — Natrium, Xe-100, Hermes, Aurora — can fuel their first cores. The US has one operational HALEU producer (Centrus, Piketon, OH) with demonstration-scale output of roughly 900 kg delivered. The $2.7B+ DOE investment is substantial but the program is behind its own targets. The 2024 Russian uranium ban removed the only alternative supplier. Until Centrus scales to its full 6-12 MTU/year cascade and TRISO-X completes its Oak Ridge facility, the advanced reactor industry depends on a single building in rural Ohio. That is both the opportunity and the risk.