America’s nuclear fleet is running hotter on foreign uranium and cooler on fresh fuel — a combination that should make anyone who cares about the grid sit up straight. In 2025, U.S. commercial nuclear power plants loaded 40.9 million pounds of uranium into their cores, a 15% drop from the year before, even as operators quietly expanded their stockpiles. And 93% of the uranium fueling those reactors came from overseas.
U.S. nuclear fuel is mostly foreign — by design, and by risk
The headline number is stark: foreign sources supplied 93% of the uranium delivered to U.S. nuclear reactors in 2025, leaving just 7% from domestic production. That dependence isn’t new, but the gap is widening at the exact moment nuclear power is being asked to backstop data centers, electrified transport, and an aging grid.
At the same time, reactor operators eased off on how much fresh fuel they pushed into cores. Uranium in fuel assemblies loaded into civilian reactors totaled 40.9 million pounds (measured as U3O8 equivalent), down from 48.1 million pounds in 2024. That’s a 15% cut in core loading in a single year.
This doesn’t mean reactors are shutting down en masse. Instead, it points to a strategy shift: stretch existing fuel further, line up long-term contracts, and build a bigger buffer in case the global uranium market gets turbulent.
Loading less fuel, stockpiling more
While core loads fell, total commercial uranium inventories moved in the opposite direction. By the end of 2025, total U.S. commercial uranium stocks reached 170 million pounds, up 9% year over year.
Those stocks aren’t just neat rows of finished fuel rods. They span the entire nuclear fuel cycle:
- Raw uranium that still needs chemical conversion
- Material being put through isotopic enrichment
- Fabricated fuel ready to be slid into reactor cores
Reactor operators themselves owned 118 million pounds of that total, a 3% increase over 2024. Suppliers — the converters, enrichers, fabricators, producers, brokers, and traders that keep uranium moving — held 51 million pounds, a jump of 27% in a single year.
In other words, the industry is taking less fresh fuel into the core each year while stacking more uranium in the warehouse. That’s not an efficiency miracle; it’s an insurance policy.
360 million pounds of demand, and a widening gap
Look just a decade out and the scale of that insurance problem comes into focus. Over the next 10 years, U.S. nuclear utilities expect to need about 360 million pounds of uranium to keep their reactors running.
They’ve already contracted 174 million pounds through long-term purchase agreements. That leaves about 186 million pounds of projected demand that isn’t yet covered by contracts — a volume that will have to be negotiated in a market where prices are already creeping up and foreign enrichment is doing most of the heavy lifting.
That unfilled demand doesn’t equate to an immediate crisis, but it’s a clear vulnerability. If geopolitics, trade disputes, or supply disruptions hit major suppliers, U.S. utilities would be forced to scramble — or draw down the stockpiles they’ve just spent years building.
Inside the nuclear fuel pipeline
Behind every fuel rod is a surprisingly complex international supply chain. In 2025, uranium producers and operators delivered 32 million pounds of natural uranium feed to enrichment plants in the U.S. and abroad.
Only 37% of that material was enriched domestically. The remaining 63% was shipped overseas for enrichment, including significant volumes to France and Russia. That is where America’s foreign reliance deepens: it’s not just about where the ore comes from, but where the enrichment capacity sits.
To turn that raw feed into reactor-ready fuel, U.S. utilities purchased 13 million separative work units (SWU) of enrichment services in 2025 from four commercial sellers. The average price paid was $108.70 per SWU, up 11% from $97.66 the year prior.
Foreign facilities provided 77% of those enrichment services. Russian plants alone supplied 26% of the total, followed by France at 18%, the United Kingdom at 14%, and the Netherlands at 8%. U.S. enrichers covered the remaining 23%.
This is the part of the nuclear story that rarely makes headlines: America’s reactors may be on U.S. soil, but the fuel cycle that keeps them running is deeply, structurally international.
Less uranium bought, at higher prices
There’s another twist in this picture: the nuclear sector is buying less uranium overall, and paying more per pound. Total uranium procurement in 2025 reached 46.9 million pounds, down 16% from 55.9 million pounds in 2024.
Yet the weighted-average price rose 11%, from $52.71 per pound in 2024 to $58.46 in 2025. That’s a familiar pattern across energy markets — volumes dip or flatten, but prices keep inching up as sellers gain leverage and buyers race to secure long-term supply.
Most of that uranium arrived under long-term contracts. In 2025, 87% of total deliveries were covered by these agreements at an average price of $55.91 per pound. The remaining 13% came from the spot market, where utilities paid a much steeper average of $76.01 per pound.
Operators also moved to lock in more future supply, signing 22 new purchase contracts for 4 million pounds of uranium with 2025 delivery at an average cost of $70.46 per pound. The signal is clear: utilities expect the nuclear fuel market to remain tight, and they’re willing to pay a premium for predictability.
Why nuclear’s fuel math suddenly matters
On paper, nuclear power in the U.S. already plays a quiet but crucial role in decarbonization. It runs around the clock, has near-zero operational emissions, and underpins the stability of the grid in regions heavily invested in solar and wind.
But that reliability rests on a fuel strategy that leans heavily on foreign mining and foreign enrichment, even as core loading falls and commercial stockpiles grow. The combination of 93% foreign-sourced uranium and 77% foreign-provided enrichment is hard to square with the way nuclear power is usually marketed: as domestic, steady, and secure.
At the same time, the 15% reduction in uranium loading into reactor cores underscores just how carefully operators are tuning their fuel strategies. Running longer on each core load, optimizing refueling outages, and using higher-assay fuel where possible all help squeeze more megawatt-hours out of each pound of uranium. But there’s a limit to how far that optimization can go without fresh investment and new technology.
Meanwhile, the grid itself is becoming hungrier. Data centers, electrified transport, industrial decarbonization — all of it adds demand that nuclear is uniquely suited to serve, if it can keep the fuel coming.
How the U.S. could rebalance its nuclear fuel strategy
The numbers from 2025 don’t dictate a single policy answer, but they do narrow the options.
One path is to keep doubling down on long-term contracts with foreign suppliers, treating uranium much like imported crude oil: a strategic commodity backed by diplomacy, trade deals, and stockpiles large enough to weather shocks. That’s essentially what the current system looks like, just with more transparency on the fuel math.
Another is to treat nuclear fuel supply as a strategic capability in its own right. That would mean:
- Expanding domestic uranium production where economically and environmentally viable
- Investing in additional U.S.-based enrichment capacity
- Diversifying enrichment contracts away from any single foreign provider
- Maintaining — or even further growing — commercial uranium inventories as a buffer
None of that is quick. Bringing new mines online, licensing enrichment facilities, and financing fuel-cycle infrastructure are decade-scale projects. The 10-year demand forecast of 360 million pounds makes that timeline uncomfortably tight.
That’s why the current stockpiling trend matters. The 170 million pounds sitting in commercial hands by the end of 2025 aren’t just a number; they’re a bridge. How long that bridge lasts depends on how aggressively the U.S. decides to rebuild its fuel supply chain at home and how carefully utilities manage that still-unfilled 186 million pound demand gap.
What This Means
Nuclear power in the U.S. is at a strange inflection point. On one hand, reactor operators are proving they can run with less fresh fuel loaded each year while steadily padding their uranium reserves. On the other, the system that feeds those reactors is more exposed to foreign supply and foreign enrichment than most people realize.
The core facts are simple: 93% of the uranium feeding U.S. reactors is foreign-sourced, core loads dropped 15% to 40.9 million pounds in 2025, and commercial uranium stocks climbed to 170 million pounds. Layer a decade-long demand forecast of 360 million pounds on top of that, and the message is hard to miss.
If the country wants nuclear to shoulder a bigger share of a cleaner, more electrified economy, it will need to care as much about where the fuel comes from — and how much of it is on hand — as it does about building new reactors. The numbers from 2025 are a quiet warning that the time to make those choices is now, while the stockpiles are high and the lights are still on.
Photo: St Stev / BY-NC-ND via Openverse
