Los Alamos Plutonium Facility (PF-4)
Los Alamos National Laboratory (NNSA), Los Alamos, New Mexico
PF-4 is the plutonium facility at Los Alamos National Laboratory in New Mexico where the United States assembles plutonium pits for nuclear weapons. It had made about 30 war-reserve pits since 2000, according to a 2023 NNSA fact sheet, and is being equipped to reach 30 pits per year. Los Alamos was also the Manhattan Project laboratory where the first atomic bombs were designed.
- Company
- Los Alamos National Laboratory (NNSA)
- Status
- Operating
- Opened
- Not stated
- Employees
- Not stated
- Industry
- Aerospace and defense
- Revised
- November 12, 2026
What is made here
Assembles plutonium pits, the cores of nuclear weapons, for the U.S. stockpile.
Facts
| Mission | PF-4 assembles pits; Lawrence Livermore designs the pit and the Kansas City National Security Campus makes non-plutonium components shipped to PF-4 (federal: energy.gov) |
|---|---|
| Past output | An operating facility that has made approximately 30 war-reserve pits since 2000 (federal: energy.gov) |
| Target rate | Los Alamos target is 30 war-reserve pits per year, within a national goal of at least 80 per year across two sites (federal: energy.gov) |
| W87-1 | The 2023 NNSA fact sheet expected the first production-unit war-reserve pit, for the W87-1 warhead, in 2024 (federal: energy.gov) |
Figures are as stated by the source named next to each one. Company figures are the company's own claims.
Can you visit?
We haven't found a public tour of this factory. See factory tours in New Mexico.
Sources
- NNSA 2023 Pit Production Fact Sheet (federal, checked November 12, 2026)
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