The last U.S. nuclear weapons test was conducted on September 23, 1992, at the Nevada Test Site (now the Nevada National Security Site).

Key facts

  • The test was an underground nuclear explosion codenamed Divider.
  • It was the 1,030th announced U.S. nuclear test (1,054 including joint U.S.–UK tests, depending on counting method).
  • Since that date, the United States has observed a moratorium on explosive nuclear testing while maintaining its arsenal through non-explosive “stockpile stewardship” programs.

Context and “latest news”

  • The United States signed the Comprehensive Nuclear-Test-Ban Treaty (CTBT) in 1996 but has not ratified it; nonetheless, the test moratorium has remained in place through early 2026.
  • Policy debates periodically resurface in Washington about whether to resume testing, usually tied to concerns over warhead reliability or great-power competition, but no new U.S. nuclear test has been carried out since 1992.

In short, when people ask “when was the last US nuclear test,” the answer is: September 23, 1992, and it has remained the last one for more than three decades.

Information gathered from public forums or data available on the internet and portrayed here.