In the Fallout universe, the bombs fell during the event known as the Great War on October 23, 2077, with the first nuclear detonations hitting the United States at about 9:42 in the morning (Eastern time).

Core date and time

  • The Great War begins and ends on a single day: October 23, 2077.
  • Canon sources and franchise articles agree that the first strikes against the U.S. occur at roughly 9:42 am on the East Coast, with follow‑up detonations shortly after.
  • The active exchange lasts only around two hours before large‑scale conflict effectively ceases.

How this appears in games and TV

  • Multiple games (like Fallout: New Vegas and Fallout 4) reference October 23, 2077 as the day civilization was effectively destroyed, which later became known among fans as “Fallout Day.”
  • Franchise coverage and fan discussions note specific times such as 9:42 am for initial hits (e.g., Pennsylvania and New York) and slightly later strikes on places like Washington, D.C. and Boston.

East vs. West Coast timing

  • Lore discussions point out that 9:42 am Eastern would be very early morning on the U.S. West Coast (around 6:42 am Pacific), which can clash a bit with how some scenes in the TV show visually depict California getting hit closer to mid‑morning.
  • Fans often treat this as a minor inconsistency between strict in‑universe timestamps and cinematic presentation, but the accepted “answer” remains: bombs fall on Saturday, October 23, 2077, starting at about 9:42 am Eastern.

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