At what time did Japan’s surrender officially take effect during the 1945 ceremony?

Japan’s surrender officially took effect at 9:25 a.m. Japan Standard Time on September 2, 1945.

The ceremony began shortly after 9 a.m. on USS Missouri in Tokyo Bay. Japanese representatives signed first, followed by General Douglas MacArthur and representatives of the Allied governments. After the final signatures and closing remarks, the surrender became effective at 9:25 a.m.

This precise time is different from the noon broadcast on August 15, when Hirohito announced Japan’s acceptance of the Potsdam Declaration. The two moments are linked but are not identical: the broadcast communicated the decision, while the signed instrument formalized it.

The timing also explains why historical accounts use more than one V-J Day date. August 15 is widely associated with the public announcement, while September 2 is associated with the legal ceremony and formal conclusion.