On what date did Japan's Instrument of Surrender take effect in World War II?

Japan's Instrument of Surrender took effect on September 2, 1945, formally ending World War II hostilities with Japan.

The document was signed that morning aboard the USS Missouri in Tokyo Bay. The ceremony began shortly after 9:00 a.m. Japan Standard Time and concluded at 9:25 a.m. The agreement recorded Japan's acceptance of the terms set by the Allied powers.

Japan had announced its decision to surrender in August, but the August announcement and the September ceremony were different events. August 15 is commonly called V-J Day in several countries because it marked the public announcement or effective cessation of fighting, while September 2 marks the formal signing.

Representatives of Japan and nine Allied nations signed the instrument. The ceremony's location, date, and written agreement made September 2 the clearest legal and diplomatic endpoint of the Pacific War.