A referendum on the future of the Soviet Union was held on 17 March 1991 across the Soviet Union. It was the only national referendum in the history of the Soviet Union,[1] although it was boycotted by authorities in six of the fifteen Soviet republics.

The referendum asked whether to approve a new Union Treaty among the republics, to replace the 1922 treaty that created the USSR. The question put to most voters was:

Do you consider necessary the preservation of the Union of Soviet Socialist Republics as a renewed federation of equal sovereign republics in which the rights and freedom of an individual of any ethnicity will be fully guaranteed?

The referendum's question was approved by nearly 80% of voters in all nine other republics that took part. However, the August coup attempt by hardliners of the Communist Party prevented the anticipated signing of the New Union Treaty that was due to take place the next day.

Although it failed, the coup attempt reduced confidence in Gorbachev's central government. It was followed by a series of referendums for independence in individual republics and led to the dissolution of the Soviet Union on 26 December 1991.