The Treaty of Westminster of 1674 was the peace treaty that ended the Third Anglo-Dutch War. Signed by the Dutch Republic and the Kingdom of England, the treaty provided for the return of the colony of New Netherland (now New York) to England and renewed the Treaty of Breda of 1667. The treaty also provided for a mixed commission for the regulation of commerce, particularly in the East Indies.

It was signed on 19 February 1674 Old Style (9 February 1674 New Style) by Charles II of England and ratified by the States General of the Netherlands on 5 March 1674. England was forced to sign the treaty since Parliament would not allow more money to be spent on the war and had become aware of the secret Treaty of Dover in which Charles had promised Louis XIV of France to convert to Catholicism at an opportune moment. The English were dismayed by the unexpected fact that Dutch raiders had managed to capture more English ships than vice versa and that New Amsterdam had been retaken by the Dutch in 1673.