The 1973 Thamesdown Borough Council election took place on 7 June 1973 to elect members of Thamesdown Borough Council, a predecessor to Swindon Borough Council in Swindon, Wiltshire, England. It was the first election to the district council, although it acted as a "shadow authority" until 1 April 1974, where it gained full responsibilities as laid out in the Local Government Act 1972.
The whole council was up for election, and Labour gained a majority, winning 26 out of 46 seats on the council.