1975 United Kingdom European Communities membership referendum
The United Kingdom European Communities membership referendum, also known variously as the Referendum on the European Community (Common Market), the Common Market referendum and EEC membership referendum, took place under the provisions of the Referendum Act 1975 on 5 June 1975 in the United Kingdom to gauge support for the country's continued membership of the European Communities (EC) — often known at the time as the European Community and the Common Market — which it had entered two-and-a-half years earlier on 1 January 1973 under the Conservative government of Edward Heath. The Labour Party's manifesto for the October 1974 general election had promised that the people would decide through the ballot box whether to remain in the EC.