Heath joined the Civil Service in 1946, resigning a year later to pursue journalism and subsequently merchant banking. His political career began in 1950 when he was elected to Parliament, standing for Bexley, (Old Bexley, Sidcup after 1974).

He was named Assistant Opposition Whip in 1951 under Atlee, becoming Lord Commissioner of the Treasury when the Conservatives returned to power under Churchill. In 1952 he became Joint Deputy Chief Whip, in 1953 Deputy Chief Whip, and in 1955 Chief Whip and Parliamentary Secretary to the Treasury. In the Macmillian government (1959) he served as Minister of Labour and Lord Privy Seal (1960), speaking for the Government on foreign affairs. He was in charge of Britain's first application to join the European Community and was awarded the Charlemagne Prize recognizing his contribution toward promoting international co-operation. In 1963 under Douglas-Home, he was appointed Secretary of State for Industry, Trade and Development and president of the Board of Trade.

Heath became the first elected Leader of the Conservative Party while in Opposition in 1965, and succeeded Home as prime minister in 1970. In 1971, Britain signed the Treaty of Accession, joining the European Community. Heath was awarded the European Prize for Statesmanship. He was defeated in the general election of 1974, some think as a result of his opposition to striking minors as a tactic to keep inflation under control. After losing the second General Election of 1974 Heath was challenged and defeated by Margaret Thatcher who was initially viewed as a no hope "stalking horse" candidate. He was critical of Thatcher's policies especially her stand against full participation in the European Community.

Heath visited Mao-Tse Tung in China and served as a member of the Independent Commission of International Development Issues chaired by Herr Willy Brandt ( 1977-79).