1966 United Kingdom general election

← 1964 31 March 1966 1970 →
← outgoing members elected members →
All 630 seats in the House of Commons 316 seats needed for a majority
Opinion polls
Turnout	75.8% (1.3 pp)
First party Second party Third party   Leader Harold Wilson Edward Heath Jo Grimond Party Labour Conservative Liberal Leader since 14 February 1963 28 July 1965 5 November 1956 Leader's seat Huyton Bexley Orkney and Shetland Last election 317 seats, 44.1% 304 seats, 43.4% 9 seats, 11.2% Seats won 364[note 1] 253 12 Seat change 47 51 3 Popular vote 13,096,951 11,418,433 2,327,533 Percentage 48.0% 41.9% 8.5% Swing 3.9% 1.5% 2.7%
Colours denote the winning party—as shown in § Results
Composition of the House of Commons after the election
Prime Minister before election Harold Wilson Labour Prime Minister after election Harold Wilson Labour

The 1966 United Kingdom general election was held on Thursday 31 March 1966. The result was a landslide victory for the Labour Party led by incumbent Prime Minister Harold Wilson.

Wilson decided to call a snap election since his government, elected a mere 17 months previously, in 1964, had an unworkably small majority of only four MPs. The Labour government was returned following this snap election with a much larger majority of 98 seats. This was the last British general election in which the voting age was 21; Wilson's government passed an amendment to the Representation of the People Act in 1969 to include eligibility to vote at age 18, which was in place for the next general election in 1970.

This was the only election between 1945 and 1997 in which the Labour Party won a workable majority sustainable to last a full term. In the next seven general elections, the Labour Party would win a majority of seats only once (October 1974) and would lose five elections to the Conservatives. This election also noted the Labour Party achieving its third-highest vote-share (48%) and second largest total number of votes in history (the largest vote-share being the 49.7% achieved in the 1945 election).

Prior to the 1966 general election, Labour had performed poorly in local elections in 1965, and lost a by-election, cutting their majority to just two. Shortly after the local elections, the leader of the Conservative Party Alec Douglas-Home was replaced by Edward Heath in the 1965 leadership election.

Despite setbacks and a small majority, Labour believed it had an advantage due to the disorientation from the change of leadership at the Conservative Party, the improvement of economic conditions under its brief government, and a victory at the 1966 Kingston upon Hull North by-election.^[1] The Conservatives had not had much time to prepare their campaign, although it was more professional than previously. There had been little time for Heath to become well known among the British public, having led the party for just eight months before the election. For the Liberal Party, money was an issue: two elections in the space of just two years had left the party in a tight financial position and had to field fewer candidates.^[2] Labour ran its campaign with the slogan "You know Labour government works" and avoided commenting on controversial issues such as European integration, trade unions, and nationalisation.^[1]

The election night was broadcast live on the BBC, was presented by Cliff Michelmore, Ian Trethowan, Robin Day, Robert McKenzie and David Butler. The election was replayed on the BBC Parliament channel on the 40th anniversary of the event,^[3] and again in 2016 to mark the 50th anniversary of the election.^[4]

Although the BBC's telecast was in black and white, a couple of colour television cameras were placed in the BBC election studio at Television Centre to allow CBS's Charles Collingwood and NBC's David Brinkley to file live reports from that studio by satellite and in colour for their respective networks' evening news programmes (which were transmitted at 11:30 pm British time, 6:30 pm Eastern Standard Time).

The Prime Minister, Harold Wilson, announced on 28 February that Parliament would be dissolved on 10 March, for an election to be held on 31 March. The key dates were as follows:

• Research Services: 3% swing to Labour (forecast majority of 101)
• National opinion polls: 3.5% swing to Labour (forecast majority of 115)
• Gallup: 4.5% swing to Labour (forecast majority of 150)
• Express (known as Harris): 7.5% swing to Labour (forecast majority of in excess of 255)

The Labour Party performed very well in the election and expanded its previously slim majority against the Conservative opposition to 97 seats, accomplishing a net gain of 48 seats. It won 364 seats from 48 per cent of the vote, against 253 seats from 41.4 per cent for the Conservatives and 12 seats from 8 per cent for the Liberals. A major reason for the Labour victory was the revitalization of the party's working-class support in the 1960s. It captured its highest support yet from manual laborers at 69 per cent, as well as its best performance for non-manual laborers since 1945. The government also appealed to both the right wing of the party with its cabinet dominated by junior ministers of the Attlee ministry as well as the left wing by the presence of officials such as Prime Minister Wilson, Richard Crossman, Barbara Castle, and Frank Cousins.^[1] Although the party would go on to win more seats under Tony Blair (1997, 2001) and Keir Starmer (2024), Labour have never since matched the 48% of the popular vote they won in 1966.

These declarations were covered live by the BBC where the returning officer was heard to say "duly elected".

• The 5,117 votes polled for the "Others" in Nelson and Colne were all polled for Patrick Downey, uncle of Lesley Ann Downey, who had been murdered by the Moors Murderers. Downey advocated the return of hanging.

• List of MPs elected in the 1966 United Kingdom general election
• 1966 United Kingdom general election in Northern Ireland

• Bromhead, Peter. "The General Election of 1966". Parliamentary Affairs 19.3 (1966): 332-345.

• Butler, David E., and Anthony King. The British General Election of 1966 (1966); the standard scholarly study.
• Craig, F. W. S. (1989), British Electoral Facts: 1832–1987, Dartmouth: Gower, ISBN 0900178302

• Kavanaugh, Dennis. "1966: An Opportunity Squandered" in Andrew S. Crines, and Kevin Hickson, eds. Harold Wilson: The Unprincipled Prime Minister?: A Reappraisal of Harold Wilson (Biteback Publishing, 2016) pp. 39-56.

• Pimlott, Ben. Harold Wilson (HarperCollins, 1992) pp.395-404.
• Schaffer, B.B. "The British General Election, 1964: A Retrospect", Australian Journal of Politics and History (1965) 11#1 pp. 7-22, doi:10.1111/j.1467-8497.1965.tb00411.x.

• United Kingdom election results—summary results 1885–1979 Archived 23 February 2008 at the Wayback Machine

• Action Not Words: The New Conservative Programme, 1966 Conservative Party manifesto
• Time for Decision, 1966 Labour Party manifesto
• For All the People: the Liberal Plan of 1966, 1966 Liberal Party manifesto