Beaconsfield by-election, 1982

The Beaconsfield by-election, 1982 was a parliamentary by-election held on 27 May 1982 for the British House of Commons constituency of Beaconsfield in Buckinghamshire. It is notable for being the only election Tony Blair lost in his 25-year political career. He was elected to parliament for Sedgefield, County Durham in the following year's general election, became party leader in 1994 and went on to become prime minister with three consecutive general election wins.

The seat had become vacant on 27 February 1982, when the constituency's Conservative Member of Parliament (MP), Sir Ronald Bell, died at the age of 67. He had been Beaconsfield's MP since the constituency was created for the February 1974 general election, having previously been MP for South Buckinghamshire since 1950. Bell had first entered Parliament at the Newport by-election in 1945, but lost that seat two months later at the 1945 general election.

The Conservative candidate was Tim Smith, who had been the surprise winner of the 1977 Ashfield by-election, where he overturned a Labour Party majority of nearly 23,000 votes. However, he lost the Ashfield at the 1979 general election, and was seeking to return to Parliament.