The Louth by-election, 1969 was a by-election held on 4 December 1969 for the British House of Commons constituency of Louth in Lincolnshire.
The seat had become vacant on the death on 31 August of the Conservative Member of Parliament (MP) Sir Cyril Osborne. He had held the seat since the 1945 general election.
The result was a victory for the Conservative candidate Jeffrey Archer. He held the seat until he stepped down at the October 1974 general election, due to financial difficulties and turned to writing paperback novels.