The 1943 Christchurch East by-election held on 6 February was caused by the death of Tim Armstrong during the term of the 26th New Zealand Parliament. The by-election in the Christchurch East electorate was contested by five candidates, including representatives from the Labour Party, the Labour breakaway party Democratic Labour Party and the National Party. The election was won by the Labour candidate, Mabel Howard, and started her long parliamentary career, which included her becoming the first female cabinet minister in 1947.