The by-election was held on 7 February 1942 after the death of Lt-Col John Manchester Allen a National MP on 28 November 1941 while serving with the New Zealand Army in the Middle East (Libya).

[3] He was a candidate at the recent Waitemata by-election six months earlier, where he gained minimal support, polling just 88 votes.

The date for the by-election(s) was a problem because of the post-Christmas break and because of the arrangements required for voting by servicemen overseas.

Two by-elections were held on 7 February 1943 for Hauraki and Temuka where two independent candidates stood, but in Mid-Canterbury the widow of the sitting member was unopposed.

They were all National seats, and the Labour Party did not contest these wartime elections, but as independent candidates stood in two electorates, two by-elections were required.