Heretaunga is a former New Zealand parliamentary electorate, in the city of Upper Hutt, that existed from 1954 until 1996.

The First Labour Government was defeated in the 1949 election and the incoming National Government changed the Electoral Act, with the electoral quota once again based on total population as opposed to qualified electors, and the tolerance was increased to 7.5% of the electoral quota. There was no adjustments in the number of electorates between the South and North Islands, but the law changes resulted in boundary adjustments to almost every electorate through the 1952 electoral redistribution; only five electorates were unaltered.^[1] Five electorates were reconstituted and the Heretaunga electorate was newly created, and a corresponding six electorates were abolished; all of these in the North Island.^[2] These changes took effect with the 1954 election.^[3]

The Heretaunga electorate was urban and was based on Heretaunga, a suburb of Upper Hutt in the northern Hutt Valley. Other places included Haywards and Birchville.^[4]

The electorate originated in 1954, and lasted to 1996, when with the introduction of MMP it was replaced by Rimutaka.

In the 1951 election, Upper Hutt had belonged to the Otaki electorate, and the National Party's incumbent Member of Parliament, Jimmy Maher had defeated the Labour' Party's candidate, Phil Holloway. In the 1954 election, Upper Hutt belonged to the newly-formed Heretaunga electorate, and Holloway stood against National's Allan McCready (Maher's son-in-law) and won decisively.^[5]

Up to 1990 when Peter McCardle won the seat for National, the Labour Party held Heretaunga. In 1993, McCardle narrowly held the seat against a challenge from Labour candidate Heather Simpson (who went on to become Helen Clark's Chief of Staff, known as H2 – Clark was H1^[6]). Subsequently, McCardle left the National Party in 1996 and joined New Zealand First.