What is a by-election?

A by-election is held to fill a vacant electorate seat — for example, if a member of Parliament resigns or dies. A by-election is only open to voters who are enrolled in the electorate, and there is no party vote.

How a by-election is run

Just like a general election, a by-election has rules and timelines to follow. The voting period runs for about 2 weeks.

Here are the main steps in the by-election process.

A vacancy notice is published and the by-election date announced

The Speaker of the House of Representatives publishes a notice of the vacancy in the New Zealand Gazette (the official government newspaper).

View a vacancy notice in the Gazette

The Prime Minister will decide the by-election date and announce it. 

Governor-General tells the Chief Electoral Officer to run a by-election

Within 21 days of the vacancy notice being published, the Governor-General issues a ‘writ’ (a written notice) directing the Chief Electoral Officer to conduct a by-election in the electorate. 

The writ includes:

  • by-election date
  • closing date for candidates to be nominated
  • latest date for the writ to be returned with the name of the elected candidate.

Candidates are nominated

During this stage, candidates can be nominated to contest the by-election.

To contest a by-election, a candidate must be:

  • a New Zealand citizen
  • enrolled to vote
  • nominated by two people enrolled in the electorate where the by-election is being held. 

A candidate can stand on behalf of a political party or as an independent. 

By-election is held and final results are published

During a by-election, voting places open across the electorate. Only people enrolled in the electorate can vote for their preferred candidate. 

When the voting period ends, votes are counted and the final results are published. The candidate with the most votes becomes the elected member of Parliament for that electorate. 

When a by-election will not be held

A by-election will not happen in the following situations:

  • the vacancy happens within 6 months of Parliament’s 3-year term ending
  • the Prime Minister informs the House of Representatives that a general election will be held within 6 months of the vacancy.

In both of these situations, at least 75% of the members of Parliament must agree that the vacancy will not be filled. 

How a by-election can change the make-up of Parliament

A by-election result can change:

  • the proportionality of Parliament
  • the number of MPs a party has in Parliament.

For example, a by-election might be won by a candidate who represents a different party from that of the MP who has left.  

A by-election does not affect the number of list seats each party is entitled to — list seats are not recalculated after a by-election. 

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