List of political parties in New Zealand

New Zealand national politics feature a pervasive party system. Usually, all members of Parliament's unicameral House of Representatives belong to a political party. Independent MPs occur relatively rarely. While two primary parties do indeed dominate the political landscape, the country now more closely resembles a multi-party state, where smaller groups can reasonably expect to play a role in government. As of March 2017, seven parties have representatives in Parliament.

Political parties in New Zealand evolved towards the end of the nineteenth century out of interest groups and personal cliques. Most historians regard the Liberal Party, which began its rule in 1891, as the first real party in New Zealand politics. During the long period of Liberal Party control the party's more conservative opponents founded the Reform Party, forming the original duopoly in the New Zealand parliament.

Gradually, Liberal and Reform found themselves working together more often, mostly in opposition to the growing Labour Party. After Labour eventually won office in 1935, the Liberals (now known as the United Party) and Reform came together in 1936 to form the National Party. Labour and National currently exist as the two main parties of New Zealand politics.

Over the years, a number of "third parties" or so-called "minor parties" developed, notably the Social Credit Party, the New Zealand Party, the Values Party, and the Alliance. However, the "first past the post" electoral system meant that regardless of how many votes a party gained nationwide, it could not win a seat without a plurality in a particular electorate (voting district). Under such conditions, these parties mostly performed poorly in terms of making an impact in Parliament.

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