Multi-member constituencies in the Parliament of the United Kingdom

Multi-member constituencies in the UK Parliament (and its predecessor bodies in the component parts of the United Kingdom) existed from the earliest era of elected representation in Parliament until the last of them were abolished prior to the United Kingdom general election, 1950, with the passing of the Representation of the People Act 1948. Since 1950, all members of the United Kingdom House of Commons have been elected from single member constituencies.

Three electoral systems have been used to return multiple members to Parliament.

The original method and the one most commonly used was the bloc vote.

In multi-member elections under this system, electors could cast a vote for up to as many candidates as there were seats to be filled. The elector could not vote more than once for any candidate, but was free not to use all the possible votes. A single vote for only one of the candidates was known as a plumper, and was particularly valued by politicians.

At the close of the poll the leading candidates, with the largest number of votes (to the required number to fill the vacant seats), were declared elected.

This was a non-proportional election system, so it suffered from the defect that an elector using all his votes might contribute to the defeat of the candidate he most preferred. It also was not a system which guaranteed minority representation, as a majority which voted solidly for candidates of one party could win all the seats.

An advantage of the system, at least from the point of view of politicians, was that it enabled different sections of a party or allied groups to work together in the same constituency. In the early and mid-19th century it was quite common for liberals in an area with two seats to support a left wing liberal Radical candidate and a right wing liberal Whig nominee. Similarly in the early 20th century the Liberal Party and Labour Party found it easier to split the seats in the remaining two member constituencies than to share out single member divisions.

In 1868, the limited vote was introduced, which was similar to the bloc vote but restricted an individual elector in a three or four seat constituency to using up to one fewer vote than the number of seats to be filled.

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