Constituencies in the next United Kingdom general election

The boundary commissions in the United Kingdom are non-departmental public bodies responsible for determining the boundaries of constituencies for elections to the Westminster (UK) Parliament, the Scottish Parliament and the National Assembly for Wales. There are four separate boundary commissions:

Each commission comprises four members, three of whom take an active part in meetings. The Speaker of the House of Commons is ex officio chairman of each of the boundary commissions. The Speaker however does not play any part in proceedings, with a each boundary commission having a Justice being appointed as Deputy Chairman Commissioner.

The commissions are currently established under the Parliamentary Constituencies Act 1986, most recently amended by the Parliamentary Voting System and Constituencies Act 2011. They were first established as permanent bodies under the House of Commons (Redistribution of Seats) Act 1944. The 1944 Act was amended in 1947 and then replaced by the House of Commons (Redistribution of Seats) Act 1949. The 1949 Act was amended in 1958 and 1979 and replaced by the 1986 Act; changes in legislation from 1944 to 1986 were generally incremental in nature. The 2011 Act under the Con-LibDem coalition government made substantial changes to the legislation governing constituency boundary reviews.

The Political Parties, Elections and Referendums Act 2000 under PM Tony Blair's government envisaged that the functions of the boundary commissioners would be transferred to the United Kingdom Electoral Commission, but this never transpired: the Local Democracy, Economic Development and Construction Act 2009 repealed the Act of Parliament (of 2000) effective from 1 April 2010.

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