Elections and voting

Elections and voting

Find out more about how Members of Parliament are elected to the House of Commons in general elections and by-elections, the expected timetable for the general election on 7 May 2015 and the oath or affirmation taken by Members of the Commons and the House of Lords before they take their seats.

General elections

When Parliament is dissolved every seat in the House of Commons becomes vacant and a general election is held.


A by-election takes place when a seat in the House of Commons becomes vacant between general elections.

Parliamentary constituencies

The UK is currently divided into 650 parliamentary constituencies, each of which is represented by one MP in the House of Commons.

Swearing in and the parliamentary oath

Members of both the Commons and Lords have to take an oath of allegiance to the Crown when they take their seat in Parliament, or after the death of the monarch.

Voting systems in the UK

The House of Commons, devolved assemblies and mayors in the UK are elected using different voting systems. The Commons and the House of Lords also use a variety of voting systems for internal elections.

Are you registered to vote?

The general election will take place on Thursday 7 May 2015. To vote in an election you must be on the electoral register. You can register online or by post.

Electoral Commission

The Electoral Commission is an independent body, accountable directly to the UK Parliament, that regulates elections in the UK, promotes voter awareness and works to build confidence in the electoral process.

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