Elections and voting

Find out more about general elections and by-elections to elect MPs and learn how different voting systems are used internally by the House of Commons and the House of Lords.

Voting systems in the UK

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

General elections

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

By-elections

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.

Related information

Constituency: This is a geographical area of the UK which is represented by one MP in the House of Commons.

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.

Electoral Commission

Parliament is not responsible for the content of external websites.

Related internet links

The following links are from the Electoral Commission website.

How do I vote?
Registering to vote

How do I become a candidate?
Standing as a candidate

Parliament is not responsible for the content of external websites.