Elections and voting

How are Members of Parliament elected to the House of Commons in general elections and by-elections? What was the timetable for the general election held on 8 June 2017?

What does the dissolution of Parliament mean for the House of Commons and the House of Lords? Why do MPs and members of the Lords take an oath of allegiance before they take their seats?

General elections

General elections

A general election is an opportunity for people in every part of the UK to choose their MP - the person who will represent their local area (constituency) in the House of Commons for up to five years.


A by-election occurs when a seat in the House of Commons becomes vacant between general elections, because the sitting MP dies, resigns or becomes ineligible to sit for some other reason.

Parliamentary constituencies

UK Parliamentary constituencies

The United Kingdom is currently divided into 650 parliamentary constituencies, each of which is represented by one Member of Parliament in the House of Commons.

Swearing in and the parliamentary oath

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

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 Lords also use a variety of voting systems for internal elections.

Brexit: research and analysis

Read research and analysis from Parliament's libraries and committees on how leaving the EU will affect different policy areas in the UK

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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