Parliament facts
How many MPs are there? UK Parliament facts
The quick facts about the UK House of Commons — how many MPs and constituencies there are, how the seats are split between the parties, and how MPs vote. The figures below come straight from the data we track, so they update as Parliament changes.
650
Seats in the Commons
649
Sitting MPs
1 vacant
17
Parties represented
2,333
Divisions tracked
to 17 Jun 2026
Seats by party
How the 650 seats are currently held. Labour is the largest party with 403 seats — an overall majority.
See the full parties directory or how the parties have changed over time.
A few more facts
Each MP represents one constituency and is elected at a general election, held at least every five years. Between elections, a seat can change hands at a by-election if it falls vacant. We are tracking 1,070,386 individual MP votes across 2,333 recorded Commons divisions.
Curious where your own MP stands? Find out who your MP is, how they voted, or how much MPs are paid.
Common questions
How many MPs are there in the UK?
There are 650 seats in the House of Commons — one Member of Parliament for each constituency. We currently hold records for 649 sitting MPs, with 1 seat vacant pending a by-election.
How many constituencies are there in the UK?
There are 650 parliamentary constituencies, each electing one MP to the House of Commons. The current boundaries were used for the 2024 general election.
What is a majority in the House of Commons?
A party has an overall majority when it holds more than half of the 650 seats — that is, at least 326. The largest party, Labour, currently holds 403 seats, an overall majority.
Which party has the most MPs?
Labour is currently the largest party in the House of Commons, holding 403 of the 650 seats (62%).
How does the House of Commons vote?
When MPs vote, they hold a 'division': MPs walk through the 'Aye' (yes) or 'No' lobby and their names are recorded. Whichever side has more votes wins. This is why a name-by-name record of every MP's vote exists.