The House of Commons
The nutshell
The House of Commons is the part of Parliament that voters choose. It has 650 members, called MPs. The Commons makes most new laws and checks the work of the government.
Every fact on this page comes from official guides to Parliament and non-partisan explainers. Each source tag — like EC — opens where a fact comes from.
The basics
What the House of Commons is
The House of Commons is the elected part of Parliament. The UK is split into 650 areas calledconstituencies. Voters in each constituency choose one Member of Parliament, or MP, so the Commons has 650 MPs.EC
What the Commons does
The main job of the Commons is to make laws. MPs debate and vote on new laws, called bills. The Commons also checks the work of the government by asking ministers questions. And only the Commons can let the government raise taxes.Parl
The Commons and the government
A government must keep the support of the Commons to stay in charge. This support is calledconfidence. The Institute for Government explains that a government holds office only while it commands the confidence of the Commons, and that the Commons can remove a government from office.IfG
How many MPs there are
The Commons has 650 MPs today. The House of Commons Library records that this number was set in 2010, and that the size of the Commons has changed many times since 1801.HoC
- Every one of the 650 MPs is elected by voters in one local area, called a constituency, according to the Electoral Commission
- The Commons alone decides money bills, such as new taxes, according to UK Parliament
- A government stays in office only while it keeps the confidence of the Commons, the Institute for Government notes
- The House of Commons is elected, but the House of Lords is not
- MPs are picked by first past the post, not by the share of votes each party wins across the UK, the Electoral Commission explains
- The number of MPs is set at 650 today, but it has changed many times since 1801, the House of Commons Library records
The deep end6 min
The elected chamber
Parliament has two chambers, or parts. The House of Commons is the elected one. The UK is divided into 650 constituencies, and voters in each one elect a single MP by first past the post — the candidate with the most votes wins the seat.EC Unlike the Commons, members of the House of Lords are not elected by voters.
Making laws, checking the government, and taxes
UK Parliament sets out three main roles for the Commons — debating and passing laws, examining the work of the government, and letting the government raise money through taxes.Parl Only the Commons can decide financial bills, such as new taxes. Government ministers answer MPs' questions in the Commons, and committees of MPs look in detail at each government department.
Why the government needs the Commons
A government stays in office only while it commands the confidence of the Commons, according to the Institute for Government, which quotes the Cabinet Manual. The Commons can hold the government to account, and it can ultimately remove a government from office.IfG A party with more than half of the 650 seats has a majority, which usually means it can win votes in the Commons.
A chamber that has changed size
The number of MPs is not fixed forever. The House of Commons Library records that the Commons had 658 seats in 1801, rose above 700 at times, and settled at 650 in 2010.HoC Boundary reviews can change where the lines between constituencies fall, and Parliament can change the total number of seats by law.