First Past the Post (FPTP) is the electoral system used to elect MPs to the House of Commons. It is simple at constituency level: the candidate with the most votes wins.
How it works
Each parliamentary constituency elects one MP. Voters choose one candidate. Once the ballots are counted, whoever has more votes than any other candidate is elected — even if that candidate has less than half of all votes cast.
There is therefore no requirement for a winning candidate to secure an absolute majority of the constituency vote.
Why vote share and seat share differ
The national result is the sum of 650 local contests. Seats are not allocated according to national vote share. Where a party’s support is located can therefore matter as much as its total number of votes.
In 2024, for example, Labour received 33.7% of the UK vote and won 63.2% of Commons seats. Reform UK received 14.3% of votes and 0.8% of seats, while the Liberal Democrats received 12.2% of votes and 11.1% of seats. These figures describe the result rather than judging the electoral system.
Concentrated and dispersed support
A party can win seats efficiently if its votes are concentrated in constituencies where it can finish first. Conversely, large numbers of votes in seats it does not win — or very large majorities in seats it already wins comfortably — do not produce additional MPs.
Is FPTP proportional?
No. FPTP is a plurality system, not a proportional representation system. Its purpose is to select one winner in each constituency rather than make national seat totals proportional to national votes.
Where is it used?
FPTP is used for elections to the House of Commons. Other elections in the UK use different systems, including the Additional Member System for the Scottish Parliament, STV for the Northern Ireland Assembly and a closed-list proportional system for the Senedd.
Sources and further reading
Electoral Commission: How votes are counted ↗ · Commons Library: Voting systems in the UK ↗