How a UK general election works
The UK general election is really 650 separate constituency contests held on the same day. Each constituency elects one MP to the House of Commons, and voters choose between the candidates standing locally. There is no separate nationwide ballot for a party or for Prime Minister.
Each seat uses First Past the Post: the candidate with the most votes wins, even if they receive less than half of all votes cast in that constituency. Because seats are decided individually, a party’s share of the national vote does not translate directly into the same share of Commons seats. Where support is concentrated geographically — and how efficiently votes are distributed between constituencies — can make a substantial difference.
This is why marginal seats matter. At the 2024 general election, 115 constituencies were won by a margin of 5% or less of votes cast, and 46 were decided by less than 2%. The closest contests can therefore be determined by very small numbers of votes even when the national result looks much clearer.
Turnout also varies considerably. Across the UK, 59.7% of the electorate voted in 2024, the lowest general election turnout since 2001. At constituency level it ranged from 40.0% in Manchester Rusholme to 75.2% in Harpenden and Berkhamsted. That variation is another reason national percentages do not tell the whole story.
Voters elect their local MP; they do not directly elect the Prime Minister. A party that can command the confidence of the House of Commons can form a government. If no party wins a majority of seats, there is a hung Parliament. The existing Prime Minister remains in office initially while it becomes clear who can command Commons confidence; this can result in a minority government, an agreement with other parties or a formal coalition.
After polls close, votes are counted and the result is declared separately in each constituency. Once the new Parliament assembles, MPs elect a Speaker and are sworn in. The State Opening and King’s Speech then begin the new parliamentary session.