UK Politics Simulator models elections at both Westminster and local government level. This page explains how the election system works.
General elections contest all 650 parliamentary constituencies simultaneously. They occur at least every five years, though the Prime Minister can call one earlier. Results determine which party (or coalition) forms the government.
Parliamentary by-elections fill single-seat vacancies caused by an MP's death, resignation, or removal. They follow the same voting rules as general elections but typically see lower turnout and often swing against the governing party.
Council elections vary by council type:
Council by-elections fill single vacancies in individual wards. Only one seat is contested regardless of how many seats the ward normally has.
England and Wales use First Past the Post (FPTP) for all elections. In multi-member council wards, this becomes block voting: voters can vote for as many candidates as there are seats, and the top vote-getters win.
Scotland and Northern Ireland use Single Transferable Vote (PR-STV) for local elections. Voters rank candidates by preference. Seats are allocated proportionally using a quota system with vote transfers.
Results are calculated from multiple inputs:
Each ward and constituency has a demographic profile based on real census data, including:
These demographics influence baseline party support. Different demographic groups have different voting tendencies, and those tendencies are modelled per policy area, not as a single "left-right" preference.
National polling provides a baseline. If a party is polling 10 points higher nationally than at the last election, that swing filters down to local contests. However, local results vary from the national picture based on:
The simulation models tactical voting in marginal seats:
In local elections especially, individual candidates can outperform or underperform their party's baseline. Factors include:
The personal vote effect is stronger in council elections (where wards are smaller and candidates more visible) than in parliamentary elections.
Campaign activity influences results within bounds.
Campaign impact is capped. In council elections, the maximum swing from campaigning is approximately 15 percentage points. In general elections, the ceiling is lower (around 10 points). Effective campaigning matters in marginal seats but cannot overcome a fundamental mismatch between candidate and constituency.
Smaller wards are more responsive to campaign activity. A candidate who knocks on 500 doors in a 3,000-electorate ward has contacted a much larger share than the same effort in a 7,000-electorate ward.
Election night proceeds in real time (compressed).
You do not see your own result until it is declared. Close races create uncertainty until the announcement.
If one party wins 326+ seats, they form a majority government.
If no party reaches 326, a hung parliament results. Possible outcomes:
Coalition viability depends on seat arithmetic, ideological compatibility, and policy red lines.
Similar dynamics apply at council level. Councils frequently have no overall control (NOC), leading to coalition or minority administrations. Council control affects what the local authority can achieve and how stable the administration is.
For specific questions about election mechanics, see FAQs.