Simulation · United Kingdom

UK Election Simulator

Model a Westminster general election: 650 constituencies, first-past-the-post, all four nations. Calibrated to the real 2024 result — then swing it however you like.

General Election — First Past the Post

650 seats · 326 to win

Set each party's national vote share, political position, and geographic spread. Each of the 650 seats starts from its 2024 baseline; your changes apply as proportional swing shaped by ideology and demographics (the Electoral Calculus approach). The winner in each seat takes it — no prizes for second.

Total: 0.0%

Pacts & Tactical Voting

Anti-split arithmetic

Under first-past-the-post, two parties splitting the same vote can lose seats both would win alone. Model the fix two ways: a formal stand-aside pact, where only the strongest partner contests each seat, or an informal tactical squeeze, where voters desert weaker partners only in seats that are genuinely winnable.

Transfers are never perfect: in a stand-aside pact the votes that don't transfer are treated as abstentions and drop out of the count, which is what usually happens when a party asks its supporters to back a rival.