List of marginal seats before the 2024 United Kingdom general election

The 2024 United Kingdom general election was held on 4 July 2024. These were the target seats for each of the political parties, according to notional results from the previous election in 2019. These marginal seats are listed by notional swing required for each party to gain the seat. They are not necessarily the seats that the parties are choosing to target.

Owing to boundary changes following the 2023 Periodic Review of Westminster constituencies, these target seats are determined by notional results of the previous election using the new constituencies as if they were contested in 2019.

Reform UK
The target seats for Reform UK are based on results of the Brexit Party in 2019. The party didn't contest Conservative-held seats so their target seats based on the 2019 result are primarily in North East England and Wales.

Northern Ireland parties
Target seats requiring swings of under 10%: