This is an annotated list of notable records from United Kingdom elections to the European Parliament, which were held from 1979 through 2019.
From 1979 until 1994, elections were conducted using first past the post (FPTP), with Great Britain divided into numerous single member constituencies.
From 1999 through 2019, however, mainland elections used the d'Hondt method of proportional representation (PR), with 11 multi-member constituencies corresponding to Scotland, Wales and the regions of England.
As a result, comparisons between these two types elections are problematic, and the voting system will be noted by each record.
After the introduction of PR, the number of seats correlated closely with national vote share, and no party ever won a majority.