The winners

The major winners of the 2015 were clearly the Conservatives, who won 50.9% of seats in parliament on the basis of 36.8% of the vote. Labour were also notable beneficiaries of FPTP; winning 35.7% of seats in parliament but 30.4% of votes. The Scottish National Party (SNP) also benefit significantly from FPTP; winning 8.6% of seats, while attracting only 4.7% of votes.

The losers

It is immediately clear that voters for the UK Independence Party (UKIP) lost out significantly in 2015. UKIP garnered 12.6% of the vote but were rewarded with only 1 seat in parliament (out of 650). The Liberal Democrats (Lib Dems) and Green Party Of England and Wales (Greens) also did not win numbers of seats reflective of their support level, winning 7.9% and 3.6% of the vote, respectively, but only 1.2% and 0.2% of seats.

The winners

Once again, the Conservatives and SNP were over-represented in parliament relative to their shar of the vote, winning 48.9% and 5.4% of seats on 42.4% and 3.0% of the vote, respectively. Their over-representation was not as exaggerated as in 2015 and resulted in a minority Conservative governemnt, propped up by the Democratic Unionist Party (DUP), who also were slightly overrepresented by their 1.5% share of seats in parliament, relative to their 0.9% vote share.

The losers

In 2017 Labour did not benefit from FPTP, winning 40.3% of seats on 40.0% of the vote. The Lib Dems, Greens and UKIP lost out again, each winning fractions of the available seats well below the fraction of the vote they accounted for. Indeed, despite winning 594,068 votes (or 1.8% of 32,169,920 total), UKIP won no seats this year.

The winners

The Conservatives and SNP remained the greatest beneficiaries of FPTP, with 43.6% and 3.9% of the vote resulting in 56.2% and 7.4% of seats for them, respectively.

The losers

In 2019 Labour joined the ranks of the underrepresented parties, with 32.2% of the vote returning a 31.2% share of seats. They joined the Lib Dems and Greens in winning seats numbers (1.7% and 0.2%, respectively) unaligned to their vote share (11.5% and 2.7%, respectively). The UKIP vote evaporated in 2019 but many of its voters may have been among the 644,257(2% of the total) voting for the Brexit Party but not gaining a single seat.