The Mechanics of FPTP Distortion
First Past the Post does not distribute seats based on national vote totals. Each of the UK’s 650 constituencies is an entirely separate election, won by the candidate with the most local votes regardless of margin. This means national vote share can be almost entirely disconnected from seat share.
The critical variable is geographic concentration. A party whose voters are clustered in specific areas will win those areas outright. A party whose voters are spread evenly across every constituency will come second or third everywhere and win almost nothing.
2024: The Full Seat Distortion Table
| Party |
Votes |
Vote % |
Actual Seats |
PR Seats* |
Votes/Seat |
| Labour | 9,708,716 | 33.7% | 412 | 219 (-193) | 23,614 |
| Conservatives | 6,828,925 | 23.7% | 121 | 154 (+33) | 56,437 |
| Reform UK | 4,117,221 | 14.3% | 5 | 93 (+88) | 823,444 |
| Lib Dems | 3,519,199 | 12.2% | 72 | 79 (+7) | 48,878 |
| Greens | 1,944,501 | 6.7% | 4 | 43 (+39) | 486,125 |
| SNP | 724,758 | 2.5% | 9 | 16 (+7) | 80,529 |
| Plaid Cymru | 194,811 | 0.7% | 4 | 4 (0) | 48,703 |
*PR seats calculated as: vote share × 650. Green/red figures show seat gain vs actual. Sources: Electoral Commission 2024.
Why Reform UK Were So Hard Hit
Reform UK’s vote is highly dispersed. Nigel Farage’s party polled 14%+ in virtually every English constituency — but rarely won any of them outright. Coming second in 400 constituencies counts for exactly zero seats under FPTP.
The Lib Dems, by contrast, have concentrated their vote in specific seats — particularly in southern England and the so-called “Blue Wall” former Tory seats. They won 72 seats on 12.2% of the vote because those votes were placed efficiently in winnable constituencies.
Reform UK 2024
4.1m votes
= 5 seats
Vote spread: even across England. Rarely won any single seat outright despite polling 20%+ in some areas.
Lib Dems 2024
3.5m votes
= 72 seats
Vote concentration: targeted campaign in formerly safe Tory seats. Concentrated tactical support turned plurality into wins.
What 2026 Polling Means Under FPTP
With Reform UK polling at 26% nationally in 2026 — up from 14.3% in 2024 — the question is whether they can convert that into seats. Under FPTP, the answer depends almost entirely on whether their vote becomes geographically concentrated.
MRP models in 2026 suggest Reform could win 80–120 seats at current polling levels if their vote concentrates in Leave-heavy, working-class constituencies. But if it remains dispersed, they could hit 26% nationally and still win fewer than 30 seats.
The FPTP Paradox for Reform UK
Reform UK simultaneously benefit from FPTP criticism (arguing the system is unfair to them) and would likely be hurt by PR if it led to a permanent Lab-LD or Labour majority coalition. Their electoral incentives are contradictory, which explains their official opposition to electoral reform despite being its biggest current victim.
Disproportionality Over Time
The 2024 election was not an outlier — it was the worst example of a consistent pattern. The Gallagher Index (which measures electoral disproportionality) showed 2024 as the highest in UK electoral history.
| Election | Winner | Vote % | Seat % | Seat Bonus |
|---|
| 2024 | Labour | 33.7% | 63.4% | +29.7pp |
| 2019 | Conservatives | 43.6% | 56.2% | +12.6pp |
| 2017 | Conservatives | 42.3% | 48.9% | +6.6pp |
| 2015 | Conservatives | 36.9% | 50.9% | +14.0pp |
| 2010 | Conservatives | 36.1% | 47.1% | +11.0pp |
| 2005 | Labour | 35.2% | 55.1% | +19.9pp |
| 2001 | Labour | 40.7% | 62.5% | +21.8pp |
| 1997 | Labour | 43.2% | 63.4% | +20.2pp |