Notional results for a UK general election on 5 May 2005 By party
A notional general election to the 54th Parliament of the United Kingdom with an electorate of 40,611,844, having 24,814,623 valid votes.
| Party | Constituencies contested | Votes | Vote share | Constituencies won |
| Labour | 573 | 8,645,187 | 34.8% | 308 |
| Conservative | 573 | 8,412,809 | 33.9% | 209 |
| Liberal Democrat | 573 | 5,457,378 | 22.0% | 51 |
| Democratic Unionist Party | 18 | 241,856 | 1.0% | 9 |
| Sinn Féin | 18 | 174,530 | 0.7% | 5 |
| Social Democratic & Labour Party | 18 | 125,626 | 0.5% | 3 |
| Plaid Cymru | 40 | 174,838 | 0.7% | 2 |
| Ulster Unionist Party | 18 | 127,414 | 0.5% | 1 |
| Respect Party | 3 | 30,190 | 0.1% | 1 |
| Independent Kidderminster Hospital and Health Concern | 1 | 18,739 | 0.1% | 1 |
| UK Independence Party | 485 | 597,114 | 2.4% | 0 |
| Green Party | 190 | 257,654 | 1.0% | 0 |
| British National Party | 115 | 191,154 | 0.8% | 0 |
Estimates of the 2005 general election result in new constituencies
Colin Rallings and Michael Thrasher, then at the University of Plymouth, produced estimates of the 2005 general election result as if the new constituencies recommended by the separate Parliamentary Boundary Commissions for England, Wales and Northern Ireland had then been in existence.
The Elections Centre, established by Professors Colin Rallings and Michael Thrasher, moved to the University of Exeter in 2003.