An election to the 56th Parliament of the United Kingdom for the constituency area of St Ives, held as part of the general election on 7 May 2015.
Conservative gain from Liberal Democrats by Derek Thomas with a majority of 2,469 - 5.1% - on a turnout of 73.7%.
Candidates
| Name | Party | Vote | Vote share | Vote change |
| THOMAS, Derek | Con | 18,491 | 38.3% | -0.7% |
| GEORGE, Andrew | LD | 16,022 | 33.2% | -9.6% |
| CALDERWOOD, Graham | UKIP | 5,720 | 11.8% | 6.3% |
| OLIVIER, Cornelius | Lab | 4,510 | 9.3% | 1.2% |
| ANDREWES, Tim | Green | 3,051 | 6.3% | 3.5% |
| SIMMONS, Rob | MK | 518 | 1.1% | 0.2% |
Under section 13(b) of the Representation of the People Act 1985, a candidate gaining 5% or less of the vote share will forfeit their deposit.
An electorate of 65,570, having a valid vote count of 48,312 and an invalid vote count of 78.
Result declared at 15:26 on 8 May 2015.