An election to the 57th Parliament of the United Kingdom for the constituency area of South Northamptonshire, held as part of the general election on 8 June 2017.
Conservative hold by Andrea Leadsom with a majority of 22,840 - 35.1% - on a turnout of 75.8%.
Candidates
| Name | Party | Vote | Vote share | Vote change |
| LEADSOM, Andrea | Con | 40,599 | 62.5% | 2.3% |
| JOHNSON, Sophie | Lab | 17,759 | 27.3% | 10.6% |
| LOFTS, Chris | LD | 3,623 | 5.6% | -0.4% |
| WICKENS, Nigel | UKIP | 1,363 | 2.1% | -11.4% |
| DONALDSON, Denise | Green | 1,357 | 2.1% | -1.6% |
| PHILLIPS, Josh | Ind | 297 | 0.5% | - |
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 85,759, having a valid vote count of 64,998 and an invalid vote count of 125.
Result declared at 03:43 on 9 June 2017.