An election to the 56th Parliament of the United Kingdom for the constituency area of Portsmouth South, held as part of the general election on 7 May 2015.
Conservative gain from Liberal Democrats by Flick Drummond with a majority of 5,241 - 12.5% - on a turnout of 58.5%.
Candidates
| Name | Party | Vote | Vote share | Vote change |
| DRUMMOND, Flick | Con | 14,585 | 34.8% | 1.6% |
| VERNON-JACKSON, Gerald | LD | 9,344 | 22.3% | -23.6% |
| CASTILLON, Sue | Lab | 8,184 | 19.5% | 5.9% |
| HARRIS, Steve | UKIP | 5,595 | 13.4% | 11.2% |
| MCCULLOCH, Ian | Green | 3,145 | 7.5% | 5.8% |
| HANCOCK, Mike | Ind | 716 | 1.7% | - |
| HOYLE, Sean | TUSC | 235 | 0.6% | - |
| JERRARD, Don | JACP | 99 | 0.2% | -0.0% |
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 71,639, having a valid vote count of 41,903 and an invalid vote count of 185.
Result declared at 06:11 on 8 May 2015.