Portsmouth South
Westminster constituency · England · South East
Forecast of October 15, 2026
Our forecast gives Labour a more than 99% chance of winning, with an average lead of 13.6 points.
Safe seat. Chance of a final gap under 5 points: under 1%.
Compared with the average
| Labour | Reform UK | Green | Conservative | |
|---|---|---|---|---|
| Portsmouth South | 36.7% | 23.1% | 12.8% | 12.5% |
| National averageUnited Kingdom | 24.3%+12.4 | 23.1% | 10.4%+2.4 | 20.4%−8.0 |
Simple average of the 650 ridings, not weighted by population.
Local profile
| Population | 107,571 |
|---|---|
| Median age | 33 |
| Employment rate | 75.6% |
Current member
Stephen Morgan · Labour
Previous election (2024)
Labour won by 33.8 points.
Our current projection: Labour ahead by 13.6 points.
Candidates and votes in 2024
| Candidate | Party | Votes | % |
|---|---|---|---|
| Stephen Morgan Elected | Labour | 18,857 | 48.4 |
| Mark Zimmer | Reform UK | 5,702 | 14.6 |
| Signe Biddle | Conservative | 5,643 | 14.5 |
| Charlie Murphy | Lib Dems | 4,886 | 12.6 |
| Elliott Lee | Green | 3,107 | 8.0 |
| Jacob Short | Other | 733 | 1.9 |
Nearby ridings
Party ahead and how sure the projection is.
- Portsmouth North Reform UK, toss-up
- Havant Reform UK, toss-up
- Gosport Conservative, safe seat
- Fareham and Waterlooville Conservative, toss-up
- Isle of Wight East Reform UK, toss-up
- Chichester Lib Dems, safe seat
Watch list
The tightest races
The smallest projected gaps between the top two.
- Forecast updated