Below are lists of Sinn Fein marginal seats showing which constituencies won in the latest elections can be most easily lost.
Below is the Sinn Fein defence list consisting of Sinn Fein held marginal seats for the 2025 general election. These marginal constituencies are ordered from the smallest to the largest swing to be defeated by the largest opposition party.
View Sinn Fein target seats for the next general election.
(order by percentage majority)
| Rank | Constituency | Region | Majority | Swing to Defeat | |
|---|---|---|---|---|---|
| 1. | Fermanagh and South Tyrone | Northern Ireland | 57 | 0.06% | |
| 2. | Down South | Northern Ireland | 1,620 | 1.63% | |
| 3. | Belfast North | Northern Ireland | 1,943 | 1.98% | |
| 4. | Tyrone West | Northern Ireland | 7,478 | 9.08% | |
| 5. | Newry and Armagh | Northern Ireland | 9,287 | 9.14% | |
| 6. | Ulster Mid | Northern Ireland | 9,537 | 10.69% | |
| 7. | Belfast West | Northern Ireland | 14,672 | 18.92% |
View Sinn Fein target seats for the next general election.
