Below are lists of Reform UK marginal seats showing which constituencies won in the latest elections can be most easily lost.
Historical
Below is the Reform UK defence list consisting of Reform UK held marginal seats for the 2029 general election based on the 2024 boundaries. These marginal constituencies are ordered from the most vulnerable seats to the safest.
| Rank | Constituency | Region | Majority | Swing to Defeat | |
|---|---|---|---|---|---|
| 1. | Basildon South and Thurrock East | East of England | 98 | 0.12% | |
| 2. | Great Yarmouth | East of England | 1,426 | 1.75% | |
| 3. | Boston and Skegness | East Midlands | 2,010 | 2.48% | |
| 4. | Ashfield | East Midlands | 5,508 | 6.91% | |
| 5. | Clacton | East of England | 8,405 | 9.14% |