These seats are where the winning party is forecast to gain the narrowest lead over the third-place party, according to VoteClimate's Forecast For The Next General Election.

These are seats where Registering with VoteClimate will have the maximum influence on party policies. So if you have climate-concerned friends and family in these areas, please invite them to join us!

If VoteClimate can recruit one million members and they are distributed evenly across the UK, that's 2.1% of registered voters in each seat.

Vote shares (GB): Labour: 25.4% | Reform: 23.3% | Conservative: 19.9% | Green: 11.7% | Liberal Democrat: 10.4%

[Last updated: September 2026]

Constituency	Winner		Second		Third		Votes Required
Southend West and Leigh	Reform	12,708	Labour	12,683	Conservative	12,450	258	0.34%
Mid Derbyshire	Labour	13,155	Conservative	13,032	Reform	12,856	299	0.43%
North East Hertfordshire	Labour	13,963	Conservative	13,887	Reform	13,447	516	0.66%
Pendle and Clitheroe	Conservative	12,772	Reform	12,539	Labour	12,177	595	0.76%
Bracknell	Conservative	11,820	Reform	11,611	Labour	11,235	585	0.82%
Suffolk Coastal	Reform	12,468	Conservative	12,268	Labour	11,852	616	0.83%
Bury St Edmunds and Stowmarket	Reform	13,240	Conservative	12,731	Labour	12,547	693	0.88%
Aylesbury	Conservative	12,234	Labour	11,492	Reform	11,461	773	0.98%
South Dorset	Reform	12,831	Conservative	12,345	Labour	11,909	922	1.21%
South Norfolk	Labour	13,182	Conservative	12,260	Reform	12,259	923	1.25%

Predicted Closest Three-Way Marginal Seats