Local council · Merton
St Helier
3 seats contested on Thursday 7 May 2026. 15 candidates from 5 parties.
Neighbours shaded by Reform UK share vs this ward, red = higher, blue = lower.
Predicted vote share
What the model expects
Predictions are point estimates: the model's best guess, not a guarantee. The "How this prediction was made" section below lists every step that shaped this forecast.
How accurate was the model here?
Our 7 May 2026 forecast for St Helier
| Party | Predicted | Actual | Gap |
|---|---|---|---|
| Reform UK | 15.8% | 16.8% | -1.0pp |
| Labour | 24.7% | 39.0% | -14.3pp |
| Conservative | 15.0% | 8.4% | +6.6pp |
Positive gap = we predicted that party would win more share than they did. See the full Merton accuracy summary or the national audit.
Recent contests
What happened last time
| Date | Type | Winner | Top share | Source |
|---|---|---|---|---|
| 2024-07-04 | By-election | Labour Party | 47.9% | declaration |
| 2022-05-05 | Cycle | Labour Party | 21.3% | declaration |
| 2021-05-06 | By-election | Labour Party | 54.4% | declaration |
| 2018-05-03 | Cycle | Labour Party | 24.4% | declaration |
| 2017-07-20 | By-election | Labour Party | 74.1% | declaration |
Candidates 2026
Parties on the ballot
- Conservative and Unionist Party
- Green Party
- Labour Party
- Lib Dem
- Reform UK
How this area looks demographically
Figures are for Merton as a whole. The same local-authority figures are used for every ward in the council, finer ward-level demographics will land in a future release.
- White British (projected May 2026): 37.2% (Census 2021: 41.2%)
- Asian heritage (projected May 2026): 18.3% (Census 2021: 18.6%)
- Average area deprivation decile: 6.9 (1 = most deprived, 10 = least)
How this prediction was made
- Baseline . Most recent borough result (2024-07-04)
- BES MRP Prior . Baseline blended with BES Wave 1-30 london prior (weight 15%, n=3660 regional respondents)
- National Swing (STM) . Strong Transition Model: multiplicative bounded swing, dampened by 0.65 for local
- Demographics . 1 demographic factor(s) applied
- Incumbency . No current holder data available
- New Party Entry . Reform UK estimated at 12.8% from GE/LCC proxy + swing
- Normalise . All shares scaled to sum to 100%
- Restrict to ballot . Removed 3 party/parties not standing in 2026 (SNP 0.5pp, Plaid Cymru 0.2pp, Other 0.0pp). Their share redistributed pro-rata.
- 2025 county-cycle anchor . No 2025 reference available for this council's parent area. Stage 1 uses national polling only.
- National-share calibration . Aggregate-predicted vs national-polled mismatch corrected at strength 0.65. Multipliers — Labour ×0.82, Conservative ×1.00, Reform UK ×1.15, Liberal Democrats ×0.96, Green Party ×1.12, SNP ×1.00, Plaid Cymru ×1.00.