Merthyr Tydfil and Aberdare
Wales · County constituency
About the Merthyr Tydfil and Aberdare constituency
Merthyr Tydfil and Aberdare is a county constituency in Wales. The sitting MP is Gerald Jones (Labour), first elected in May 2015. At the 2024 general election, Labour won with 44.8% to 23.7% for Reform UK, a majority of 7,447 votes on a 47.3% turnout. PollCheck's current projection, at the seven-poll average, has Reform UK on 28.2% and Labour on 28.1%, a margin of 0.1 points - a projected change of hands from Labour.
Who lives in Merthyr Tydfil and Aberdare? Constituency demographics
From the 2021 Census and 2016 EU referendum estimates. Constituency-level data on 2024 boundaries.
How did Merthyr Tydfil and Aberdare vote in 2024 and how would it vote now?
2024 vote shares from the HoC Library. Current projection is at the 7-poll average.
2024 general election
Current projection
Map of Merthyr Tydfil and Aberdare
Switch between GE2024 ward winners (modelled estimates, ~4pp average error) and a demographic view from the 2021 Census. Hover any area for detail. How the map is built ›
How Merthyr Tydfil and Aberdare voted at the Senedd election (7 May 2026)
Merthyr Tydfil and Aberdare sits almost entirely within the Senedd constituency of Pontypridd Cynon Merthyr. Senedd elections use a closed-list proportional system; each Senedd seat returns six members.
| Senedd constituency | Share of Merthyr Tydfil and Aberdare | Winner | Runner-up | Seats (6 per constituency) |
|---|---|---|---|---|
| Pontypridd Cynon Merthyr | 99% | Plaid Cymru 39.5% | Reform UK 30.6% | 3 Plaid Cymru, 2 Reform UK, 1 Labour |
Senedd 2026 results from official declarations. Overlap percentages are area-based using the post-2024 Westminster boundary against the new 16-seat Senedd boundary.
Merthyr Tydfil and Aberdare within Merthyr Tydfil and Rhondda Cynon Taf
Merthyr Tydfil and Aberdare crosses council boundaries: Merthyr Tydfil (59%), Rhondda Cynon Taf (41%). None of the constituent councils were due to vote in 2026, so the figures below are the most recent ward results available. About this layer ›
Council overlap
| Council | Share of seat |
|---|---|
| Merthyr Tydfil | 59% |
| Rhondda Cynon Taf | 41% |
Recent council by-elections
Council ward by-elections held inside this seat, most recent first. The result column shows which party won; the share column shows the top three parties’ vote shares on the day.
| Date | Ward | Result | Top 3 vote shares |
|---|---|---|---|
| 25 Jun 2026 | Dowlais & Pant | Lab GAIN from Ind | Lab 40% Other 24% Ref 18% |
| 6 Sep 2024 | Bedlinog and Trelewis | Lab GAIN from Ind | — |
Most recent council ward results
Latest council winner per ward - May 2026 results where the council voted, otherwise the most recent available result. How this table is sourced ›
| Ward | GE2024 winner | Latest council winner | Shift since GE2024 | Turnout |
|---|---|---|---|---|
| Aberaman | Labour 46.4%vs Reform 23.0% | 2022 Labour 78.8%vs Plaid Cymru 15.5% | - | - |
| Aberdare East | Labour 48.1%vs Reform 23.5% | 2022 Labour 76.6%vs Plaid Cymru 15.8% | - | - |
| Aberdare West and Llwydcoed | Labour 47.5%vs Reform 22.2% | 2022 Labour 78.9%vs Plaid Cymru 12.1% | - | - |
| Bedlinog and Trelewis | Labour 40.1%vs Reform 24.8% | 2022 Independent 59.6%vs Labour 37.4% | - | - |
| Cwmbach | Labour 48.4%vs Reform 21.4% | 2022 Labour 56.0%vs Plaid Cymru 17.9% | - | - |
| Cyfarthfa | Labour 42.1%vs Reform 26.6% | 2022 Independent 51.7%vs Labour 36.8% | - | - |
| Dowlais and Pant | Labour 39.3%vs Reform 30.1% | 2022 Independent 65.5%vs Labour 31.3% | - | - |
| Gurnos | Labour 37.3%vs Reform 30.6% | 2022 Independent 64.1%vs Labour 35.9% | - | - |
| Hirwaun, Penderyn and Rhigos | Labour 35.8%vs Plaid Cymru 26.5% | 2022 Plaid Cymru 62.4%vs Labour 32.0% | - | - |
| Merthyr Vale | Labour 47.6%vs Reform 19.1% | 2022 Labour 85.3%vs Independent 14.7% | - | - |
| Park | Labour 44.2%vs Reform 24.6% | 2022 Labour 61.2%vs Independent 38.8% | - | - |
| Pen-y-waun | Labour 47.2%vs Reform 25.8% | 2022 Labour 77.3%vs Plaid Cymru 12.4% | - | - |
| Penydarren | Labour 44.2%vs Reform 26.1% | 2022 Labour 57.3%vs Independent 36.2% | - | - |
| Plymouth | Labour 48.3%vs Reform 21.7% | 2022 Labour 81.2%vs Independent 18.8% | - | - |
| Town | Labour 43.5%vs Reform 25.3% | 2022 Independent 44.0%vs Labour 39.3% | - | - |
| Treharris | Labour 56.1%vs Reform 16.0% | 2022 Labour 67.1%vs Independent 19.1% | - | - |
| Vaynor | Labour 37.8%vs Reform 24.4% | 2022 Independent 80.9%vs Labour 19.1% | - | - |
Projection trajectory
PollCheck's projection for Merthyr Tydfil and Aberdare at each of the last 60 GB polls. Hover the chart for the underlying poll details.
Who has won Merthyr Tydfil and Aberdare at past general elections?
2024 and notional 2019 rows are on current boundaries; 2010-2017 rows are on the boundaries in force at the time. More on boundaries ›
| Year | Result | MP | Lab | Con | LD | Majority | Turnout |
|---|---|---|---|---|---|---|---|
| 2010predecessor | Lab hold | Ann Clwyd Cynon Valley MP | 52.5% | 10.1% | 13.8% | 9,617 | 59.0% |
| 2015predecessor | Lab hold | Ann Clwyd Cynon Valley MP | 47.7% | 12.1% | 2.7% | 9,406 | 59.3%+0.3 |
| 2017predecessor | Lab hold | Ann Clwyd Cynon Valley MP | 61.0% | 19.4% | 1.8% | 13,238 | 62.0%+2.7 |
| 2019notional | Labour winner | Beth Winter Cynon Valley MP, pre-review boundary | 51.7% | 20.6% | 3.3% | 13,410 | 57.6% |
| 2024 | Lab hold | Gerald Jones | 44.8% | 7.6% | 3.6% | 7,447 | 47.3%-10.3 |
Merthyr Tydfil and Aberdare was created or substantially redrawn by the 2023 boundary review. Pre-2024 rows below are for the predecessor seat Cynon Valley (the seat that covered most of this area), so vote shares and majorities aren’t directly comparable to the post-2024 figures.
Constituencies most like Merthyr Tydfil and Aberdare
Five seats with similar demographic profiles to Merthyr Tydfil and Aberdare. Politics shown for context.
- ↓Graduate25.4 / 23.7vs 33.7
- ↑No quals26.0 / 27.0vs 18.0
- ↓Employed52.5 / 50.4vs 57.3
- ↓Graduate25.4 / 27.3vs 33.7
- ↓Employed52.5 / 52.3vs 57.3
- ↓Private rent16.1 / 15.4vs 20.2
- ↓Graduate25.4 / 27.2vs 33.7
- ↓Private rent16.1 / 17.2vs 20.2
- ↑No quals26.0 / 21.7vs 18.0
- ↓Graduate25.4 / 25.7vs 33.7
- ↓Private rent16.1 / 16.0vs 20.2
- ↓Employed52.5 / 53.6vs 57.3
- ↓Graduate25.4 / 26.9vs 33.7
- ↓Private rent16.1 / 13.1vs 20.2
- ↑No quals26.0 / 21.4vs 18.0
What would change this seat?
Move the sliders to set national vote shares. The per-seat projection updates live. Reset returns to the current 7-poll average.
Related
Sources
Every figure on this page is computed from the sources below. Read the full methodology ›
Show full source list
- 2024 general election results · UK Parliament Election Results portal and House of Commons Library briefing CBP-10009.
- Notional 2019 results on 2024 boundaries · UK Parliament Election Results portal. Recalculated by Parliament; carries assumptions about how 2019 voters would have distributed across the redrawn boundaries.
- Historic general election results (2010-2017) · House of Commons Library historic results files (on the boundaries in force at the time).
- Ward-level GE2024 estimates · Britain Elects / New Statesman - article by Ben Walker, underlying spreadsheet. Modelled from constituency totals; average ~4pp per-ward MoE.
- May 2026 council ward results · Democracy Club via PollCheck's locals 2026 dataset.
- Earlier council ward results (2014-2024) · DCLEAPIL v1.0 (Jason Leman, drawing on Andrew Teale's LEAP dataset and Democracy Club).
- Demographics · ONS Census 2021 (England and Wales), aggregated to constituency level using the ONS LSOA21 -> PCON24 best-fit lookup.
- EU referendum 2016 estimates · Constituency-level Leave vote estimates (Hanretty 2017 method).
- MP details and Cabinet roles · UK Parliament Members API. MP photos are fetched live from the same source.
- Boundary geometry and lookups · ONS Open Geography Portal (PCON24 boundaries, LSOA21 boundaries, LSOA21-WD24-LAD24 best-fit lookup).
- Current projection and trajectory · PollCheck's demographic swingometer applied to the rolling 7-poll average from aggregated GB polls. Not a true MRP - vote-share movements are applied through per-constituency sensitivity multipliers derived from demographic regressions.
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