Ynys Mon
Wales · County constituency · Isle of Anglesey borough
About the Ynys Mon constituency
Ynys Mon is a county constituency in Wales. The sitting MP is Llinos Medi (Plaid Cymru), first elected in July 2024. At the 2024 general election, Plaid Cymru won with 32.5% to 30.5% for the Conservatives, a majority of 637 votes on a 61.4% turnout. PollCheck's current projection, at the seven-poll average, has Plaid Cymru on 42.1% and the Conservatives on 24.1%, a margin of 18.0 points.
Who lives in Ynys Mon? Constituency demographics
From the 2021 Census and 2016 EU referendum estimates. Constituency-level data on 2024 boundaries.
How did Ynys Mon 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 Ynys Mon
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 Ynys Mon voted at the Senedd election (7 May 2026)
Ynys Mon sits entirely within the Senedd constituency of Bangor Conwy Môn. Senedd elections use a closed-list proportional system; each Senedd seat returns six members.
| Senedd constituency | Share of Ynys Mon | Winner | Runner-up | Seats (6 per constituency) |
|---|---|---|---|---|
| Bangor Conwy Môn | 100% | Plaid Cymru 44.9% | Reform UK 28.1% | 3 Plaid Cymru, 2 Reform UK, 1 Conservative |
Senedd 2026 results from official declarations. Overlap percentages are area-based using the post-2024 Westminster boundary against the new 16-seat Senedd boundary.
Ynys Mon within Isle of Anglesey
Ynys Mon sits entirely within Isle of Anglesey Council. Isle of Anglesey was not 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 |
|---|---|
| Isle of Anglesey | 100% |
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 |
|---|---|---|---|
| 30 Jul 2026 | Bro'r Llynnoedd | PC HOLD | PC 48% Ref 39% Con 8% |
| 6 Feb 2026 | Ynys Gybi | Ref GAIN from PC | Ref 44% PC 25% Lab 12% |
| 28 Oct 2024 | Talybolion | Ind GAIN from PC | — |
| 21 Apr 2023 | Aethwy | PC HOLD | — |
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 |
|---|---|---|---|---|
| Aethwy | Plaid Cymru 36.6%vs Conservative 27.9% | 2022 Plaid Cymru 67.8%vs Conservative 15.8% | - | - |
| Bodowyr | Plaid Cymru 31.5%vs Labour 28.5% | 2022 Independent 43.3%vs Plaid Cymru 23.8% | - | - |
| Bro Aberffraw | Plaid Cymru 36.2%vs Conservative 26.6% | 2022 Plaid Cymru 46.6%vs Independent 42.6% | - | - |
| Bro'r Llynnoedd | Conservative 32.3%vs Plaid Cymru 30.6% | 2022 Independent 48.4%vs Conservative 26.9% | - | - |
| Cefni | Plaid Cymru 40.2%vs Conservative 25.7% | 2022 Plaid Cymru 57.4%vs Independent 29.9% | - | - |
| Crigyll | Plaid Cymru 36.7%vs Conservative 25.9% | 2022 Independent 66.8%vs Plaid Cymru 25.9% | - | - |
| Lligwy | Conservative 45.4%vs Plaid Cymru 27.1% | 2022 Plaid Cymru 38.0%vs Conservative 36.4% | - | - |
| Parc a'r Mynydd | Labour 31.0%vs Conservative 27.8% | 2022 Independent 50.1%vs Labour 30.7% | - | - |
| Seiriol | Plaid Cymru 38.5%vs Conservative 29.7% | 2022 Plaid Cymru 72.0%vs Conservative 19.9% | - | - |
| Talybolion | Plaid Cymru 35.0%vs Conservative 31.4% | 2022 Plaid Cymru 49.0%vs Independent 27.5% | - | - |
| Tref Cybi | Labour 28.6%vs Plaid Cymru 25.1% | 2022 Labour 38.2%vs Plaid Cymru 27.9% | - | - |
| Twrcelyn | Conservative 31.8%vs Plaid Cymru 26.5% | 2022 Independent 51.9%vs Lib Dem 25.2% | - | - |
| Ynys Gybi | Conservative 35.0%vs Plaid Cymru 29.0% | 2022 Conservative 35.2%vs Independent 27.2% | - | - |
Projection trajectory
PollCheck's projection for Ynys Mon at each of the last 60 GB polls. Hover the chart for the underlying poll details.
Who has won Ynys Mon 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 |
|---|---|---|---|---|---|---|---|
| 2010 | Lab hold | Albert Owen | 33.4% | 22.5% | 7.5% | 2,461 | 68.8% |
| 2015 | Lab hold | Albert Owen | 31.1% | 21.2% | 2.2% | 229 | 69.9%+1.1 |
| 2017 | Lab hold | Albert Owen | 41.9% | 27.8% | 1.3% | 5,259 | 70.6%+0.7 |
| 2019notional | Conservative winner | Virginia Crosbie 2019 MP, pre-review boundary | 30.1% | 35.5% | 0.0% | 1,968 | 69.7%-0.9 |
| 2024 | PC gain from Con | Llinos Medi | 23.4% | 30.5% | 1.3% | 637 | 61.4%-8.3 |
Earlier years are on pre-2024 boundaries; comparable results on the new boundary will be added when sourced.
Constituencies most like Ynys Mon
Five seats with similar demographic profiles to Ynys Mon. Politics shown for context.
- ↑Age 65+31.5 / 32.1vs 22.7
- ↓Under 3523.3 / 22.6vs 30.2
- ↑Owner-occupied68.2 / 69.0vs 61.9
- ↑Age 65+31.5 / 30.5vs 22.7
- ↑Owner-occupied68.2 / 68.2vs 61.9
- ↓Under 3523.3 / 23.9vs 30.2
- ↑Age 65+31.5 / 30.6vs 22.7
- ↓Under 3523.3 / 23.6vs 30.2
- ↑Owner-occupied68.2 / 71.7vs 61.9
- ↑Age 65+31.5 / 30.4vs 22.7
- ↓Employed51.1 / 51.3vs 57.3
- ↓Under 3523.3 / 24.4vs 30.2
- ↑Age 65+31.5 / 31.4vs 22.7
- ↓Under 3523.3 / 25.7vs 30.2
- ↑Owner-occupied68.2 / 66.1vs 61.9
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.
If you spot a data issue, please let us know.