Weekly bulletin, 14 to 20 September 2026. Published Monday 21 September 2026.
Petrol prices in Wales: up 2.6p this week to 172.1p
Between Monday 14 September 2026 and Sunday 20 September 2026, the average price of unleaded across 400 filling stations in Wales rose 2.6p to 172.1p a litre, while diesel rose 4.3p to 196.1p.
Cheapest and most expensive
On Sunday 20 September 2026, prices updated within 30 days, judged against their neighbours.
The last 30 days
Daily averages, in pence per litre. Right-click the image to save it; it is free to publish with a link.
Towns in Wales where unleaded moved most
Towns with at least three filling stations, first to last day of the week.
Biggest falls
| Town | Stations | Now | Week |
|---|
Biggest rises
| Town | Stations | Now | Week |
|---|---|---|---|
| Colwyn Bay | 3 | 174.6p | ▲ 4.7p |
| Caernarfon | 6 | 170.9p | ▲ 4.1p |
| Cardigan | 4 | 165.7p | ▲ 4.0p |
Stations that joined or went silent this week
Stations that reported their first price during the week, and stations whose last price came before or during it and that have been silent for 7 days or more since.
Started reporting 3
- H G Thomas Motors Limited, Corwen, LL21 0HA, 15 Sep
- Minafon Stores, Abergele, LL22 8AW, 14 Sep
- Rhymney Service Station, Tredegar, NP22 5NU, 14 Sep
Stopped reporting 2
- Robert Davies Motors, Aberteifi, SA43 1RQ, 15 Sep
- Robert Davies Motors, Cardigan, SA43 2NR, 15 Sep
A station that stops reporting has not necessarily closed. The full lists: new stations and stations no longer reporting.
Ready to copy
The weekly change compares the same 386 filling stations with an unleaded price on both days, so a station dropping out of the figures does not move it.
434 of the 483 stations seen during the week changed at least one price.
The cheapest unleaded in Wales on Sunday 20 September 2026 was 161.9p at Milford Haven Superstore - Petrol Filling Station, Milford Haven (SA73 3AU); the most expensive was 189.9p at Asda Kinmel Park West Express Petrol, Bodelwyddan (LL18 5XW), a gap of 28.0p, or £14.00 on a 50-litre tank.
The cheapest diesel was 107.9p at Parc Service Station, Corwen (LL21 9HH).
Across the UK, unleaded was up 2.3p over the same week, at 172.3p, which puts Wales 0.2p below the national average.
Among the towns of Wales, unleaded rose most in Colwyn Bay (up 4.7p to 174.6p), Caernarfon (up 4.1p to 170.9p), Cardigan (up 4.0p to 165.7p).
"Drivers in Wales paid 2.6p more for a litre of unleaded this week. On a 50-litre tank, that is £1.30 more than a week earlier. The gap between the cheapest and the dearest forecourt in Wales is 28.0p, so where you fill up still matters more than when." said Jacky A., editor of fuelpricetoday.co.uk.
Show the plain text
Petrol prices in Wales: up 2.6p this week to 172.1p Between Monday 14 September 2026 and Sunday 20 September 2026, the average price of unleaded across 400 filling stations in Wales rose 2.6p to 172.1p a litre, while diesel rose 4.3p to 196.1p. The weekly change compares the same 386 filling stations with an unleaded price on both days, so a station dropping out of the figures does not move it. 434 of the 483 stations seen during the week changed at least one price. The cheapest unleaded in Wales on Sunday 20 September 2026 was 161.9p at Milford Haven Superstore - Petrol Filling Station, Milford Haven (SA73 3AU); the most expensive was 189.9p at Asda Kinmel Park West Express Petrol, Bodelwyddan (LL18 5XW), a gap of 28.0p, or £14.00 on a 50-litre tank. The cheapest diesel was 107.9p at Parc Service Station, Corwen (LL21 9HH). Across the UK, unleaded was up 2.3p over the same week, at 172.3p, which puts Wales 0.2p below the national average. Among the towns of Wales, unleaded rose most in Colwyn Bay (up 4.7p to 174.6p), Caernarfon (up 4.1p to 170.9p), Cardigan (up 4.0p to 165.7p). "Drivers in Wales paid 2.6p more for a litre of unleaded this week. On a 50-litre tank, that is £1.30 more than a week earlier. The gap between the cheapest and the dearest forecourt in Wales is 28.0p, so where you fill up still matters more than when." said Jacky A., editor of fuelpricetoday.co.uk. Source: fuelpricetoday.co.uk, weekly bulletin for Wales, 14 to 20 September 2026. https://fuelpricetoday.co.uk/press/2026-W38/wales Prices are pence per litre, computed from the government's Fuel Finder open data. Free to use with a link to the source.
Download the data
- Every station (CSV)
Name, brand, postcode, coordinates, unleaded and diesel on 14 Sep and 20 Sep.
- This bulletin (JSON)
All the figures on this page, with the 30-day series.
- The chart (PNG)
1200 by 630 pixels, white background.
Terms of use
Free to use, quote and publish, including the chart and the data, with a link to https://fuelpricetoday.co.uk/press/2026-W38/wales or a credit to fuelpricetoday.co.uk. Prices are computed from the Fuel Finder open data published by the Department for Energy Security and Net Zero under the Open Government Licence v3.0. Questions, a figure for another area, or a quote: contact@fuelpricetoday.co.uk.
How the figures are computed
Each average is the mean of the prices changed in the last 7 days at the filling stations of Wales, motorway services left out and prices more than 25p from the day's median discarded. The cheapest and most expensive stations are judged against the stations within 10 km, so that a typing error cannot top the list. The week runs from Monday to Sunday. Details on how this site works.