Petrol and Diesel Prices in Carmarthen
Compare petrol and diesel prices at 7 petrol stations in Carmarthen. Prices last updated 04:12 26/09/2026.
Petrol (E10)
169.9p
at Derwydd Services
Diesel (B7)
195.9p
at ASDA WHITE MILL EXPRESS PETROL
Super Unleaded (E5)
178.5p
at GWALIA GARAGE
Premium Diesel
201.5p
at GWALIA GARAGE
Unleaded (E10)
172.0p avg
1.9p below UK average (173.9p)
Diesel
198.0p avg
0.9p below UK average (198.9p)
Price History in Carmarthen
See how fuel prices have changed over time with interactive charts and analysis.
Click any column header to sort. Prices shown in pence per litre.
Stations within a few miles of Carmarthen — worth the short drive for cheaper fuel.
Carmarthen currently has 7 petrol stations tracked by FuelCosts.co.uk. The average unleaded petrol price in Carmarthen today is 172.0p per litre, which is 1.9p below the UK national average of 173.9p.
The cheapest unleaded petrol in Carmarthen right now is 169.9p at Derwydd Services. The cheapest diesel is 195.9p at ASDA WHITE MILL EXPRESS PETROL.
Fuel prices in Carmarthen are sourced from the UK Government's CMA Fuel Finder scheme and updated every 4 minutes. We recommend comparing prices before filling up, as prices can vary significantly between stations even within the same town.