How we count

What you see

Every price is in pence per litre, so 197.9p means £1.979. For each region, town and brand you get the median, the tenth and ninetieth percentiles and the cheapest price. Half the forecourts in a group charge the median or less, and one odd price barely moves it. The trend chart uses a snapshot saved once a day. Nothing is rebuilt after the fact.

Where it comes from

Retailers' open price feeds, published under the CMA's voluntary scheme and read every hour. Each feed carries its own last-updated stamp. Feeds not updated for more than three days are left out, and so are prices above 160% or below 80% of the national median. Each forecourt goes to a region by its postcode area — the English regions used by the Office for National Statistics, plus Scotland, Wales and Northern Ireland. Some postcode areas straddle a boundary, so regional counts are close rather than exact.

What is missing

The government withdrew the guidance for the voluntary scheme in May 2026, when the statutory Fuel Finder scheme took over. Several retailers have stopped updating their feeds since, so some big chains are missing and coverage is partial. The feeds say nothing about stock, so neither do we. We never estimate a missing price.