Supermarket forecourts are where most cost-conscious UK drivers fill up — but which chain is actually cheapest right now? Unlike most answers online, this one comes from live data: Fuel Near You tracks every forecourt reporting under the government's Fuel Finder scheme.
Quick answer: On July 2026 national averages, Asda has the cheapest supermarket petrol (~147.1p) and Morrisons the cheapest diesel (~159.8p) — but all four big supermarkets are within about 1p of each other, and they all undercut BP and Shell by 5–6p a litre. Costco (members only) beats the lot at ~141p. Locally the picture varies street by street, so check live prices near you before you drive.
The supermarket fuel league table (July 2026 averages)
Live national averages across every UK forecourt we track:
| Retailer | Petrol (E10) | Diesel (B7) | Stations |
|---|---|---|---|
| Asda | 147.1p | 160.5p | 320 |
| Sainsbury's | 147.3p | 160.2p | 315 |
| Morrisons | 147.4p | 159.8p | 340 |
| Tesco | 147.9p | 161.1p | 1,031 |
| — UK average — | ~150.7p | ~164.8p | 8,500+ |
| Esso | 150.9p | 165.3p | 1,342 |
| BP | 153.2p | 167.5p | 986 |
| Shell | 153.4p | 167.7p | 772 |
(Averages of live forecourt prices, early July 2026, rounded to 0.1p. For members: Costco averages ~141p petrol / ~153p diesel — see our Costco fuel guide.)
Three things jump out:
- The big four supermarkets are separated by less than 1p. Asda edges petrol, Morrisons edges diesel, but nationally it's effectively a dead heat.
- The supermarket discount is real: ~3.5p below the UK average, ~6p below BP and Shell. On a 50-litre tank, filling at a supermarket rather than a Shell saves about £3 every time.
- Tesco has by far the biggest network (1,000+ forecourts), so it's most likely to be the convenient cheap option even when it isn't the absolute cheapest.
Why no single supermarket is always cheapest near you
National averages hide the local battle. Supermarkets set fuel prices store by store, mainly to match or beat whoever is nearby:
- The same chain can be 5–10p cheaper in one town than another a short drive away.
- The chain that's cheapest near you might be dearest near a friend across the county.
- Prices shift through the week and respond fast to local competition.
So use the table above for the big picture — but for this morning's fill-up, local live data beats reputation every time. Your town's page on our prices by city index shows today's actual cheapest forecourt.
Supermarket vs branded fuel: is the quality the same?
For everyday driving, yes. All UK fuel — supermarket or branded — meets the same BS EN 228 (petrol) and BS EN 590 (diesel) standards, and all of it includes detergent additive packages. Branded "premium" fuels (Shell V-Power, BP Ultimate) carry extra additives that can benefit high-performance or older engines, but for a normal car the 5–6p/litre supermarket saving comfortably outweighs the difference. More detail: supermarket vs branded fuel.
How to actually pay the least
- Check live prices before you drive — the map sorts every forecourt near you, cheapest first, updated every 15 minutes.
- Don't cross town for 0.3p. The supermarket gap is tiny; burning half a litre to save 15p is a loss. The gap that matters is supermarket vs motorway services (15–30p) — use the fuel cost calculator to sanity-check any detour.
- Stack the loyalty points at whichever supermarket is cheapest — see our loyalty cards comparison.
- Near a Costco and drive a lot? The membership pays for itself — full breakdown.
- Grab voucher promotions — "10p off per litre with £40 grocery spend" events beat every points scheme going.
Check your local picture
- Live fuel map — every station near you
- UK fuel prices today — live national averages
- Asda · Tesco · Sainsbury's · Morrisons — live prices by brand
Figures are national averages of live forecourt prices tracked by Fuel Near You under the UK Government Fuel Finder scheme, July 2026. Your local prices will differ — always check the live map.
Frequently Asked Questions
Which supermarket has the cheapest fuel in 2026?
On July 2026 national averages tracked by Fuel Near You: Asda has the cheapest petrol (about 147.1p/litre) and Morrisons the cheapest diesel (about 159.8p). But all four big supermarkets sit within 1p of each other and price locally, so the cheapest one near you changes town by town — always check live prices.
How much cheaper are supermarkets than BP or Shell?
Around 5–6p per litre on average in July 2026: supermarket petrol averages ~147–148p versus ~153p at BP and Shell. On a 50-litre tank that's about £3 per fill.
Is supermarket fuel as good as branded fuel?
Yes, for everyday driving. All UK fuel meets the same BS EN standards. Premium branded fuels add extra cleaning additives, but standard supermarket fuel is fine for most cars.
Is Costco fuel really cheaper than supermarkets?
Usually, yes — Costco averages around 141p for petrol in July 2026, roughly 6p below even Asda, but you need a paid membership and there are only around 21 fuel sites in the UK.
Why do supermarket fuel prices vary so much between towns?
Supermarkets price locally to match nearby competitors, so the same chain can be several pence cheaper in one town than another a few miles away. That's why live comparison beats brand loyalty.
Does premium supermarket fuel make a difference?
For most ordinary cars, standard fuel is perfectly adequate. Premium fuels can help high-performance or older engines, but for everyday driving the price saving usually outweighs the benefit.