Frequently Asked
Questions

B7 diesel is the standard diesel fuel in the UK, containing up to 7% biodiesel (fatty acid methyl ester - FAME). The "B" stands for biodiesel and the "7" indicates the maximum percentage.

All diesel cars sold in the UK are compatible with B7. The biodiesel content helps reduce overall carbon emissions compared to pure fossil diesel.

Super Diesel (also known as Premium Diesel or Supreme Diesel) is a higher-grade diesel fuel with additional cleaning agents and higher cetane numbers.

Potential benefits include:

• Better engine cleaning properties
• Improved fuel efficiency (though usually marginal)
• Smoother engine running
• Reduced emissions

However, for most modern diesel vehicles, standard B7 diesel is perfectly adequate. The extra cost of premium diesel rarely pays for itself in fuel savings.

Most petrol cars manufactured from 2011 onwards are fully compatible with E10 petrol. However, some older vehicles and classic cars may not be compatible.

To check if your vehicle is compatible:

• Check the label inside your fuel filler cap
• Look in your vehicle handbook
• Use the government's E10 compatibility checker at gov.uk
• Contact your vehicle manufacturer

If your car isn't compatible with E10, you should use E5 (Super Unleaded) instead. Using E10 in an incompatible vehicle occasionally won't cause immediate damage, but long-term use could harm fuel system components.

Fuel prices can vary significantly between stations for several reasons:

• Location: Motorway service stations have captive audiences and charge premium prices. Rural stations may have higher transport costs.
• Competition: Areas with multiple nearby stations tend to have lower prices due to competition.
• Business model: Supermarkets often use fuel as a loss leader to attract shoppers, while independent stations need higher margins to survive.
• Wholesale costs: Different retailers have different supply agreements and buying power.
• Rent and rates: Operating costs vary by location.

Supermarkets like Asda, Sainsbury's, Tesco, and Morrisons typically offer the cheapest fuel because:

• Loss leader strategy: They're willing to accept lower fuel margins to attract customers who will then shop in-store.
• Buying power: Large supermarket chains can negotiate better wholesale prices due to volume.
• Efficiency: High-volume sales mean lower per-litre operating costs.
• Price matching: Supermarkets actively compete with each other on fuel prices.

The fuel itself is the same quality as branded stations - all UK fuel must meet the same BS EN 228 (petrol) or BS EN 590 (diesel) standards.

Motorway service stations are consistently the most expensive places to buy fuel in the UK. Prices can be 20-30p per litre higher than local stations.

The main reasons are:

• Captive customers: Drivers often have no alternative when they need fuel on the motorway.
• High operating costs: 24/7 staffing, large premises, and expensive land leases.
• Franchise fees: Service station operators pay high rents to Highways England.
• Lower competition: There's no nearby competition to drive prices down.

Tip: Plan ahead and fill up before joining the motorway, or leave at a junction to find cheaper fuel nearby.

Fuel prices can change daily, though most stations update prices a few times per week. The frequency depends on:

• Wholesale price movements: When oil prices change significantly, retailers adjust accordingly.
• Competitor pricing: Stations monitor local competitors and may match price changes.
• Delivery costs: New deliveries may come at different wholesale prices.

Our data is updated every 30 minutes from official retailer feeds, so you always see the most current prices available.

Fuel Finder is the UK Government's official fuel price transparency scheme, launched in 2024. Under this scheme, major fuel retailers are legally required to publish their pump prices in real-time.

The Fuel Finder initiative was introduced to help drivers compare fuel prices and find the cheapest petrol and diesel near them. All data is published through official government APIs.

Fuelwise uses the official Fuel Finder data to show you live prices from thousands of UK petrol stations — making it easy to find cheap fuel without visiting multiple websites.

Our fuel price data comes directly from the UK Government's Fuel Finder scheme. Since 2024, major UK fuel retailers are required by law to publish their prices in a standardised format.

We currently aggregate Fuel Finder data from 14 major retailers including Asda, BP, Esso, Shell, Tesco, Sainsbury's, Morrisons, and others.

Prices are updated every 30 minutes to ensure accuracy. However, there may occasionally be brief delays between a station changing its prices and our data reflecting that change.

Yes! Fuelwise is completely free to use. We don't charge for searches, we don't require registration, and we don't sell your data.

We built this tool to help UK drivers save money on fuel. Our goal is to make fuel price comparison quick, easy, and accessible to everyone.

We pull data directly from official retailer feeds, which are required to be accurate under government regulations. However:

• There may be a brief delay between a price change at the pump and it appearing in the feed.
• Some stations may not update their feeds immediately after changing prices.
• Technical issues can occasionally cause data delays.

For the most critical journeys, we recommend double-checking the price when you arrive at the station. Prices shown are a reliable guide but not a guarantee.

We can only show prices from retailers who publish official price data. Currently, this includes major chains and supermarkets.

Independent stations and some smaller chains don't yet participate in the government's fuel price transparency scheme, so their prices aren't available in our database.

As more retailers join the scheme, we'll automatically include their stations in our results.

It depends on the price difference and distance. Here's a rough guide:

For a 50-litre tank, every 1p per litre difference equals 50p total savings. If petrol costs 140p/litre and your car does 40mpg:

• 5p cheaper, 2 miles away: Worth it - saves £2.50, costs ~25p in fuel to get there
• 3p cheaper, 5 miles away: Borderline - saves £1.50, costs ~63p in fuel
• 2p cheaper, 10 miles away: Not worth it - saves £1.00, costs ~£1.25 in fuel

Use our distance information to make an informed decision, but don't drive miles out of your way for tiny savings.

There's no consistent "cheapest day" to buy fuel in the UK. Unlike some countries, UK retailers don't follow predictable weekly price cycles.

However, there are some patterns:

• Avoid bank holidays: Prices sometimes rise before long weekends due to increased demand.
• Watch for supermarket price wars: These often happen mid-week and can save you 2-3p per litre.
• Check prices before filling: Using our site takes seconds and could save you pounds.

Loyalty cards typically offer small savings (around 1% cashback or equivalent in points). They can be worth using if:

• You're already buying fuel at that retailer
• The station has competitive base prices
• You'll actually use the rewards

However, don't let loyalty cards drive your fuel buying decisions. A 1% loyalty bonus is meaningless if you're paying 5p more per litre than a competitor without a loyalty scheme.

Priority order: Find the cheapest fuel first, then use a loyalty card if available.