UK Fuel Cost Calculator
Petrol vs Diesel Comparison
Compare running costs between petrol and diesel vehicles for your annual mileage.
UK Fuel Prices 2025
| Fuel Type | Average Price | Supermarket | Motorway |
|---|---|---|---|
| Unleaded Petrol | 140-150p/L | 138-145p/L | 160-175p/L |
| Diesel | 145-155p/L | 143-150p/L | 165-180p/L |
| Premium Petrol | 160-170p/L | 155-165p/L | 180-195p/L |
| LPG | 70-80p/L | 68-75p/L | 85-95p/L |
Fuel Price Tip
Supermarket fuel stations (Tesco, Asda, Sainsbury's, Morrisons) are typically 3-8p/litre cheaper than branded stations. Motorway services charge 15-25p/litre premium - always fuel up before joining motorway!
Average UK Vehicle MPG Guide
| Vehicle Type | Petrol MPG | Diesel MPG | Cost/Mile |
|---|---|---|---|
| Small Car (Fiesta, Polo) | 50-60 MPG | 60-70 MPG | 11-14p |
| Medium Car (Golf, Focus) | 42-52 MPG | 55-65 MPG | 13-17p |
| Large Car (Mondeo, Passat) | 35-45 MPG | 50-60 MPG | 15-20p |
| Small SUV (Qashqai, Tucson) | 38-48 MPG | 50-58 MPG | 14-18p |
| Large SUV (Range Rover, X5) | 25-35 MPG | 35-45 MPG | 20-28p |
| Hybrid (Prius, Yaris Hybrid) | 55-70 MPG | - | 9-13p |
7 UK Fuel Saving Strategies
Use Supermarket Fuel Stations
Save 3-8p/litre at Tesco, Asda, Sainsbury's, Morrisons. Use PetrolPrices.com app to find cheapest local station. Annual saving: £100-250/year.
Drive Smoothly
Gentle acceleration, anticipate traffic, ease off early for junctions. Aggressive driving wastes 20-30% fuel. Annual saving: £300-600/year.
Optimal Motorway Speed
60-65mph is fuel-efficient sweet spot. 70mph uses 9% more than 60mph, 80mph uses 25% more. Use cruise control. Annual saving: £80-150/year.
Maintain Tire Pressure
Under-inflated tires (20% low) waste 3-5% fuel. Check monthly when cold. Add 2 PSI for motorway driving. Annual saving: £60-120/year.
Remove Unnecessary Weight
Every 50kg costs 1-2% fuel. Clear out boot junk, remove roof rack/box when not in use. Roof box at motorway speeds costs 10-25% more fuel.
Plan Routes Efficiently
Use Google Maps/Waze with live traffic. Combine errands into single trip. Avoid rush hour. Cold engine uses 50% more fuel first 5 miles.
Regular Vehicle Maintenance
Dirty air filter costs 7% MPG. Worn spark plugs cost 5%. Annual service (£200) pays for itself in fuel savings. Keep engine oil topped up.
Combined Fuel Savings Potential
Implementing all 7 strategies can save £500-1,500/year for typical UK driver doing 12,000-15,000 miles/year. Even 3-4 strategies saves £300-600/year.
Common UK Journey Fuel Costs
| Journey | Miles | Petrol (45MPG) | Diesel (55MPG) |
|---|---|---|---|
| London to Birmingham | 120 | £17.48 | £14.87 |
| London to Manchester | 200 | £29.14 | £24.79 |
| London to Edinburgh | 403 | £58.71 | £49.95 |
| Manchester to Leeds | 44 | £6.41 | £5.46 |
| Birmingham to Bristol | 85 | £12.38 | £10.54 |
| Daily Commute (30mi round) | 30 | £4.37 | £3.72 |
* Calculations based on 145p/L petrol, 150p/L diesel. January 2025 average prices.
Frequently Asked Questions
UK fuel prices January 2025:
- Unleaded petrol: 140-150p/litre (supermarkets 138-145p)
- Diesel: 145-155p/litre (supermarkets 143-150p)
- Premium unleaded: 160-170p/litre
- LPG: 70-80p/litre
Motorway services typically charge 15-25p/litre more. Fuel duty is 52.95p/litre plus 20% VAT on the total.
Calculate journey fuel cost in 3 steps:
- Litres needed: (Distance / MPG) x 4.546
- Cost: Litres x Price per litre
Example: 200 miles at 45 MPG, fuel at 145p/L
Litres = (200 / 45) x 4.546 = 20.2 litres
Cost = 20.2 x £1.45 = £29.29
Diesel typically costs less per mile due to 20-30% better fuel economy, despite higher pump prices:
- Petrol: 145p/L at 45 MPG = 14.6p per mile
- Diesel: 150p/L at 55 MPG = 12.4p per mile (15% cheaper per mile)
For 12,000 miles/year, diesel saves approximately £260/year in fuel costs. However, diesel cars typically cost £1,000-2,000 more to purchase, so break-even is around 12,000+ annual miles.
Petrol cars:
- Excellent: 55+ MPG (hybrids, small economical cars)
- Good: 45-55 MPG (small to medium cars)
- Average: 35-45 MPG (medium to large cars)
- Below average: Under 35 MPG (SUVs, performance cars)
Diesel cars: Typically 10-20% better than equivalent petrol. A "good" diesel achieves 55-70 MPG.
Real-world tip: City driving typically achieves 20-30% lower MPG than manufacturer figures. Motorway driving is closer to rated MPG.
Seven proven strategies to cut UK fuel costs:
- Shop around: Use PetrolPrices app - save 5-10p/L at supermarkets
- Drive smoothly: Gentle acceleration, anticipate traffic - improves MPG 20-30%
- Optimal speed: 60-65mph uses 15-25% less fuel than 80mph
- Tire pressure: Check monthly - under-inflation costs 3-5% fuel
- Remove weight: Clear boot, remove roof rack when not in use
- Use cruise control: Maintains steady speed - 5-10% motorway saving
- Regular servicing: Dirty filters, worn plugs reduce economy 5-10%
Combined potential savings: £500-1,500/year for 12,000-15,000 mile/year driver.
EV running costs vs petrol (2025):
- Home charging (off-peak): 7-10p/kWh = 2-3p per mile
- Petrol at 145p/L, 45 MPG = 14.6p per mile
- Savings: 80% cheaper per mile on home charging
For 12,000 miles/year: EV costs ~£400-600, petrol costs ~£1,750. However, EVs cost £5,000-15,000 more to buy, so break-even takes 4-10 years.
Best for: High-mileage drivers, those with home charging, company car users (2% BIK tax).
Motorway services typically charge 15-25p/litre more than supermarkets or local stations due to:
- Captive market - you can't easily leave motorway
- Higher operating costs for 24/7 operation
- Prime location rental costs
Cost impact: Filling 50L tank at motorway services (165p/L) vs supermarket (145p/L) = £10 extra per fill. For 20 long trips/year, that's £200 wasted.
Solution: Always fuel up before joining motorway, or just after exiting at local station.
Formula: Cost per mile = (Fuel price in pence / MPG) x 4.546 / 100
Example at 145p/L and 45 MPG:
Cost per mile = (145 / 45) x 4.546 / 100 = 14.65p per mile
Quick reference (at 145p/L petrol):
- 35 MPG = 18.8p/mile
- 45 MPG = 14.6p/mile
- 55 MPG = 12.0p/mile