How Much Does It Cost to Drive from London to Cornwall? 🚗
Planning a trip down to Cornwall? The drive from London to Cornwall is one of the UK's most popular holiday routes — but with petrol at 156p/litre, it's worth knowing exactly what it'll cost before you set off. Here's a full breakdown based on real route data and current fuel prices.
Fuel cost by car type — London to Cornwall
| Car type | Real-world MPG | One way | Return |
|---|---|---|---|
| Small petrol (e.g. Polo, Fiesta) | ~42 MPG | ~£27.50 | ~£55 |
| Family petrol (e.g. Golf, Focus) | ~38 MPG | ~£30.50 | ~£61 |
| Petrol SUV (e.g. Qashqai, Tucson) | ~32 MPG | ~£36 | ~£72 |
| Hybrid (e.g. Toyota Corolla) | ~52 MPG | ~£22 | ~£44 |
| Diesel (e.g. Octavia TDI) | ~52 MPG | ~£27 | ~£54 |
| Large diesel SUV | ~38 MPG | ~£37 | ~£74 |
| Electric (home charging, 3.5 mi/kWh) | — | ~£20 | ~£40 |
Based on 156.8p/litre petrol, 188.8p/litre diesel, 24p/kWh home electricity. May 2026.
Per person cost: With 4 people in the car, a typical family petrol car costs just £7.63 per person each way — significantly cheaper than train tickets, which often cost £40-80+ per person for the same journey.
How speed affects your fuel cost to Cornwall
The M4 and M5 make up the majority of the journey — and your motorway speed has a significant impact on fuel cost. Here's how it breaks down for a typical 38 MPG car:
| Motorway speed | Fuel cost (one way) | Journey time | vs 70mph |
|---|---|---|---|
| 60 mph | ~£26 | ~5h 30m | Save £4.50 |
| 70 mph (limit) | ~£30.50 | ~5h 00m | — |
| 80 mph | ~£35 | ~4h 35m | Cost £4.50 more |
Driving at 80mph instead of 70mph saves about 25 minutes on the journey but costs an extra £4.50 in fuel each way. Over a return trip that's £9 extra — worth thinking about.
Cheapest places to fill up on the route
Motorway services on the M4 and M5 are typically 10-15p per litre more expensive than supermarket forecourts. The best strategy is to fill up before you join the motorway or exit briefly to fill up at a supermarket en route.
Avoid filling up at motorway services if possible. Gordano Services (M5), Leigh Delamere (M4), and Membury (M4) are all convenience stops but can charge 15p/litre more than a nearby Tesco or Sainsbury's. Use our Fuel Finder to see live prices before you stop.
Good cheaper alternatives en route:
| Location | Why stop here | Typical saving vs motorway |
|---|---|---|
| Slough / Reading (M4 junctions 6-12) | Tesco, Asda nearby | 8-12p/litre |
| Bristol area (M5 junction 19-21) | Multiple supermarkets | 10-15p/litre |
| Taunton (M5 junction 25) | Last cheap stop before A30 | 8-12p/litre |
| Exeter (A30 junction) | Sainsbury's, Tesco nearby | 8-15p/litre |
London to Cornwall vs train — cost comparison
| Car (4 people) | Train (per person) | Train (4 people total) | |
|---|---|---|---|
| London to Newquay | ~£30.50 fuel | £40-120 | £160-480 |
| Cost per person | ~£7.63 | £40-120 | — |
| Journey time | ~5 hours | ~5-6 hours | — |
For families, driving is almost always significantly cheaper than the train. Even accounting for parking costs at your destination, the car usually wins on cost for groups of 3 or more.
Tips for saving money on the drive to Cornwall
A few things that make a real difference on a long journey like this:
Fill up before you leave London — fuel in London is slightly cheaper than along the route. Use our Fuel Finder to find the cheapest station near your starting point.
Travel early or late — avoiding peak traffic reduces stop-start driving, which wastes fuel significantly. The M4 and M25 in rush hour can add 30-60 minutes and noticeably increase fuel consumption.
Check tyre pressure — under-inflated tyres increase fuel consumption by 1-3%. Worth checking before a long trip.
Use cruise control on the motorway — maintaining a steady speed uses less fuel than constant acceleration and braking.
Calculate your exact fuel cost for this journey — free