Atlantic Highway fuel cost.
Budget the 70-mile A39 Atlantic Highway from Barnstaple in North Devon to Fraddon in Cornwall. See live South West petrol and diesel prices on the map, then calculate your fuel cost — including the summer-congestion penalty that makes an August run far pricier than the brochure suggests.
Loading nearby stations… or click My Location / search a town or postcode.
Quick answer: Driving the 70-mile A39 Atlantic Highway costs approximately £11 to £15 in fuel for a standard family car — around £11 for a 40 MPG car at average pump prices. In peak summer, heavy holiday traffic around Bude and Wadebridge can add up to 15% to your fuel bill. Despite the name, the A39 is mostly a single carriageway, not a fast dual carriageway. Use the live map above to find the cheapest station before you head into the South West.
How much does it cost to drive the Atlantic Highway?
Driving the 70-mile Atlantic Highway on the A39 costs approximately £11 to £15 in fuel for a standard family car — about £11 for a 40 MPG car at average pump prices. During peak summer months, heavy congestion can push that 15% higher.
The route links Barnstaple in North Devon to Fraddon in Cornwall, passing close to world-class surf beaches and rugged cliffs. It's a staple of UK domestic holidays, which is exactly why August fuel costs run above the guidebook estimate. Enter your own MPG and today's live price in the calculator below for a precise figure.
Is the Atlantic Highway a dual carriageway?
No — the A39 is predominantly a winding single carriageway, not a multi-lane expressway. Limited overtaking and frequent bottlenecks around towns like Bude and Wadebridge mean fuel economy is often lower than your car's stated combined figure.
Many visitors assume a road called a "highway" will be fast. It isn't. Detours to coastal villages such as Clovelly or Tintagel add extreme gradients — Porlock Hill nearby is one of England's steepest — which further hit economy. Plan for a slower, thirstier drive than the mileage alone suggests.
How does summer traffic affect fuel economy in Cornwall?
The summer influx of holidaymakers and caravans creates severe stop-start traffic around key junctions, and constant idling and low-gear acceleration can cut fuel efficiency by up to 15%.
That's the difference between a £13 run in April and a £15+ crawl in August. Tick the summer-congestion box in the calculator to model it. To avoid the worst, fill up before you arrive: Barnstaple, Bideford, Bude and Wadebridge have the reliable forecourts, and supermarket prices there beat the small independent stations in the tourist hotspots. Search a postcode like EX23 (Bude) on the map above.
Calculate your Atlantic Highway fuel cost
Enter your car's MPG, the distance (70 miles for the full A39, or more with beach detours) and today's live price from the map. Tick the box to add the peak-summer congestion penalty.
Formula: (miles ÷ MPG) × 4.546 × (price ÷ 100) — 4.546 is litres per imperial gallon.
Driving the South West for work in your own car? Claim the HMRC Approved Mileage Allowance Payment: 45p per mile for the first 10,000 business miles, 25p thereafter — see GOV.UK simplified expenses.
Which fuel does your vehicle need? A plain-English guide
The live map above covers all six fuel grades tracked under the GOV.UK Fuel Finder scheme. Here's what each one means — and how to choose at the pump before you set off.
The default pump for most petrol cars. Contains up to 10% ethanol. A small number of older or classic cars require E5 — check your handbook before filling.
Higher octane (97–99 RON) and cleaner-burning. Typically 10–20p/litre more expensive. The protected grade for older engines not approved for E10 — and popular with performance cars.
The default diesel pump. Contains up to 7% biodiesel. Suitable for all diesel passenger cars, vans and most HGVs. Generally 2–8p/litre cheaper than premium diesel at the same station.
Includes detergent and cetane-boosting additives. Sold as BP Ultimate Diesel, Shell V-Power Diesel and similar. Use the Premium Diesel toggle to compare the price gap near you.
Contains up to 10% FAME biodiesel — higher renewable content than B7. Only suitable for vehicles whose manufacturer explicitly approves B10. Always check your handbook first.
Drop-in renewable diesel with up to 90% lower lifecycle carbon than fossil diesel. Compatible with most modern diesels — check your handbook. Use the HVO filter above to find nearby stations.
Where should you refuel on the A39?
Fill up in the larger towns at each end and along the route — supermarket forecourts there are far cheaper than the independent stations in the coastal resorts.
Widest choice of supermarket fuel before the A39 heads west — fill up here.
The main refuel point on the Cornwall border, and a notorious summer bottleneck — expect queues in August.
Steep coastal detours with little or no fuel — top up on the A39 first before dropping down to the coast.
Supermarket forecourts near the A30 junction at the southern end of the route.
Two things the tourism boards rarely admit, both answered here: the A39 is not a dual carriageway — it's a mostly single-carriageway road that bottlenecks around Bude and Wadebridge — and peak-summer congestion cuts fuel efficiency by roughly 15% on the 70-mile route. For live prices anywhere in Devon and Cornwall, this page shares the GOV.UK dataset behind our UK-wide fuel map.
Atlantic Highway fuel questions
Related tools & routes
Planning fuel for another drive, or the wider cost of your trip? These help.
Data & estimate disclaimer: Live fuel prices are sourced from the GOV.UK Fuel Finder API under the Motor Fuel Price (Open Data) Regulations 2025. While every forecourt is legally required to report price changes within 30 minutes, CalculatorDashboard.com does not guarantee the accuracy or completeness of third-party data — always verify the displayed price at the pump before fuelling. Journey fuel-cost figures are estimates only: real-world consumption varies with driving style, load, weather and traffic, and quoted route distances and MPG penalties are approximate. HMRC advisory rates are shown for guidance and change quarterly — check the official rate before submitting a claim. Not financial or tax advice. CalculatorDashboard.com is not affiliated with any fuel retailer, supplier or government body.