Snowdonia 360 fuel cost.
Budget the 360-mile Eryri (Snowdonia) 360 loop, or the shorter, steeper internal mountain passes. See live North Wales petrol and diesel prices on the map, then calculate your fuel cost — including the economy penalty on climbs like the Llanberis Pass — and find where to refuel around the national park.
Loading nearby stations… or click My Location / search a town or postcode.
Quick answer: The full 360-mile Eryri (Snowdonia) 360 route needs roughly 41 litres of fuel, costing around £59 in a 40 MPG car (about £60–£70 at typical Welsh pump prices). It covers the whole national park perimeter, the Llŷn Peninsula and Anglesey. The shorter internal mountain loop is about 80 miles, but steep passes like the Llanberis Pass (A4086) cut economy by 15–20%. Refuel in coastal towns like Bangor and Caernarfon, not remote mountain villages. Use the live map above for today's cheapest station.
How much fuel do you need for the Snowdonia 360?
The full 360-mile Eryri (Snowdonia) 360 route requires approximately 41 litres of fuel, costing around £59 in a 40 MPG car — closer to £60–£70 at higher Welsh pump prices. This covers the entire perimeter of the national park, the Llŷn Peninsula and Anglesey.
There's an important distinction most searchers miss: the official Snowdonia 360 is a 360-mile perimeter route, not the short internal mountain passes people often mean. If you're only driving the central passes, that's roughly an 80-mile loop — change the distance in the calculator to match the drive you're actually doing.
Does driving the Llanberis Pass use more petrol?
Yes — the steep inclines of the Llanberis Pass (A4086) can reduce fuel efficiency by 15% to 20% compared with flat coastal driving on the North Wales expressway, because the climbs demand high revs and low gears.
The same applies to the A498 through Nant Gwynant and the other high passes threading Eryri's peaks. If your route takes in the mountain climbs rather than the coastal perimeter, tick the steep-pass penalty in the calculator to see a realistic figure. There's no fuel on the passes themselves, so arrive with a comfortable margin.
Where should you refuel in North Wales?
Coastal towns like Bangor and Caernarfon offer cheaper supermarket fuel. Don't wait until you're deep in the national park, where mountain villages have few stations and higher prices.
Betws-y-Coed is the main inland hub and a useful top-up point, but it gets congested and prices are higher than the coast. The practical rule for Eryri is the same as any mountain region: fill up on the coast or at the edges, then head inland. Search a postcode like LL55 (Caernarfon) or LL24 (Betws-y-Coed) on the map above and sort by cheapest.
Calculate your Snowdonia fuel cost
Enter your car's MPG, the distance (360 miles for the full Eryri loop, or about 80 for the internal passes) and today's live price from the map. Tick the box to add the steep-pass economy penalty.
Formula: (miles ÷ MPG) × 4.546 × (price ÷ 100) — 4.546 is litres per imperial gallon.
Driving North Wales 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 are the fuel stops around Eryri?
Fuel is on the coast and at the park's edges, not deep in the mountains. Here are the reliable refuel points around the Snowdonia 360.
Cheapest supermarket fuel in the region and the gateway to the Llŷn Peninsula and Anglesey.
The main central stop and a key traffic pinch-point; handy but pricier than the coast.
Limited village fuel near the mountain climbs — top up before tackling the A4086 or A498.
Forecourts serving the southern perimeter of the loop and the coast road back north.
The two facts to hold onto, both answered here: the official Eryri 360 route is exactly 360 miles (not the short internal passes people confuse it with), and driving those internal passes like Llanberis cuts fuel economy by 15–20%. For live prices anywhere in North Wales, this page shares the GOV.UK dataset behind our UK-wide fuel map.
Snowdonia fuel questions
Related tools & routes
Planning fuel for another mountain 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.