Fuel Cost Calculator UK (2025) – Petrol, Diesel & Electric Cost per Mile

Want to know how much it costs to drive in the UK today? This guide explains how to calculate your petrol, diesel, or electric car running costs per mile. Using up-to-date UK prices from 29th September 2025, you’ll find formulas, worked examples, and journey cost tables so you can quickly estimate the cost of your trip.

How to Work Out Fuel Cost Per Mile UK

The calculation is simple. You only need three things:

1. Your car’s fuel efficiency (MPG for petrol/diesel, miles per kWh for EVs).

2. Current fuel price (pence per litre or kWh).

3. The distance you’re travelling.

Formulas:

• Petrol/Diesel: (Fuel price per litre × 4.54) ÷ MPG = Cost per mile

• Electric: Price per kWh ÷ Miles per kWh = Cost per mile

Petrol Cost per Mile UK (2025)

• Petrol price (Sept 2025): £1.47 per litre

• Typical car efficiency: 40 MPG

• Formula: (147p × 4.54) ÷ 40 = ~16.7p per mile

Example: Driving 100 miles in a petrol car costs around £16.70.

Diesel Cost per Mile UK (2025)

• Diesel price (Sept 2025): £1.55 per litre

• Typical car efficiency: 45 MPG

• Formula: (155p × 4.54) ÷ 45 = ~15.6p per mile

Example: Driving 100 miles in a diesel car costs about £15.60.

Electric Car Cost per Mile UK (2025)

• Home charging price (Sept 2025): 28p per kWh

• Typical EV efficiency: 4 miles per kWh

• Formula: 28p ÷ 4 = 7p per mile

Examples:

• 100 miles at home charge = £7.00

• 100 miles on public rapid charge (45p/kWh) = £11.25

For a deeper look at EV efficiency, see our guide: Miles per kWh: EV Efficiency Explained (UK Guide 2025).

Journey Fuel Cost Examples (20, 40, 100, 300 Miles)

This table covers popular searches like 20 miles petrol cost UK, 40 miles petrol cost, and cost of 100 miles petrol UK.

Factors That Affect Fuel Cost Per Mile

Your real-world cost may vary depending on:

• Driving style – smoother driving saves fuel.

• Speed – high speeds lower MPG and EV efficiency.

• Load – heavy cargo or passengers increase consumption.

• Tyre pressure – underinflated tyres reduce efficiency.

• Route – city driving costs more per mile than steady motorway cruising.

Check Options to Save on Fuel

Looking to explore more about reducing your motoring costs? Check out:

• No Deposit Car Leasing – spread the cost without upfront payments

• Electric Car Lease Deals – drive the latest EVs with lower running costs

• Used Electric Car Leasing – affordable way to go electric