Average MPG for Cars UK (2025)

While not everyone realises it, buying a car with great fuel efficiency can be a fantastic way to save on the annuals costs to run a car, especially if you put a lot of miles on your car—most car owners spend around £1,000 on fuel each year. How many miles does the car get between each visit to the petrol station—and is that level of fuel efficiency any good?

Below we've calculated the average miles per gallon (mpg) for petrol and diesel cars—and miles per gallon equivalent (MPGe) for hybrid and electric cars—to give you a benchmark for understanding how fuel efficient any given car is. While buying a car with better fuel economy is the best way to save money at the pump, you can also read our top tips for improving fuel efficiency in your vehicle.

Average Miles per Gallon

The average MPG for cars in the UK is 38.6 miles per gallon. Fuel efficiency varies by type of fuel, however, with petrol cars getting 36 mpg and diesel cars getting 43 mpg. In contrast, the average UK all-electric car gets a whopping 80 MPGe.

To determine average miles per gallon, we analysed real-life user data from Spritmonitor, which enables users to track and calculate fuel efficiency for their personal cars. The resulting database contains over 30 million fuel ups for over 800 thousand vehicles. From this database, we extracted real-life fuel usage data from the past year for petrol, diesel, hybrid and electric cars.

In contrast to cars, the fuel efficiency of motorcycles is much better—the average motorcycle get 56.7 mpg!

Most Efficient UK Electric Cars

Tesla has the most energy efficient cars in the UK market, namely the Model 3 (Efficiency: 221 Wh/mi). The Mini Cooper Electric SE is next most energy efficient, with an efficiency rating of 240 Wh/mile. The Hyundai IONIQ 6 Long Range 2WD ranks third with efficiency of 243 Wh/mile.

The least energy efficient EV vehicles in the UK market are produced by Mercedes: the Mercedes Benz G 580 (Efficiency 527 Wh/mi) and the Mercedes Benz EQV 300 (Efficiency 462 Wh/mi). With starting OTR prices of £181K and £94K, these cars are not for the masses anyway.

FAQs

Methodology

Spritmonitor database entries are stored as litres/100km for petrol and diesel cars and kWh/100km for electric cars. For use in the UK, we converted these values into miles per gallon (Imperial) or a miles per gallon equivalent (MPGe) for electric cars. To calculate the overall miles per gallon metric, we took a weighted average of petrol and diesel figures using the number of petrol and diesel cars in the UK.

To calculate MPGe for electric cars, we calculated how many miles a car can drive on average for an amount of electricity that's equivalent in cost to a gallon of fuel. Here are the average fuel costs we used:

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