• Data from HonestJohn.co.uk reveals the UK’s most efficient cars
  • Japanese brands are the fuel economy stars
  • Over a quarter of a million drivers share their real-world MPG numbers
  • Suzuki leads petrol car numbers, Toyota is star hybrid brand and Nissan leads diesel mpg

Unless you drive a fully electric car, stopping at filling stations to buy fuel is one of motoring’s unavoidable costs – but thanks to HonestJohn.co.uk’s Real MPG data, you can make a more informed choice about which model is best for you when it comes to keeping your fuel costs down. 

HonestJohn.co.uk’s Real MPG figures are compiled from information supplied by over 250,000 of the sites readers, split across different models from the whole spectrum of makes, models, sizes, ages and prices. The higher the number achieved, the lower those fuel bill. 

Based on the latest Real MPG results it’s clear that cars from ToyotaSuzuki and Nissan are proving to be among the most economical on Britain’s roads.

Smaller, lighter cars tend to provide the best MPG figures but that doesn’t mean you’ll need to crowbar yourself in a city-centric model to benefit. HonestJohn.co.uk’s  analysis confirms that many family cars will deliver impressive fuel efficiency in excess of 50mpg, while the very best in our lists below all beat 70mpg.

Petrol cars are by far the most prevalent on British roads at the moment, and Japanese maker Suzuki took the top three Real MPG places for petrol models. The 2015-19 Celerio 1.0 DualJet city car came out on top with a score of 70.1mpg, with the 2016-19 Baleno DualJet in second place at 63.5mpg. Third place went to the 2017-24 Swift 1.0 BoosterJet Hybrid.

The best-performing diesel car was the 2017-2022 Nissan Micra dCi 90, which achieved 69.6mpg in Real MPG scoring, followed by the SEAT Ibiza 1.4 TDI Ecomotive with 66.5mpg. In third place was the 2012-2025 Fiat Panda 1.3 MultiJet, with 66.4mpg overall.

Topping the charts for hybrid cars was Toyota, with the 2021 Yaris Cross 1.5 VVT-i Hybrid achieving a Real MPG figure of 70.5mpg. The 2020-on Yaris Hybrid was a close second at 69.6mpg, with the Suzuki Swace (2021-25) in third place at 65.5mpg.

Getting real-world figures for plug-in hybrid models is more complex, as their fuel economy performance is subjective to how the cars are used, but Real MPG data comes from real-world use, so is from authentic users. The top performing plug-in hybrid among HonestJohn.co.uk readers was the 2017-22 Toyota Prius 1.8 VVT-i Plug-in, with a Real MPG figure of 133.5mpg.

The Hyundai Ioniq 1.6 GDI Plug-in Hybrid came in second, with 129.5mpg, followed by the 2014-2020 Audi A3 Sportback 1.4 TFSi e-tron, which achieved 107.3mpg. 

David Ross, HonestJohn.co.uk Senior Editor, said: “Vehicle manufacturers use a standard process to arrive at MPG figures, known as the Worldwide Harmonised Light Vehicle Testing Procedure, or WLTP. While it is said to closely replicate real-world usage, it’s only in daily use when you can truly assess how economical a car really is, and the Real MPG data has shown us some clear differences between WLTP figures and those achieved by HonestJohn.co.uk readers. One thing is certain, though, and it’s that Japanese brands came out on top for Real MPG performance”. 

Although electric cars are growing in number, the range data isn’t yet broad enough to provide a fair comparison. However, HonestJohn.co.uk will launch Real Range soon, based on data gathered from the site’s electric car owners.

A full breakdown of the Real MPG data can be found herehttps://www.honestjohn.co.uk/guides/best-mpg-cars/

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