Real-world MPG: most efficent small petrol cars

  •  We name the most efficient small petrol cars
  •  Mazda 2 just tested
  •  Results indicate real-world fuel economy


We test new cars’ fuel economy every week at What Car?, but unlike the laboratory-derived government data, our True MPG technicians gain the numbers from driving in real-world conditions, to bring you realistic MPG figures.

The Mazda 2 and the Hyundai i20 are the latest cars to get assessed by our testers, and the Mazda does well enough to slot into this list. The i20 misses out with a 42.3mpg True MPG figure, but the 2 does better, with 50.8mpg, and fits into fifth place.

1. Peugeot 108 1.0 VVT-i - official mpg 68.9 True MPG 54.6mpg

The 108 and the Aygo are two of the newest and smallest cars on this list, so it makes sense that they are the most economical. They are not up with their rivals in other areas, however, and the 108's 1.0-litre engine struggles to get going. It is a noisy car when it is on the move as well, with the wind, engine and road all making the cabin a noisy place to be.

2. Toyota Aygo 1.0 VVT-i - official 65.7mpg True MPG 54.0mpg

The Aygo suffers from the same issues as the 108 in terms of refinement and power, but it certainly helps move the game on in terms of economy. It is a shame that the figure is so short of its official rating, though.

3. Mitsubishi Mirage 1.2 – official 65.7mpg True MPG 53.4

Every version of the Mitsubishi Mirage emits less than 100g/km of CO2, and the little car performs admirably in our real-world economy tests as well. Unfortunately, that is about the only strong point for the Mirage, as it falls short of the competition in almost every other area.  

4. Suzuki Swift 1.2  – official 50.0mpg True MPG 51.7mpg

The Swift offers great value for money, and our MPG tests show it should be reasonably cheap to fuel, too. In 1.2 guise it managed 51.7mpg in the hands of our technicians, which is 1.7mpg better than its official figure.

5=. Mazda 2 1.5 Skyactiv-G 89 – official 62.8mpg True MPG 50.8mpg

The Mazda 2 falls a fair way short of its official fuel economy, but a True MPG result of 50.8mpg is still a commendable result in the real world. The engine tested here is the middle of the three power outputs, with 89bhp from the 1.5-litre petrol.

5=. Vauxhall Corsa 1.2i – official 51.4mpg True MPG 50.8mpg

The 1.4-litre Corsa is a better buy, but if efficiency is top of your priorities the 1.2 is one of only a few cars on this list that beats 50mpg. It recorded 50.8mpg in our tests, just 0.6mpg shy of the government data.

7. Toyota Yaris 1.5 Hybrid – official 76.3mpg True MPG 47.7mpg

The petrol-electric Yaris is one of the cheapest hybrids you can buy. While we found a huge 28.6mpg departure from its official MPG figure, the 47.7mpg it achieved is still enough to earn it a place in the top six.

8. Audi A1 1.4 TFSI Sport – official 53.3mpg True MPG 46.9mpg

The A1 is one of our favourite small cars, and this trim is our pick of the range. The 1.4-litre engine is fast and flexible, and returned an impressive 46.9mpg along our test route.

9. Kia Rio 1.25 1 Air – official 56.6mpg True MPG 46.4mpg

The 1.1-litre diesel Rio is one of the most efficient cars we’ve tested, but its petrol sibling won’t break the bank either. In fact, the 1.25 Air is the model we recommend from the range. It achieved 46.4mpg in our True MPG tests, which is 10.2mpg lower than its official figure.

10. Ford Fiesta 1.0 Ecoboost 125 – official 65.7mpg True MPG 46.2mpg

The Fiesta is the UK’s best-selling car, and this is the most efficient petrol version you can buy. The government test result is a lofty 65.7mpg, but in our real-world driving it managed 46.2mpg.

Visit to see the full range of cars we’ve tested to find out what you really can expect to achieve on UK roads.


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