Best MPG cars 2023
Spend less filling up and cut emissions too: these are the best petrol, diesel, and hybrid cars for fuel economy
Now has never been a better time to consider one of the most economical cars you can buy, with fuel and energy prices at an all-time high and further financial insecurities as we head into the winter and beyond.
There are other benefits, too, like being able to travel a longer distance without needed to fill up, not to mention the environmental benefits of emitting fewer greenhouse gases.
Exactly which type of car is best for you will depend on how (and where) you intend to drive it. A plug-in hybrid suits if you generally take short journeys and can charge up at home, while self-charging hybrids are also well suited to town driving.
Then, there are petrol and diesel engines, sometimes with mild hybrid assistance, which can be cheaper and offer greater fuel economy on a long run in some instances.
Best cars for fuel economy
We've listed the most efficient cars from each group below. The figures are pulled from a database that uses the WLTP testing procedure, which is slightly better than the system it replaced, but the figures it produces should still be taken with a pinch of salt.
If you do opt for diesel, then it's worth ensuring that it complies with the latest emissions standards, known as Euro 6, to avoid additional charges such as the London ULEZ and and other clean air zones. Virtually every new car registered since September 2015 has met this standard.
We’re used to seeing mpg figures exceed 200 for plug-in hybrids because they can complete most of the WLTP testing cycle on electric power, but in reality, with irregular charging even 70mpg can be optimistic. Enter the new C300e, which promises 565mpg.
It uses a large 25.4kWh battery, which is bigger than you’d find in the lower-range Fiat 500 Electric Action. It’ll do a claimed 68 miles on electric power, meaning the majority of your journeys could be done without needing to use the 204hp 2.0-litre petrol engine.
Another entry from Mercedes, the GLE is a large SUV that takes on the BMW X5 which is said to achieve 235mpg in xDrive45e plug-in hybrid form. The GLE 350de uses an even bigger 31kWh battery, but because it’s significantly heavier it’ll only do 58 electric-only miles.
Because it uses a diesel engine (a 194hp 2.0-litre unit), it should prove fairly economical when the battery runs out. It can also tow up to 2,700kg like the other diesel models.
The Niro is available with self-charing hybrid, plug-in hybrid, and electric power, but unlike some other eco-conscious cars, it doesn’t look too outlandish. In fact, we think this second-generation model looks great.
It’s more conventional in that it uses an 11.1kWh battery for an electric range of 40 miles, and when that’s depleted, it’ll likely do around 60mpg just like its self-charging sibling.
More recently, one of Toyota’s major selling points is its warranty. It starts at three years, but can be extended with an annual service all the way up to 10 years. It’s also a comfortable family car that’s especially efficient.
The 1.5-litre petrol engine is smaller than we’ve seen in other hybrid Toyota products like the Corolla and C-HR, which means it’s even more efficient. Its CVT gearbox is best suited for gentle driving, though, because it can cause the engine to be noisy under harsh acceleration.
The Renault Clio is somewhat of a rarity even by today’s standards, as not many superminis come with hybrid power. The 1.6-litre petrol setup is different to most others, too, because it uses two electric motors. One for driving the car at slow speeds and another for smoothing out gear changes.
With some cars, fuel economy can vary depending on the trim you go for, because more equipment adds more weight, thus resulting in a less efficient car. That’s not the case with the Clio, so you can go for whichever model you prefer knowing you’ll be getting the same mpg figures.
While there are other hybrids more economical than the UX, they come from brands that we’ve already covered (namely the Renault Arkana and the Yaris Cross, C-HR, and Prius from Toyota). That said, Lexus and Toyota are part of the same company, so you can benefit from that same 10-year warranty.
It uses a 2.0-litre engine for a total of 184hp, which is slightly less than the more efficient Corolla’s 196hp. In front-wheel-drive format, Lexus claims 53.2mpg. There’s a four-wheel-drive variant and an electric model, too.
One diesel car regularly at the top of the charts for fuel efficiency is the 208. Most buyers opt for the 1.2-litre petrols or the electric version, but the diesel model does have some appeal for long-distance drivers.
It’s the same 100hp 1.5-litre engine used elsewhere in the Peugeot, Citroen, DS, and Vauxhall ranges. Peugeot claims 73.6mpg, and we think in excess of 60mpg is easily achievable in the right conditions.
While recent trends have pointed towards crossovers, hatchbacks still have their place. Especially as they’re typically more aerodynamic, which goes a long way in an era of watching the pennies.
The 2.0-litre diesel engine in the Leon is geared towards efficiency. It only has 115hp, which enables it to get 64.2mpg on official tests. There’s a 150hp version that’s almost as economical, too.
Because most people are choosing petrol over diesel (which currently makes up just 10% of new car sales), diesel engines are mainly found in larger crossovers and SUVs.
The Duster is Britain’s cheapest 4x4, which in diesel form will get 53.3mpg. It’s the front-wheel-drive model that will get the best figures, though, with Dacia claiming 58.9mpg.
1. Toyota Aygo X
For a long time, the Citroen C1, Peugeot 108, and Toyota Aygo were all among the most efficient petrol cars available. They all shared the same engine and many of their parts, however they are no longer available new.
Step in the Aygo X, which replaces the Aygo with a more chunky style designed to appeal to small crossover buyers. Its 72hp 1.0-litre engine is far from quick, but it still tops the charts with 58.9mpg.
2. Ford Fiesta
The Fiesta regularly enters the charts as one of Britain’s best-selling cars, and if it can’t be found there, it can be found as a used car favourite, often in number one position. While it’s due to end production in 2023, there’s life in the Fiesta yet.
In mild hybrid form, the 1.0-litre ‘EcoBoost’ engine with 125hp can do 57.6mpg, making it more economical and more fun to drive than the cheaper 1.1-litre petrol.
3. Seat Ibiza
The 95hp version of the 1.0-litre engine should do 54.3mpg - on paper - but we think it’s worth going for the slightly more powerful 110hp version, which will lose you 2mpg.
*Representative PCP finance - Ford Fiesta:
48 monthly payments of £192
Mileage limit: 8,000 per year
Optional final payment to buy car: £2,923
Total amount payable to buy car: £11,926
Total cost of credit: £2,426
Amount borrowed: £9,500
BuyaCar is a credit broker, not a lender. Our rates start from 6.9% APR. The rate you are offered will depend on your individual circumstances.