Top 9 most economical cars 2024

With unpredictable fuel prices and a growing need to reduce our carbon emissions, it makes sense that fuel economy is often a top priority for car buyers. Today’s engines are more efficient than ever before, but finding official fuel-efficiency figures for each make and model can be a laborious task. With that in mind, we’ve rounded up the most economical cars on sale today, so look no further if you’re after rock-bottom fuel bills.

Our list focuses on models with the most economical petrol, diesel and plug-in hybrid cars on the market – if you’d rather read about pure electric models that could cost even less to run, we’ve got lists where we round-up the best electric cars, cheapest electric cars and the longest-range electric cars.

For simplicity, we’ve listed the most economical petrol cars first, followed by the diesel cars with the highest miles per gallon results in official WLTP testing. After these, we’ve also included plug-in hybrid models, which tend to offer the highest MPG figures out of any cars on sale.

Keep reading below to find out which are the most economical cars on sale in the UK.

Most economical petrol cars

1. Mazda2

• Up to 60.1mpg

The petrol-powered Mazda2 is sold alongside the Mazda2 Hybrid, which is based on the Toyota Yaris Hybrid. While the full-hybrid model gets an impressive 74.3mpg figure, the mild-hybrid 1.5-litre E-SkyActiv G 89bhp petrol model we’re focused on here is still the most fuel-efficient petrol car on the market, achieving an excellent 60.1mpg. It’s also much cheaper than the Mazda2 Hybrid, making it a more accessible option for many buyers.

We like the Mazda2 for many reasons aside from its fuel economy. Although it’s been around for some time now and is starting to show it on the inside, the Mazda2 is attractively styled and its sharp handling makes it worthy of the Mazda badge, given the brand’s history of creating fun-to-drive cars. Cars get LED headlights, Bluetooth, cruise control, electric windows, air con and rear parking sensors as standard, so it’s still a fairly well-equipped car despite its age.

2. Suzuki Swift

• Up to 59.7mpg

The Suzuki Swift’s 1.2-litre Dualjet engine is capable of up to 59.7mpg in official tests, taking second place in our most economical petrol cars ranking. This mild-hybrid-assisted engine produces 82bhp and is used across the Swift range, but it’s the entry-level SZ-L that gets the best fuel economy figure.

Although there are more pleasing interiors offered by rivals, the SZ-L is at least well-equipped, and it’s our pick of the range even without considering the great fuel economy figure. This version comes with a seven-inch touchscreen, a DAB radio, Apple CarPlay and Android Auto connectivity, as well as a reversing camera. LED headlights, alloy wheels and air conditioning all feature, too, delivering on what most buyers will need in a supermini.

A new generation of Suzuki Swift is on the way, also using a 1.2-litre mild-hybrid engine. Suzuki claims that it will bring even better fuel economy than the current model, so we expect it to retain a spot on this list.

3. Kia Picanto

• Up to 58.9mpg

Kia’s tiny city car, the Picanto, can deliver equally tiny fuel bills, with a combined fuel economy figure of 58.9mpg. Only the entry-level 1 and 2 trim levels achieve this low fuel consumption, but even the least efficient Picanto still achieves over 50mpg. Not only is it cheap to run, but it's also one of the most affordable cars to buy, starting from around £14,000, as well as being one of the only insurance group one cars on sale.

Of course, with such a money-saving focus, the interior of the Picanto isn’t exactly dripping with luxury, but it’s well-built with enough technology to keep it competitive in its class. More impressive is the practicality; there’s enough space for four adults and the boot is surprisingly big for a car with such a miniscule footprint.

The Picanto is receiving a facelift soon, bringing a sharper look to the exterior. The 1.0-litre engine used in the current model will be carried over, so fuel economy is unlikely to suffer.

Most economical diesel cars

1. Volkswagen Golf

• Up to 67.5mpg

The Volkswagen Golf name is one of the best known on this list – and the 2.0-litre TDI diesel with 113bhp in Life trim is one of the most economical cars on sale. It’s capable of a 67.5mpg fuel economy figure, and you’ll get the slightly premium image associated with the brand, along with a more spacious interior than the superminis also listed here.

The Golf feels good to drive and in Life trim you get standard-fit automatic LED headlights, front and rear parking sensors, 16-inch alloy wheels, and electrically heated and adjustable door mirrors. Plenty of safety tech is also thrown in, including adaptive cruise control, lane-keep assist and road sign recognition tech, but its infotainment has come under fire for being rather fiddly to use.

2. Skoda Octavia

• Up to 67.3mpg

The Skoda Octavia is a Carbuyer favourite for many reasons, including its strong 2.0-litre diesel engine that returns up to 67.3mpg. The engine – and much of the Octavia’s underpinnings – are shared with the Golf above, yet the Skoda returns essentially the same fuel economy in a larger and more practical package. It's not the most exciting of engines, with just 114bhp, but it pulls strongly enough and will happily cruise at motorway speeds.

Historically, opting for a Skoda over a Volkswagen would mean sacrificing interior design and quality for a lower price tag, but that’s no longer the case. The Octavia is just as well-built and well-equipped as its Golf cousin, with class-leading legroom and a vast 600-litre boot, while undercutting it on price. Like the Golf, Skoda will sell you an estate variant or one equipped with a DSG automatic gearbox, although fuel economy will drop marginally.

3. Citroen C3 Aircross

• Up to 63mpg

The comfy Citroen C3 Aircross is a quirky SUV-variant of the regular C3 hatchback, with a 1.5-litre diesel engine that returns up to 63mpg. It’s one of the best diesel engines fitted in a small car today, with 109bhp and a smooth and punchy power delivery. It’s more expensive to buy than the petrol variants, but the fuel-sipping diesel could more than make up the difference for those who cover big motorway miles.

You won’t have any issues covering long distances in the C3 Aircross either. Citroen has clearly prioritised comfort over sportiness, fitting the C3 Aircross with long-travel suspension that deals with bumps more gracefully than a Ford Puma. The cabin feels nice, too, with a simple but stylish layout and a respectable level of standard kit – even the entry-level ‘You’ trim gets air-conditioning, a leather steering wheel and a seven-inch infotainment display with Apple CarPlay and Android Auto.

Most economical plug-in hybrid cars

1. Mercedes GLC

• Up to 706.3mpg

Yes, you did indeed read that correctly. The Mercedes GLC, when ordered in 300 de spec, has an official WLTP fuel efficiency figure of 706.3mpg. It’s one of very few diesel plug-in hybrids on the market, offering a unique and hugely efficient powertrain – as long as you remember to keep the battery topped up for most trips. A 194bhp engine works alongside a 134bhp electric motor, giving drivers the best of diesel efficiency at high speeds, and emissions-free EV driving around town.

The GLC’s interior design wouldn’t feel out of place in the S-Class limousine, with a giant 12.3-inch infotainment touchscreen and expensive-feeling materials everywhere you touch. The big, tall SUV body doesn’t lend itself to a particularly inspiring driving experience, but you get a big boot and bags of passenger space in return. For those who find a regular SUV just too ordinary, the Mercedes GLC Coupe has a sleeker roofline, although it can’t be ordered with the 300 de engine.

2. Mercedes C-Class

• Up to 565mpg

Despite not coming with the diesel plug-in hybrid powertrain of its SUV sibling above, the petrol plug-in hybrid Mercedes C 300 e still achieves a mind-boggling 565mpg. This is thanks to the car’s ability to travel up to 67 miles on electric power alone, according to Mercedes. Like many plug-in hybrids, we think it’s the best car in the lineup to go for as a company car, thanks to its low CO2 emissions putting it into the cheapest BiK band for non-electric models.

Mercedes’ focus is on comfort, rather than driver appeal, and the C-Class certainly delivers on this front – driving in electric mode also makes it even quieter to ride in, which will add to the appeal for some. Mercedes is doing a great job with its latest interiors, and the C-Class is no exception – the design is beautiful and modern, and gives it the edge over rivals. Drivers get a 12.3-inch digital instrument cluster, and the way the car’s 11.9-inch centre infotainment screen displays Android Auto and Apple CarPlay is better than rivals.

3. Mercedes E-Class

• Up to 565mpg

It’s no surprise that the Mercedes E-Class has made it onto this list as it’s available with exactly the same plug-in hybrid petrol engine – with exactly the same MPG figure – as the C-Class. Keep the battery topped up and you’ll be able to manage around 70 miles of pure-electric driving in the E-Class, ideal for those who spend lots of time driving around town but still need a petrol engine for longer journeys.

There’s the same focus on comfort over sportiness that you find in the C-Class, but the longer wheelbase and optional air suspension of the E-Class make the passenger experience even more serene. It’s quieter and more high-tech from behind the wheel, too, with its bank of giant screens illuminating the cabin at night like Times Square. 

Economical car buying guide

Picking one of the most fuel-efficient cars can be very important, as paying for fuel is usually the biggest expense in any annual motoring budget. Thanks to the latest fuel-saving technology, there are plenty of large and small economical petrol, diesel and hybrid cars on sale in the UK.

Where diesel may originally have been the fuel of choice for those seeking the best economy, modern turbocharged petrol engines and hybrids are capable of matching or even beating the economy figures offered by diesel engines. Economical family cars and SUVs are increasingly being offered with hybrid and plug-in hybrid powertrains as diesel sales decline. With higher rates of tax for diesel cars, fuel savings could be outweighed by a bigger tax bill, unless the majority of your driving is on the motorway where diesel offers the biggest economy gains over petrol.

On paper, plug-in hybrid cars seem to be a no-brainer, offering sky-high fuel economy figures well into the 300s and beyond. While these figures have been WLTP tested and serve as a good comparison between different plug-in hybrids, achieving these MPG numbers in the real world is probably impossible for most drivers. 

Only if you spend the majority of your time driving in pure-electric mode, with minimal use of the combustion engine, will you achieve the quoted figure. That being said, keep the battery topped up and drive sensibly, and you could see MPG figures with three digits. There are also tax incentives for some plug-in hybrid cars, so you could end up saving yourself some cash another way.

Check out our best hybrid cars, or see our best family cars.