Best cars with low CO2 emissions

You don't have to go electric to get a low-emission car – there are plenty of hybrids and efficient diesel models with low CO2 emissions

BuyaCar team
Jul 27, 2022

Car manufacturers are under ever-increasing pressure to reduce the CO2 emissions of the cars they produce. Eventually, car companies will have to get rid of their petrol and diesel models entirely, but for now, cars with combustion engines are becoming ever more efficient and less polluting.

The good news is, reducing your emissions doesn't mean you have to drive something slow and boring, there is still plenty of enjoyment to be had from behind the wheel of a car producing fewer than 100g/km of CO2. In fact, you don't really have to sacrifice anything. As our list below proves, you can drive a hefty SUV, a smart saloon or a practical diesel estate car and still have a car that fits into the low-emissions bracket.

What’s more, these clean-living cars also offer lower rates of road tax (for those registered before April 2017), while their frugal nature helps to reduce your fuel costs. And with many of these used cars being available on BuyaCar from much less than £10,000 or under £200 per month on PCP finance, you could make some serious savings while feeling much better about your carbon footprint.

So read on for our selection of 12 excellent family-friendly cars with low CO2 emissions that are all available used for less than you might think.

Best cars with low CO2 emissions

1. DS 3

Best low CO2 car for style on a budget

Our pick DS 3 PureTech 110 S&S
Used deals from £6,940
Monthly finance from £132*
 CO2 emissions 100g/km
Fuel economy 65.7mpg

DS is Citroen's upmarket brand and as a result, the DS 3 features a lot of Citroen DNA, including funky styling and punchy engines. The Mini-rivalling DS 3 lets you style it out on a budget and cut your CO2 emissions in the process.

That’s because it features a clever PureTech engine, which offers up an impressive mix of economy and power. This small petrol engine sips fuel at a rate of up to 65mpg - meaning your fuel bills should be low - yet never feels underpowered, offering more punch than you'd expect. It sounds a little sporty, too, and pulls enthusiastically from low engine speeds, making light work of day-to-day driving.

Outside of this, the DS 3 is a good-looking car that turns more heads than most cars of this type. We'd recommend opting for the Parthenon Cream trim level for the optimum blend of stylish design and frugal motoring.


2. Ford Fiesta

Best low CO2 car for all-round appeal

Our pick Ford Fiesta 1.5 TDCi 85hp
Used deals from £6,600
Monthly finance from £148*
 CO2 emissions 82g/km
Fuel economy 74.3mpg

Small cars and diesel engines are an increasingly rare combination. Carmakers are slimming down their model ranges, arguing that consumer demand and efficiency improvements in petrol engines mean there’s no longer the need for diesel in small cars. 

However, pair the previous version of the Fiesta with the 85hp version of the 1.5-litre diesel engine and it emits just 82g/km of CO2 and can make each forecourt fill-up last further than most cars, thanks to a strong claimed fuel economy figure of 74mpg. These figures were arrived at under the previous testing cycles, rather than the new WLTP tests, which means they're very optimistic. You can still expect upwards of 50mpg.

The driving experience remains impressive - the Fiesta is one of the most fun to drive cars of any size or price. However, some rivals, including the Seat Ibiza and Volkswagen Polo offer more classy and comfortable interiors. But if you can live with a slightly less exciting interior - or pay a little more to get the latest version - the Fiesta won’t disappoint.


3. Audi A1

Best low CO2 car for a posh badge at an affordable price

Our pick Audi A1 30 TFSI
Used deals from £15,699
Monthly finance from £234*
 CO2 emissions 108g/km
Fuel economy 58.9mpg

The second-generation Audi A1 was launched in 2018, and it’s a rather handsome-looking thing. But more significantly, you’re getting an upmarket small car at an affordable price, something neither BMW nor Mercedes can offer.

With the entry-level 30 TFSI petrol engine fitted, the A1 is one of the cleanest small petrol cars going - especially if you want one that comes with added wow factor. It emits just 108g/km and can achieve nearly 59mpg, and all the while the three-cylinder turbocharged engine is smooth and gives a spritely turn of speed.

Although the Mini Cooper and Ford Fiesta are a little more fun to drive, they can’t match this car’s high-quality feel. The classy and strikingly designed interior is somewhere drivers will be very happy to spend time racking up the miles.



4. Toyota Yaris

Best low CO2 car for city driving

Our pick Toyota Yaris Hybrid
Used deals from £10,490
Monthly finance from £209*
 CO2 emissions 84g/km
Fuel economy 76.3mpg

With emissions of just 84g/km, the hybrid-powered Toyota Yaris is the car to turn to if all you care about is having a petrol-powered run-around for town driving with the lowest possible emissions.

And with a hard-earned reputation for reliability, Toyota’s self-charging hybrid system shouldn’t be dismissed by those who have never owned this type of car. It’s straightforward to drive and doesn’t require anything from the driver; you simply drive as normal and the car takes care of everything, from recharging the battery - which is used to power the electric motor - to deciding when to rely on the petrol engine or the electric motor and when to combine the two. If the Yaris is too small for you, there are plenty of other efficient Toyota hybrid models to choose from with similar setups.

Another plus point is that the Japanese carmaker provides a ten-year warranty as standard, but this was previously five years so don't expect a nine-year-old Toyota to have one year of its warranty remaining. Given the hybrid system’s reputation for reliability, though, most owners won't have to call on the long warranty.


5. Audi A4

Best low CO2 car for relaxing driving

Our pick Audi A4 2.0 TDI ultra
Used deals from £12,000
Monthly finance from £238*
 CO2 emissions 99g/km
Fuel economy 74.3mpg

Want a car that will make you feel relaxed? The Audi A4 represents the German brand at its best, as a wonderfully quiet and comfortable car that can make a 1,000-mile journey seem like a quick trip to the shops.

The 2.0-litre diesel engine is barely audible, the noise of the tyres and sound of the wind around the front of the car hardly make it inside, and the seats do a first-class job of keeping aches and pains at bay.

Choosing the 2.0-litre diesel model in ‘ultra’ specification and the 17-inch alloy wheels - which are smaller and lighter than the ones of some other versions - enables this relatively large car to prove surprisingly frugal and clean. Its CO2 emission figure of just 99g/km is low for this type of car, but you won't feel like you're having to make any compromises from behind the wheel.


6. Ford Focus Estate

Best low CO2 car for carrying cargo

Our pick Ford Focus Estate 1.5 EcoBlue 95hp
Used deals from £10,400
Monthly finance from £224*
 CO2 emissions 96g/km
Fuel economy 78.5mpg

When it comes to carrying luggage, it’s hard to beat a good estate car. Being lower to the ground than an SUV is just one of the benefits, which means putting in the pet pooch or loading up luggage in the boot is far easier. And with 575 litres of space, or 1,620 litres when the seats are lowered, the Ford Focus Estate is more than capable of making light work of family life.

To achieve the lowest level of emissions with this estate, however, you’ll need to choose the smallest and least powerful version of Ford's 'EcoBlue' diesel engine. Go for this engine and the Focus is no sports car - 0-62mph takes nearly 12 seconds, and that’s before all the seats are filled with passengers and the boot’s bursting with luggage.

Still, the engine offers a good spread of power and if you don't feel the need to drive at full speed everywhere, it's a great family car. It's enjoyable to drive, packed with useful technology and safe, which makes it a strong all-rounder that gives the Volkswagen Golf a run for its money.


7. Hyundai Ioniq

Best low CO2 car for ultra-low emissions

Our pick Hyundai Ioniq Hybrid
Used deals from £14,995
Monthly finance from £274*
 CO2 emissions 79g/km
Fuel economy 83.1mpg

Think hybrid car and the chances are you’ll think of the Toyota Prius. But since 2016, Hyundai has been muscling in on the Toyota's patch, with the Ioniq. Available as a hybrid, a plug-in hybrid (which has a larger battery pack but requires you to charge it regularly to get the full benefit from this) or an electric car. The most basic hybrid is a good starting point at a competitive price.

Its eco-credentials speak for themselves: CO2 emissions are 79g/km if you choose a version with 17-inch alloy wheels, and there is the potential for 83mpg. In other words, it competes very closely with the Prius and you can expect very low fuel bills for this size of car.

Unlike its main rival, however, the Ioniq looks relatively normal and has a smarter interior. And when you factor in the price, which will save you several thousands of pounds, the Korean contender from Hyundai looks like a smart choice.


8. Mercedes A-Class

Best low CO2 car for slick in-car tech

Mercedes A-Class front three quarters view

Our pick Mercedes A180d SE
Used deals from £15,000
Monthly finance from £213*
 CO2 emissions 108g/km
Fuel economy 68.9mpg

Mercedes went to town on the interior design and in-car technology of the A-Class. The designers and engineers figured that this is where customers could really appreciate the difference between the A-Class and, say, a VW Golf or Audi A3.

And what a difference. The interior of the Mercedes A-Class stands out from its peers with a seven-inch digital instrument display that sits on a panel that extends to the centre of the dashboard via a seven-inch touchscreen media system.

This is livened up with neat touches such as air vents that are illuminated and can change colour at the touch of a button, while the tech includes Mercedes' voice-controlled virtual assistant, called MBUX, which means you can issue voice commands to set the sat-nav address, for instance, allowing you to keep your eyes on the road rather than forcing you to prod the screen.

Stick to the entry-level A180d diesel version and the emissions are low. However, if you can stretch to the A200d, give it some thought as it’s barely any less efficient but offers notably more performance, so if you'd value extra power with just a small economy penalty, it's a good choice. The A-Class was one of the first Euro 6-compliant cars when it was new, so you can be fairly sure of its eco-credentials.


9. Nissan Qashqai

Best low CO2 car for value for money

Nissan Qashqai front three quarters view

Our pick Nissan Qashqai 1.5 dCi 115
Used deals from £9,250
Monthly finance from £163*
 CO2 emissions 100g/km
Fuel economy 74.3mpg

SUVs are all the rage and when it comes to getting good value for money, the Nissan Qashqai is hard to beat as a used model. It's a solid all-rounder, with used prices on BuyaCar starting from £187 per month for the most economical 1.5-litre diesel, which is pretty competitive pricing.

Putting your finger on the ‘value’ element requires a bit more than looking at the price and specifications, though. Drive the Qashqai and you’ll be pleased to find it’s refined, with little engine or road noise, while the suspension provides a smooth ride.

The interior may not be the most stylish or original, but there’s lots of space for a family, especially in the back seats. The boot could be bigger and there’s no longer the option of extra seats in the back but Nissan has an answer, in the form of the larger X-Trail SUV, which is available with seven seats.


10. Citroen Grand C4 SpaceTourer 

Best low CO2 SUV for carrying seven passengers

Our pick Citroen Grand C4 SpaceTourer BlueHDI 130 S&S EAT8 auto
Used deals from £14,900
Monthly finance from £277*
 CO2 emissions 105g/km
Fuel economy 70.6mpg

The original C4 Picasso was no oil painting, prioritising practicality over style, but the third-generation model came good - ironically just as Citroen stopped using the Picasso name and switched to ‘C4 SpaceTourer’.

It’s one of the most comfortable people carriers going, and even if you pile seven people aboard, it will cope admirably. If there are just five of you, then the boot holds up to 630 litres of shopping and pushchairs or a holiday’s load of luggage.

With the 130hp diesel engine fitted along with the eight-speed automatic gearbox, you can sit back and relax as the car takes the strain and makes effortless progress, while the emissions are exceptionally low for a seven-seat diesel car of this size. A comfortable ride from the suspension is an added bonus.


11. Skoda Superb Estate

Best low CO2 car for interior room

Skoda Superb Estate front

Our pick Skoda Superb 2.0 TDI 150 SCR
Used deals from £14,000
Monthly finance from £254*
 CO2 emissions 115g/km
Fuel economy 64.2mpg

It’s risky business naming a car Superb, but this one’s good enough to pull it off without being ridiculed. The clever thing about Skoda’s largest hatchback and estate is that although this is a very large car, it never feels unwieldy. It's responsive to drive, the ride is exceptionally comfortable and refinement is impressive.

When you carry passengers, you can expect to be paid compliments about the comfort of the back seats and the amount of space in which to stretch out; this is a vast car with as much room in the back as some seriously expensive luxury cars. And if you have children, this means that they won’t be elbowing one another and bickering over seat space - regardless of whether they're toddlers or teenagers.

Skoda recently stopped selling the 1.6-litre diesel engine in its Superb range, which is a great shame as it was especially frugal. However, the 2.0-litre diesel is still a good buy, and with emissions of 115g/km from one of the most spacious estate cars on the road, it’s still a great package.


12. Toyota C-HR

Best low CO2 car for SUV style

Our pick Toyota C-HR Hybrid
Used deals Limited stock
 CO2 emissions 86g/km
Fuel economy 74.3mpg

If you like to be different, then the Toyota C-HR has a lot to offer. It stands out from the crowd with an edgy design and under the bonnet is a hybrid system that’s still a rarity in small SUVs.

The combination of a 1.8-litre petrol engine and battery-powered electric motor is well proven by Toyota; the company has sold more than 10 million Toyota and Lexus hybrids to date. The silent running of the electric motor gives this car an appealing level of refinement, while the combined power of the engine and motor match a diesel for performance.

The emissions are impressively low, and there are far fewer associated pollutants if you choose this over a diesel equivalent. And in our experience, it should match the fuel economy of a comparably sized, diesel SUV.


*Representative PCP finance - Ford Fiesta:

48 monthly payments of £192
Deposit: £0
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
APR: 9.9%

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.


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