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Low emission cars for the ULEZ 2024

  • Parkers picks the best low-emission cars
  • Avoid ULEZ charges with green credentials
  • Cost-saving choices and premium alternatives

Written by Cat Dow Updated: 7 February 2024

With a greater number of UK cities introducing clean air zones (CAZ) or ultra-low emission zones (ULEZ), emissions levels are becoming a bigger factor in car purchasing. Aiming to avoid additional charges and make their driving more environmentally friendly, savvy motorists are looking to buy the best low-emission cars that emit grams of carbon dioxide per kilometre (CO2 g/km) under a particular threshold.

While the most obvious answer might be to finally make the switch to an electric vehicle, such a change doesn’t yet suit every household. There are complaints about the public infrastructure and home charging isn’t as straightforward as perhaps it could or should be. While there is the option of a portable Zipcharge Go charger, such a solution doesn’t come cheap.

The best low-emission cars in 2024

A practical and flexible family PHEV

The Toyota RAV4 PHEV makes this list for finding that difficult balance between quality interior, useful zero emissions mileage and a relaxed comfortable ride.

The 2.5-litre petrol engine is spirited when combined with the electric mode. While it’s not the most polished drive, there’s an engendered sense of safety. With 46 pure-electric miles, cost savings are likely to arrive sooner rather than later

Price new: From £39,875
Price used: From £15,875

To find out more, read our full Toyota RAV4 review

Pros

  • Lots of space and practical touches
  • Good equipment levels
  • Cheap to run

Cons

  • Interior looks a bit cheap
  • Can be expensive

Sporty SEAT brings sharp styling and green creds

Sharing its tech with the VW Golf, the SEAT Leon is a more cost-effective alternative from the VW family. Producing a mere 27g/km, the Leon hybrid is as environmentally friendly as it is family friendly.

With sharp styling and a great drive, it’s no surprise that the Leon is SEAT’s best-selling model in the UK. It’s sportiness will thrill some, though the cabin tech takes a bit of getting used to.

Price new: From £23,895
Price used: From £10,077

To find out more, read our full SEAT Leon review

Pros

  • Sensible pricing
  • Good tech and practicality
  • Gratifying to drive

Cons

  • Infotainment can be a bit fiddly
  • FR versions have a firm ride

Effortless low-emission luxury

While sportier variants of the Mercedes-Benz C-Class will be emitting levels of CO2 way above 100g/km, the two plug-in hybrid versions – namely the C300e and the 300de – keep the emissions below 40g/km.

Aside from firmer suspension, which will put some off, the C300de is a quiet, understated gem. It features a swathe of easy-to-use tech and no one can mistake the quintessentially effortless style of a Mercedes.

Price new: From £45,175
Price used: From £24,352

To find out more, read our full Mercedes-Benz C-Class review

Pros

  • Excellent interior
  • Modern technology
  • Efficient engine options

Cons

  • Some areas of low quality
  • Not that spacious

Distinctive Niro proves a winner in the low-emission stakes

Like the IONIQ family, the Niro is offered in hybrid, plug-in hybrid and fully electric variants. Though opting for the all-electric Kia e-Niro is the greenest decision of this compact SUV, the hybrid Niro has claimed CO2 emissions of 36g/km.

With a distinct look and spacious interior, the Niro makes an excellent choice for bigger families and the seven-year Kia warranty is a cherry-topping perk.

Price new: From £21,074
Price used: From £19,424

To find out more, read our full Kia Niro review

Pros

  • Economical hybrid option
  • Excellent warranty
  • Practical and neatly finished

Cons

  • Not that fun to drive
  • Choppy ride

A low-emission family contender 

Though recent price increases mean the Octavia can be no longer labelled ‘cheap’, the Octavia is the best pound for pound family car.

There’s loads of room and a massive boot and since the ride is smooth and refined, it ticks a lot of boxes. Though the hybrid isn’t at its best on longer journeys, the electrified version has a CO2 output of 36g/km. If you’re not too bothered by a bit of body roll, this VW-family hatchback is a well-priced contender.

Price new: From £25,965
Price used: From £10,670

To find out more, read our full Skoda Octavia review

Pros

  • Lots of interior space
  • Vast boot
  • Wide array of options

Cons

  • Hybrid's best for short trips
  • Not rewarding for keener drivers

A brilliant bestseller with space, style and low emissions

The best-selling car Toyota has in the UK, the Yaris has a great reputation for fuel economy. This 1.5-litre hybridised petrol engine is the only one available, offering an impressive 68.9mpg and keeping official emissions figures below 100g/km.

It’s stylish, with great kerb appeal and roominess enough, especially for front passengers. While the boot is a bit small and the interior dates quicker than others, it’s a fine choice for environmental and fuel cost savings.

Price new: From £22,630
Price used: From £10,924

To find out more, read our full Toyota Yaris review

Pros

  • Cheap to run
  • Lots of equipment
  • Affordable to buy

Cons

  • Competitors are better to drive
  • Interior is a bit dull

A fine-driving SUV that offers luxury and low emissions

It was tough to decide whether the award-winning BMW 330e had more need to be on this list over the X5, but for all the SUV drivers reading this, this one is for you.

The plug-in hybrid variant of the X5 not only boasts a mere 39g/km (or 41, if you opt for the M Sport), but you could also see a fuel economy of around 135mpg. This is due to the 60 miles of pure electric charge and on condition you regularly plug-in to use the battery. Nonetheless, the X5 xDrive45e stats are impressive.

Price new: From £70,095
Price used: From £29,048

To find out more, read our full BMW X5 review

Pros

  • Upmarket interior
  • Great to drive
  • Economical engine options

Cons

  • Rear room isn't great
  • Fiddly media and climate controls

Pricey but poised performance hybrid

Contrary to historical records, Porsche’s green credentials are getting stronger and stronger. With the launch of the much-lauded all-electric Porsche Taycan, the used market for Porsche hybrids may offer some gems.

While mpg ratings won’t be kind to wallets, the Panamera boasts a remarkable 57g/km. Achieving that means keeping the battery of this family-friendly sports car topped up, but could be worth the effort for keen drivers.

Price new: From £81,120
Price used: From £28,178

To find out more, read our full Porsche Panamera review

Pros

  • Superb driving experience
  • Advanced technology
  • Comfortable and refined

Cons

  • Not as spacious as conventional saloons
  • Very big

The well-built Korean hybrid with top tech

The Ioniq was one of the first cars to come with every variant of powertrain; petrol, diesel, electric, hybrid, plug-in hybrid.

Yet, even the hybridised Ioniq variants offer great scores on the emissions front. The plug-in hybrid states only 26g/km, with 39 miles of pure electric driving. Alternatively, the hybrid without the faff offers 84g/km, with a claimed fuel economy of over 75mpg. 

Price new: From £21,695
Price used: From £8294

To find out more, read our full Hyundai Ioniq review

Pros

  • Good warranty cover
  • Economical and cheap to run
  • Competitive pricing

Cons

  • Interior isn't the most appealing
  • Toyota's Prius is more efficient

First-time drivers’ favourite fuel and eco-friendly motor

Outclassing the Renault Clio on price and emissions (albeit by a cat’s whisker), the Fiesta is a popular model on UK roads.

‘ECOnetic technology’ and ‘EcoBoost’ are Ford’s watchwords for good fuel economy and respectable green credentials. With the 1.0-litre petrol engine emitting 108g/km, the 1.5-litre diesel engine fares a little better at 96g/km. Now in its eighth generation, the most recent Fiesta features great build quality and a swathe of kit, but it goes out of productiuon this year. 

Price new: From £19,350
Price used: From £4,361

To find out more, read our full Ford Fiesta review

Pros

  • Fun to drive
  • Well equipped
  • Compact yet practical

Cons

  • Cheap interior trims
  • Quite expensive

Which cars emit less than 75g/km of CO2?

Ultra-low emissions vehicles (ULEVs) are cars or vans with 75g/km or less carbon emissions. ULEVs meet Euro 6 standards and have a 20-mile zero-emission range (minimum). Simply ‘low-emission vehicles’ are those with emissions less than 100g/km.

When deciding on the vehicle with the lowest carbon footprint, some calculate the ‘well-to-wheel’ emissions as part of the overall calculation. This includes the emissions during production. Many manufacturers have integrated high levels of recycled materials, solar power and other earth-conscious solutions into the making of their motors. 

Most consumers, however, are simply interested in the carbon emitted while driving. Hybridised vehicles make the best compromise between pure electric and pure conventionally fuelled cars regarding the change to driver habits. What’s more, the partial electrification of a fossil-fuelled car improves the fuel economy and lowers the CO2g/km emissions.

Does a hybrid car make sense?

Hybrid cars have been squeezed out of the exemptions list in the most recent update to the ULEZ criteria, so your best bet is to buy electric for ultimate ‘zero emissions’. And since the used electric car market is already beginning to grow, this option isn’t as limiting as it once was. But when it comes to determining which car has the best emissions, the question remains; what are you using it for?

For example, if you tow a caravan or trailer, options to go electric are fewer. Since we’ve already got a few lists of the best electric vehicles; for range, for families, SUVs, small EVs and affordable electric cars, this list looks at vehicles beyond the obvious all-electric choices.