In-depth Reviews

Mercedes CLA saloon - MPG, running costs & CO2

Petrol and diesel engines provide impressive fuel economy, and the hybrid version promises plenty of electric range

Carbuyer Rating

3.9 out of 5

MPG, running costs & CO2 Rating

3.5 out of 5

The Mercedes CLA is available with a range of petrol engines and one diesel engine, all borrowed from the Mercedes A-Class hatchback. While not quite class-leading, less powerful engines should prove cheap to run, with the CLA's most economy-focused driving mode and standard automatic gearboxes squeezing the most out of the fuel in the tank.

The CLA also has the lowest aerodynamic drag of any small saloon, helping it cut through the air and save fuel, especially on the motorway.

Mercedes CLA MPG & CO2

CLA 180 and 200 models are fitted with the same downsized 1.3-litre petrol turbo engine, albeit with different power outputs. Both can return up to 46.3mpg with the most economical trim and alloy wheel combination. CO2 emissions of 138g/km put them both in an appealing Benefit-in-Kind (BiK) band for company-car drivers.

Step up to the CLA 250 petrol, and the engine jumps in size to 2.0-litres, with a hit in fuel-efficiency as a result. However, 41.5mpg isn't too bad given the performance on offer. CO2 emissions stand at 154g/km for the 250, so it’s a bit more expensive for business users.

Company-car drivers will be served well by the CLA 250 e plug-in hybrid. It’s rather more expensive than a CLA 180 or 200 in an equivalent spec, but business users will appreciate a very low 6% BiK rate for 2020/21. We can see the appeal of the PHEV to private buyers too; the 44-mile electric range is very impressive, and it means that several days of commuting could be completed without using a drop of fuel.

The two AMG versions are purely focused on performance so, as you might expect, fuel economy takes a back seat. You can expect up to 36.2mpg for the 302bhp CLA 35, and around 31mpg from the full-fat performance CLA 45 S.

Every Mercedes CLA costs £150 a year in road tax, but spending over £40,000 (which is certainly possible if you splash out on options) incurs a £325 tariff in the first five renewal years, increasing the bill to £475.

Insurance groups

Insurance groups for the CLA range from group 27 for the CLA 180 to 35 for the CLA 250. The diesel sits in group 34 and the AMG CLA 35 occupies 42-43, while the CLA 45 S sits in 44-45. Groups for the plug-in hybrid are yet to be finalised.


Mercedes models come with a three-year/unlimited-mileage warranty, with three years of roadside assistance for added peace of mind. This matches the cover from BMW, while Audi limits mileage to 60,000. Hyundai throws in an extra two years of cover.


If you are looking to spread the cost of routine maintenance, Mercedes offers 'ServiceCare', with regular monthly payments that cover servicing for the first few years.

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