In-depth reviews

Mercedes C-Class saloon - MPG, running costs & CO2

Every C-Class is now electrified

Carbuyer Rating

4.3 out of 5

Owners Rating

3.0 out of 5

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MPG, running costs & CO2 Rating

4.0 out of 5

While the engine range still revolves predominantly around petrol and diesel engines, the latest C-Class is the first Mercedes to come with all its engines electrified. Every engine is fitted with either mild-hybrid or plug-in hybrid technology to boost efficiency.

Mild-hybrid models are fitted with a 48-volt system that harvests energy under deceleration into a small battery, and can provide a boost of up to 20bhp to take some strain off the engine, allowing for engine-off coasting and smoother restarts when the engine restarts.

Mercedes C-Class MPG & CO2

Despite the waning popularity of diesel engines, they're still a core element in the C-Class range. So far we've tested the C 220 d, which is likely to account for a good proportion of C-Class sales. It's capable of returning between 50.4mpg and 57.6mpg depending on trim level and wheels, with CO2 emissions of 130-148g/km. This compares with 60.1mpg for the BMW 320d M Sport, and the C-Class' also has slightly higher emissions.

Sitting above it, there's the C 300 d, which is also a four-cylinder 2.0-litre turbodiesel with virtually identical running costs to the more affordable version. 

The petrol range kicks off with the C 180 and C 200, which both use a 1.5-litre turbocharged four-cylinder engine. Like the diesels, these return similar efficiency to each other and can manage up to 45mpg, with emissions figures from 141-163g/km. This makes them well-suited to private buyers but places them towards the top of the Benefit-in-Kind (BiK) bandings for company-car drivers.

With a larger 2.0-litre petrol engine, the C 300 is more powerful, and also a bit more costly to run. It manages between 35 and 42mpg depending on the trim, while emitting 150-180g/km of CO2.

A plug-in hybrid C 300 e is set to follow on with a much larger 25.4kWh battery than the 13.5kWh version found in its predecessor. This should see its EV range jump from around 34 miles to just over 60 miles, making it possible to complete longer zero-emissions journeys and charge less often. Low CO2 emissions should also make it the cheapest version to run for business users, thanks to a lower BiK liability.

Insurance groups

Insurance groups haven't been announced yet for the new C-Class but ratings aren’t likely to stray too far from the outgoing model. The latter was in group 34 out of 50 in C 220 d SE trim, while the C 300 d is likely to be in the 40s. The Mercedes isn't likely to be cheap to cover but its groupings are roughly comparable with rivals such as the 3 Series. 

Warranty

Mercedes models are offered with a three-year/unlimited-mileage warranty, which matches the BMW 3 Series. This is slightly more appealing for very high-mileage drivers than the Audi A4's warranty, which expires after three years or 60,000 miles. More mainstream manufacturers tend to offer longer warranties, including Genesis with its five-year care package and Toyota with a free warranty that can last for up to 10 years.

Servicing

Buyers are offered fixed-price servicing plans by Mercedes; you can either spread the cost of maintenance over regular monthly payments or pay one upfront fee. Expect to pay around £30 a month to cover servicing for two years.

Next Steps

Which Is Best?

Cheapest

  • Name
    C180 S 4dr
  • Gearbox type
    Manual
  • Price
    £28,035

Most Economical

  • Name
    C300e Sport Edition 4dr 9G-Tronic
  • Gearbox type
    Semi-auto
  • Price
    £40,074

Fastest

  • Name
    C300e Sport Edition 4dr 9G-Tronic
  • Gearbox type
    Semi-auto
  • Price
    £40,074

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