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. The plug-in hybrid gets a much bigger battery than most of its rivals, giving it around double the EV range and making it ideal for company-car drivers. 

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 up to 61.4mpg depending on trim level and wheels, with CO2 emissions of 120-127g/km. This compares with 60.1mpg for the BMW 320d M Sport.

Sitting above it, there's the C 300 d, which is also a four-cylinder 2.0-litre turbodiesel with similar running costs to the more affordable version; despite the extra power it can still achieve 55mpg.

The petrol range kicks off with the C 200, which uses a 1.5-litre turbocharged four-cylinder engine. Like the diesels, the C 200 and the now-withdrawn C 180 petrol return similar efficiency to each other and can manage up to 44mpg, with emissions figures from 141-163g/km.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.

Finally, there’s the high-performance C 43 with its turbocharged 2.0-litre four cylinder. The previous-generation C 43 used a larger six-cylinder unit and while this new, smaller engine may not be as characterful, it should, in theory, be more economical. Mercedes claims it can return up to 34mpg, however to achieve this, you will have to resist the urge to use the car’s 402bhp performance too often.

The big news for the plug-in hybrid C 300 e is 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, and giving it a serious range advantage over rivals. CO2 emissions as low as 14g/km and up to 470mpg should also make it the cheapest version to run for business users, thanks to a lower BiK liability. As with any plug-in hybrid, the C 300 e is most efficient if you regularly drive on battery power and recharge as often as possible. Even on a longer drive we got almost 70mpg out of it.

Insurance groups

Insurance groups seem to be slightly higher than those for the previous model. A C 200 petrol in the entry-level trim starts in group 38 out of 50, while the C 300 AMG Line is two groups higher. Diesel versions span almost identical groups, while the C 300 e plug-in hybrid is in group 45 and the C43 is in the highest band of 50. 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
    C200 Sport 4dr 9G-Tronic
  • Gearbox type
    Semi-auto
  • Price
    £37,780

Most Economical

  • Name
    C300e AMG Line 4dr 9G-Tronic
  • Gearbox type
    Semi-auto
  • Price
    £44,100

Fastest

  • Name
    C300d AMG Line 4dr 9G-Tronic
  • Gearbox type
    Semi-auto
  • Price
    £44,920

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