Parkers overall rating: 4.6 out of 5 4.6

Miles per pound (mpp) Miles per pound (mpp)

Petrol engines 3.3 - 5.5 mpp
Diesel engines 5.4 - 6.5 mpp
Low figures relate to the least economical version; high to the most economical. Based on WLTP combined fuel economy for versions of this car made since September 2017 only, and typical current fuel or electricity costs.

Fuel economy

Petrol engines 24.6 - 41.5 mpg
Diesel engines 44.1 - 52.3 mpg
  • Expensive servicing and maintenance costs
  • Fuel bills can be low with diesel engines
  • Running an AMG model will be very costly

Although its expensive to buy and dealership servicing isn’t known for being cheap, most running costs associated with the Mercedes-Benz C-Class Cabriolet are very reasonable, so long as you choose your engine carefully.

Under the latest emissions standards, the lowest CO2 is on offer in the diesel range – spanning 126g/km for the C 220 d on 18-inch wheels, to 151g/km for a C 300 d on 19-inch wheels.

Petrol C-Class Cabriolets start with 146g/km CO2 for the mild-hybrid C 200, falling into the same bracket as the 149g/km C 180 despite the extra power on offer. The C 200 4Matic on 19-inch wheels is the highest of the non-AMG models, producing 168g/km; the C 300 starts at 153g/km – impressively low, given the performance on offer.

There’s further good news with residual values expected to average out in the 50 percent region over three years and 30,000 miles.

No version of the Mercedes-Benz C-Class Cabriolet range has CO2 emissions that dip below the 100g/km threshold, but the 2.1.-litre C 220 d with manual gearbox gets closest at 116g/km.

At the opposite end of the scale a 236g/km CO2 output marks out the Mercedes-AMG C 63 S Cabriolet as the most polluting in the line-up; earlier models are rated at 208g/km.

C-Class Cabriolet reliability

  • Tried and tested platform and engines
  • Long history of building convertible cars
  • Feels like it’s engineered to last

The three-pointed star logo and ‘reliability’ have been synonymous for decades, so we’re not expecting the Mercedes-Benz C-Class Cabriolet to blot the firm’s copy book.

Not only have all the mechanical and electronic components seen service in other C-Classes, most of them filter across myriad different models in the range, too, with few reported maladies.

So what of the soft-top? Given Mercedes’ long, illustrious and continuous history of producing cabriolets, the C-Class’s fabric roof with steel, aluminium and magnesium framework is unlikely to prove troublesome, provided it’s operated properly.

Ongoing running costs

Road tax (12 months) £30 - £520
See tax rates for all versions
Insurance group 33 - 50
How much is it to insure?