In-depth reviews

Mercedes GLC review - MPG, CO2 and running costs

Standard nine-speed automatic gearbox keeps running costs down and on-par with rivals

As a mid-sized SUV, it shouldn’t come as much of a surprise that the GLC can’t quite match the fuel economy of the C-Class saloon.

Still, the engine improvements introduced for 2019 resulted in small improvements across the board. The latest GLC 220 d delivers between 46.3mpg and 47.9mpg on the WLTP combined cycle, dependent on chosen optional equipment.

The GLC 300 d is slightly thirstier, offering 42.2mpg to 42.8mpg. In terms of carbon dioxide emissions, the GLC 220 d manages 156g/km, while the 300 d achieves 176g/km. Both cars see a slight increase in emissions when larger wheels are fitted.

Plug-in hybrid tech gives the GLC 300 de a 27-mile all-electric range and CO2 emissions from 48g/km, while Mercedes claims maximum fuel consumption on the combined cycle of 156.9mpg - although you'll have to ensure the battery is kept topped-up. 

The petrol GLC 300 returns up to 34.5mpg and has emissions from 187g/km. At the other end of the scale, the AMG GLC 63 S emits 294g/km and returns up to 21.7 mpg, while the GLC 43 manages 233g/km and up to 27.4 mpg.

Servicing and maintenance costs should be on a par with a BMW and Audi, and the fact it shares a number of parts with the C-Class saloon should bring down costs in the long term.

Insurance groups

The insurance groups for the GLC generally range from around group 28 to group 38 for the standard models, depending on engine and trim level. The AMG GLC 43 has a group 40 insurance rating, while the AMG 63 models tops out in group 47. Insuring a premium car such as this could be a big chunk of your annual running costs, and when we tested the previous-gen GLC 250 d AMG Line against a Volvo XC60 D4 R-Design and Audi Q5 2.0 TDI S line, the GLC was the most expensive to insure: our sample driver was quoted at around £1,200, compared to around £850 for the Volvo and Audi.


Premium SUVs are a popular part of the market, and the GLC has reasonable residual values to reflect this. The conventional range sits in the ballpark of around 45%, which is in line with rivals. The GLC Coupe is a stronger performer in the used market, keeping around 50% of its original value over the same period. The AMG models do not hold up so well in percentage terms and, due to their high list prices, will lose the first owner a considerable chunk of money.

Most Popular

How to transfer a number plate from one car to another
MINI number plate change
Tips & advice

How to transfer a number plate from one car to another

Need to know how to transfer a number plate between vehicles? Our step-by-step guide breaks it down
22 Nov 2020
Best mini jump starter packs 2020
Best jumper starter packs header
Product group tests

Best mini jump starter packs 2020

Don’t get caught out with a dodgy battery as we test eight of the best jump starter packs
18 Nov 2020
New Volkswagen Golf GTE 2020 review
Volkswagen Golf GTE

New Volkswagen Golf GTE 2020 review

Is the new 242bhp plug-in hybrid Volkswagen Golf GTE the pick of the range? We find out...
19 Nov 2020