Mercedes B-Class (2011-2018) review - MPG, CO2 and Running Costs

With family use in mind, the B-Class has been tuned for frugality, no matter which engine you choose

We could just wipe this debate out right here and say buy the Electric Drive B-Class – you’ll pay somewhere in the region of £2 for every 100-miles you drive (an utterly unbeatable cost-per-mile ratio compared to petrol or diesel) and you’ll never have to pay any road tax. Of course, there’s a catch and it’s the Electric Drive’s limited 124-mile range, so it won’t be suitable for all. 

While there are no current B-Class models that dip into the sub-100g/km free road tax bracket, all of the diesel models are in Band B, so will cost you just £20 a year to tax, with the exception of the B220 CDI 4MATIC four-wheel-drive model, which has 130g/km CO2 emissions so costs £110 to tax for a year.

While fuel economy claims should always be taken with a pinch of salt, both the B180 CDI and B200 CDI say they can beat 70mpg when fitted with Merc’s 7G-TRONIC automatic gearbox, and experience tells us they’re not fibbing – at least 60mpg is possible with a diesel B-Class in daily driving.

The petrol models fare unsurprisingly less well, but they’re not entirely outclassed. Both B180 and B200 claim better than 50mpg on average (mid-forties is probably about right) and given that they save you a considerable amount of cash at purchase time compared to a diesel, they can readily absorb the extra costs of tax and fuel.

Insurance groups

The lowest rated model is a B180 CDI SE which sits in Group 12 for insurance, while a a B220 CDI 4MATIC sits in Group 27. Electric Drive models sit in Groups 24 and 25.

Depreciation

While you might expect any car with a Mercedes badge to hold back the hordes of depreciation, it’s not quite the case – the B-Class doesn’t beat the benchmark 50 per cent retained value after three years (a £22k B180 will be worth roughly £9k after three years) so it’s no better off than its more mass-market rivals. It’s also a car with a long, sometimes bewildering options list so choose your spec carefully to avoid paying for toys that won’t add value come resale time.

Which Is Best

Cheapest

  • Name
    B180 Sport 5dr Auto
  • Gearbox type
    Semi-auto
  • Price
    £26,645

Most Economical

  • Name
    B250e AMG Line Executive 5dr Auto
  • Gearbox type
    Semi-auto
  • Price
    £34,485

Fastest

  • Name
    B250 AMG Line Executive 5dr Auto
  • Gearbox type
    Semi-auto
  • Price
    £32,695

Most Popular

Energy firms want the right to switch off electric cars charging at home
Electric cars

Energy firms want the right to switch off electric cars charging at home

New powers being sought to allow energy providers to turn off high-drain devices to manage electricity network
18 Sep 2020
Audi A3 vs Mercedes A-Class
Car group tests

Audi A3 vs Mercedes A-Class

The Audi A3 and Mercedes A-Class are strong competitors in the premium hatchback market - we find out which is best
19 Sep 2020
New Rolls-Royce Ghost 2020 review
Rolls-Royce Ghost

New Rolls-Royce Ghost 2020 review

The all-new luxury Rolls-Royce Ghost saloon brings new levels of refinement
18 Sep 2020