Parkers overall rating: 3.8 out of 5 3.8

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

Petrol engines 4.6 - 6.3 mpp
Diesel engines 6.4 - 7.6 mpp
Plug-in hybrid petrol engines 31.4 - 34.2 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.
Based on "Weighted" mpg; figures depend on the proportion of miles driven in pure electric mode and may vary widely

Fuel economy

Petrol engines 34.5 - 47.1 mpg
Diesel engines 51.4 - 61.4 mpg
Plug-in hybrid petrol engines 235.4 - 256.8 mpg
  • Impressive claimed fuel economy
  • Low CO2 emissions too
  • Should prove inexpensive to run

The B-Class boasts some impressive claimed fuel economy figures, and while the diesels are best on paper, we’ve found the petrol models can return some impressive mpg numbers too – easily matching the claimed figures.

Mercedes-Benz B-Class diesel mpg figures

The most economical B-Class is the B 180 d, returning 51.4-60.1mpg, depending on the size of the wheels and the spec of the car. These are the reasons figures can vary for one engine. The B 200 d returns 51.4-57.7mpg, while the B 220 d claims 50.4-56.5mpg.

Mercedes-Benz B-Class petrol mpg figures

On paper, the petrol engines in the B-Class can’t match the diesels for economy, and in many situations they can’t. The best performer is the B 180, claiming between 40.4mpg and 47.1mpg, while the more powerful version of the same engine (the B 200) offers 39.8-46.3mpg.

Move up the range to the B 220 4Matic and you can see 34.0-38.7mpg, while the more powerful B 250 performs better with 36.7-40.4mpg.

CO2 figures for the B-Class are pretty good for most of the range, especially with the diesels. The B 180 d emits just 112g/km – the lowest in the range – however the B 200 d and B 220 d aren’t far behind at 115g/km and 116g/km respectively.

The petrols are higher, with the B 180 producing 125g/km and the B 200 126g/km, while the B 250 emits 143g/km. The highest-emitter in the range is the all-wheel drive B 220 4Matic, at 153g/km.

  • Several recalls for previous B-Class
  • This car uses a lot of new tech
  • Covered by three-year warranty

The previous B-Class was the subject of several recalls, affecting things like the airbags, seats and door locks, but any of these issues should be ironed out for the current car.

This generation car does use a lot of new technology that debuted in the A-Class, so you might have to expect a couple of teething issues. However, if there are any problems then you can take it back to your local dealer under warranty, and if any recalls are issues then the car will be fixed free of charge.

Ongoing running costs

Road tax (12 months) £155 - £510
Insurance group 15 - 31
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