Mercedes B-Class mini MPV (2012-2014) - MPG, running costs & CO2

Diesel engines offer excellent fuel economy

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MPG, running costs & CO2 Rating

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Mercedes B-Class MPG and CO2

There are three diesel models and two petrols to choose from when buying a B-Class and the diesels are the more efficient. The 1.5-litre in the B180 CDI returns 68.9mpg with CO2 emissions of 104g/km for tax of £20 a year, while the B200 CDI with the more powerful 2.1-litre engine matches that mpg figure while emitting 109g/km of CO2 for the same tax rate.

In the B220 CDI, the 2.1-litre diesel has been tweaked for more power, but economy is similar, at 67.3mpg with CO2 emissions of 108g/km. The B220 is only available with Mercedes’ 7G seven-speed automatic gearbox, which helps efficiency. This transmission is available as an option on other models and in all cases it matches or betters the fuel-economy figures of the same version with the six-speed manual gearbox.

Though the petrols can’t match the figures of the diesels, both the 1.6-litre B180 and B200 return 50.4mpg economy. They emit 129 and 130g/km of CO2 respectively, so road tax is £110 a year. These are pretty respectable figures.

It’s also worth bearing in mind that specifying larger alloy wheels reduces efficiency slightly, and although the difference is only a few grams of CO2 per kilometre, it’s enough to bump the car into a higher tax bracket in some cases.

Mercedes offers an all-electric version of the B-Class, the B250e, which emits no CO2 and is thus completely exempt from road tax and the London Congestion Charge.

Insurance groups

The entry-level diesel B-Class, the B180, falls into insurance group 15, while the entry-level petrol B180 is in group 19, along with the more powerful B200 CDI diesel. The B200 petrol is in group 23, while the B220 diesel is in group 24.


Mercedes offers fixed-price service plans across its range, starting from £24 a month – that’s for two services over two years. Service intervals are every 15,500 miles or once a year, whichever comes up first.


All Mercedes cars come with a three-year/unlimited-mileage warranty, which is good news for owners that do plenty of miles, as many three-year warranties are limited to 60,000 miles.

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