In-depth Reviews

BMW 4 Series coupe - MPG, running costs & CO2

A wide spread of engines means the BMW 4 Series can return fuel economy figures that should suit most drivers

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MPG, running costs & CO2 Rating

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While many cars are cheaper to run than the BMW 4 Series, it’s impressively frugal when you consider the performance on offer and you should be able to achieve the figures quoted under the more realistic WLTP emissions test. Good residual values and fixed-priced servicing also help to keep running costs in check, although it goes without saying that servicing and maintenance will cost more than cars from a less upmarket brand.

BMW 4 Series MPG & CO2

If you’re focused on economy, you’ll want the the 420d, because it returns a respectable 49.6mpg, while CO2 emissions as low as 117g/km place it in the same Benefit-in-Kind (BiK) band as the 420i petrol for company-car drivers - a large proportion of 4 Series owners.

We reckon the 420d’s 0-62mph time of 7.4 seconds is plenty quick, but more powerful six-cylinder diesel options are also available in the form of the 430d and 435d (solely offered in M Sport trim). These automatic-only models return 42.8 and 40.4mpg respectively, and sit in the top BiK band.

If you don’t annually cover the roughly 12,000 miles necessary for a diesel to be really cost-effective, one of the petrols will suit you, and aren’t all as thirsty as their performance might suggest. Even the entry-level BMW 420i petrol is quick enough to hit 62mph from rest in 7.3 seconds, yet it can still return 38.2mpg. The BMW 430i is even quicker, but it costs a bit more to run as a result, while the powerful BMW 440i with its large six-cylinder petrol engine is likely to manage fuel-efficiency in the mid-30s if you drive gently.

After the first year's CO2-based road tax (generally included in the on-the-road price), all BMW 4 Series cost £145 a year to tax. Those with a list price (including options) of more than £40,000 are liable for an additional surcharge of £320 a year in years two to six, bringing the annual bill to £465 during that period. The size of the BMW’s alloy wheels affect its CO2 emissions, with larger and wider rims increasing the figure slightly. This is worth noting when you consider optional alloys.

Insurance group

With such a broad range of engines, the 4 Series falls into insurance groups ranging from 30 to 42. The 420d Sport is the cheapest to cover, while the 430d is in group 40. Top of the pile is the 435d xDrive M Sport.


All BMWs come with a three-year/unlimited-mileage warranty and breakdown recovery deal. There’s also a 12-year anti-corrosion warranty.


BMW offers fixed-price services that mean there should be no expensive surprises when it comes to your car’s maintenance.

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