BMW 3-series – MPG and running costs

Assuming you have access to a charger and don’t spend your days doing lengthy journeys, the plug-in hybrid 330e should offer the lowest running costs of the 3-series range. Official economy figures of up to 188.3mpg can be taken with a pinch of salt, but with an all-electric range of up to 35 miles, most commutes could be tackled on battery power alone. Combine this with a low BiK rate for company car drivers and the 330e looks like a very attractive proposition. 

The pure-combustion 320i posts good economy figures with a quoted 43.5mpg, with the 2-litre diesel 320d rising to 57.6mpg. Despite the demonisation of diesel there’s no getting away from the fact that the 3-series models wearing a ‘d’ badge are by far and away the most economical of the pure-combustion models – even the 335bhp M340d achieves a quoted 46.3mpg despite its less efficient xDrive all-wheel drive system and 3-litre displacement. As these are WLTP figures they should be achievable when on a gentle cruise, but if you use the performance to its full then expect to drop into the 20s.

The least economical of the range is the petrol-powered M340i xDrive, with its 369bhp 3-litre straight-six achieving a 35mpg WLTP figure. Surprisingly, this figure isn't too hard to reach on a long run thanks to its 48V hybrid tech, although a hard drive will see economy drop to the low teens. 

With extended service intervals running a 3-series shouldn’t break the bank and BMW offers a pay monthly servicing option at £25 per month for 36 months. Given this only covers two services and the car’s first MoT it’s perhaps best avoided unless you really want to fix your motoring costs.