BMW 1 Series - MPG, CO2 and running costs
Both the 120 and M135 versions of the 1 Series come with class-leading efficiency, but there’s no PHEV option
In base 120 Sport form, the BMW 1 Series is 60kg heavier than the Mercedes A 180 Sport and yet it beats the Mercedes on efficiency thanks to its new frugal mild-hybrid engine. A figure of 53.3mpg (compared to the Mercedes’ 47.1mpg) is impressive, and it even trumps the Audi A3 in 35 TFSI configuration by 2.7mpg, despite the Audi weighing 100kg less. The Volkswagen Golf Style with a 1.5-litre MHEV powertrain is a fraction more economical at 53.4mpg, however. The BMW’s 121g/km emissions figure is a little better than the Mercedes’, but the same as the Audi’s.
The M135 is the thirstiest 1 Series given its focus on performance, but it shouldn’t ruin you at the pumps. The BMW’s 37.2mpg figure is better than you get from a Mercedes-AMG A 35 and the Audi S3, with both of those cars mustering 33.3mpg.
Neither the A3 nor the A-Class are available with four-wheel drive in their non-performance forms, unlike the 1 Series. With its larger 2.0-litre engine, and its four-wheel drive system adding additional weight, the 123 xDrive 1 Series isn't as economical as its front-wheel drive sibling, but 47.9mpg and emissions of 135g/km aren't bad, and certainly far better than you'll find if you go for an SUV - the typical sort of vehicle you'd expect to find four-wheel drive fitted to.
Used - available now
2021 BMW
1 Series
20,693 milesAutomaticPetrol1.5L
Cash £21,000
2020 BMW
1 Series
12,316 milesAutomaticPetrol1.5L
Cash £19,444
2017 BMW
1 Series
20,396 milesManualDiesel1.5L
Cash £12,416
2019 BMW
1 Series
46,328 milesAutomaticPetrol1.5L
Cash £14,883As there’s no diesel in the range, those who want even better economy numbers will be forced to look at the Mercedes A-Class, A3 or a Golf.
| Model | MPG | CO2 | Insurance group |
| BMW 120 Sport | 52.3mpg | 121g/km | 21 |
| BMW 123 xDrive M Sport | 47.9mpg | 135g/km | 26 |
| BMW M135 xDrive | 36.7mpg | 174g/km | 29 |
Tax
The M135 is the only version of the 1 Series to sit over the £40,000 mark, resulting in an additional surcharge on annual Vehicle Excise Duty (VED) costs for private buyers, applied from the second time the car is taxed up until it reaches six years old.
With emissions of 121g/km, the 120 sits in the same VED tax group as the Audi A3 and one lower than the Mercedes A-Class. Company car buyers will find the 120 in the 29 per cent Benefit-in-Kind (BiK) tax band, and the 123 xDrive in the 33 per cent bracket. The M135 fares much worse and languishes in the 37 per cent band. Those keeping an eye on their tax bill should consider the plug-in hybrid versions of either the A3, A-Class or Golf, or look to an all-electric alternative like the Volkswagen ID.3.
Insurance groups
Insurance on the BMW 1 Series is roughly what you’d find on similarly equipped Mercedes, Audis and Volkswagens, at group 21 for the 120. The M135 sits in group 29, two below the Audi S3 and eight lower than the Mercedes-AMG A 35.
Depreciation
The BMW 1 Series is expected to hold on to its resale value better than its Audi A3 and Mercedes A-Class competition, according to our expert data. The 1 Series, after three years or 36,000 miles, is likely to be worth between 50 to 56 per cent of its original value, whereas the A-Class will only be worth between 40 to 50 per cent over the same period. The A3 is on par with the 1 Series at 50 to 55 per cent, with the 35 TFSI Black Edition retaining the most value.
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