Parkers overall rating: 4.5 out of 5 4.5

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

Reliable fuel consumption data for comparison purposes is not available for this model.

Fuel economy

A more stringent standard for fuel economy (WLTP) was introduced from September 2017, and this model was not required to undergo that test. Its fuel economy measured under the previous test system was 30 - 58 mpg. However these figures are less likely to be achievable in real world driving and so should never be compared to another car's mpg which was measured under the newer, more realistic WLTP system.

Clever on-board technologies help cut CO2, raise mpg and bring down bills. These are lumped together by BMW under the name of EfficientDynamics. This includes auto stop-start, a system that cuts out the engine when the car is stationary, capturing energy that would otherwise be lost through braking along with electric (rather than hydraulic) power steering.

It means that the 1 Series Convertible can add lower running costs in the shape of cheaper road tax and increased mpg to the traditional high BMW residual values.

In the 18 months leading up to the launch of the 1 Series Convertible, BMW arguably did more to reduce CO2 across its range than any other manufacturer. This Convertible benefits from many of those initiatives, including EfficientDynamics – a system that includes a function to turn off the engine when it's not needed and save energy. The 118d diesel is the stand-out model in the range with CO2 emissions of just 129g/km and fuel economy of 58mpg.

The best petrol is the 118i with emissions of 149g/km and 45mpg. Even the high performance 135i sneaks in under the top tax bracket at 224g/km – 1g/km more and it would be classed as one of the most polluting cars on the road and taxed accordingly.

While the quality of the trim and fitting also suggested that the BMW 1 Series Convertible would be a reliable car, a number of issues affected it, as well as its Sports Hatch and Coupe cousins.

BMW 1 Series Convertible recalls

Reliability is a BMW hallmark, but nevertheless, the 1 Series Convertible was the subject of three recalls.

Earlier recalls were related to an issue with the brake servo and a suspension component, but in May 2018 a more serious electrical fault causing engines to cut out was announced.

As both petrol and diesel 1 Series Convertibles could be affected, it’s vital that you contact a BMW dealer to check the work to correct the problem has been carried out before you buy a used example.

Ongoing running costs

Road tax (12 months) £125 - £330
See tax rates for all versions
Insurance group 24 - 38
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