Used BMW 6-Series Convertible (2011 - 2018) Costs

Review by Tim Bowdler on
Last Updated: 27 Aug 2015
This is the second generation of the 6-Series from BMW and the standards have been raised on the premium cruiser. The Porsche 911 Cabriolet, Jaguar XK Convertible and the Mercedes-Benz SL got off lightly when the original 6-Series Convertible was launched, but now they have a battle on their hands if looks are anything to go by, and BMW means business with this new model.

3.5 out of 5

Running costs

Achieving an average of 35.8mpg is very impressive. You’ll need to keep the car in comfort or normal mode to achieve the optimum fuel return but flick the lever into Sport+ and you’ll soon be back at a filling station. BMW dealers can be expensive but service is usually first class.

* based on most recent data

Estimated fuel cost for 10,000 miles per year


£1,301 - £1,801 *


£991 - £1,032 *

The estimated fuel cost figure is a guide to how much this model will cost to fuel each year, so you can compare between cars. It's calculated by using the model's average mpg (calculated from both town centre and motorway driving) and the average fuel price. It's based on the following cost-per-litre: petrol 103p and diesel 109p. Prices are updated daily.

Summary Running Costs

Servicing period



Three years/unlimited mileage

Road tax (12 months)

£165.00 - £565.00

Vehicle excise duty (VED) varies according to the CO2 emissions and the fuel type of the vehicle. For cars registered after March 1st 2001 VED or road tax is based on the car's CO2 emissions. For cars registered before March 1st 2001 it is based on engine size.

Full running costs data

2.5 out of 5

Green credentials

  • A
  • B
  • C
  • D
  • E
  • F
  • G
  • H
  • I
  • J
  • K
  • L
  • M

CO2 emission figure (g/km)

Fuel economy rating

The arrows indicate the best and worst CO2 bands for this model.

Emissions summary

CO2 emissions are 185g/km for the 640i – that's road tax band I. However, buy the 650i and it emits a whopping 249g/km of CO2 – this places it in band L. To see the cost of annual tax as well as first-year showroom tax, visit the Parkers road tax calculator. The car features the Efficient Dynamics programme. These include Brake Energy Regeneration, lightweight engineering and Electric Power Steering.

On the 640i derivative things are taken a stage further with the implementation of start/stop and active aerodynamics behind the car’s kidney grille – the former being a technology that is unique in its segment.

Find the exact engine and CO2