Audi A5 Cabriolet - MPG, running costs & CO2

The Audi A5 Convertible boasts excellent economy, but its warranty isn’t the most generous

Carbuyer Rating

4.0 out of 5

MPG, running costs & CO2 Rating

4.0 out of 5

Audi knows that many owners of even distinctly upmarket cars like the A5 Cabriolet still need to keep an eye on running costs, and this is especially true of business users – an important market for this kind of car. As a result of this, improvements in fuel efficiency and emissions for the latest Audi A4 saloon have also been made on the A5.

Audi A5 Cabriolet MPG & CO2

There are no prizes for guessing that the 187bhp 2.0-litre '40 TDI' diesel engine is the most fuel-efficient engine in the A5 Cabriolet lineup, at a claimed 47.1mpg. CO2 emissions are 127g/km, resulting in a Benefit-in-Kind (BiK) rating of 32%, although opt for quattro four-wheel-drive and this changes to 44.1mpg, 142g/km of CO2 and a 36% BiK rating. It’s no slouch, with the same power as the entry-level 2.0-litre 40 TFSI petrol engine. 

The latter will be popular with lower-mileage drivers and manages a still-impressive 37.7mpg with either a manual or an S tronic automatic. CO2 emissions are 139g/km for S tronic and 138g/km for manual models. A more powerful 242bhp version of the 2.0-litre petrol engine is also available, badged 45 TFSI, although fuel economy here drops to 34.9mpg with CO2 emissions of 158g/km on the smallest wheels.

After the first year’s CO2-based road tax (generally included in the on-the-road price), all Audi A5 Cabriolets will cost £140 a year to tax. Those with a list price (including options) of more than £40,000 will attract an additional £310 surcharge in years two to six, bringing the annual bill to £450 during that time. Benefit-in-Kind tax for company-car users starts in the 31% bracket for the entry-level 2.0-litre petrol, with diesel beginning one percentage point higher.


Insurance groups start from 35 for the 2.0-litre TFSI petrol in SE trim, and climb to 41 if you choose the 3.0-litre diesel. The S5 Cabriolet is most expensive to insure in group 45, although Audi is currently not selling new versions. This compares to the BMW 420i SE convertible’s group 30 and the 440i’s group 36.


All Audi models require regular servicing, with the option of yearly servicing for motorists who cover fewer than 10,000 miles a year, or variable for higher-mileage motorists. On the latter scheme, oil changes will be no less frequent than every 19,000 miles. Your dealer will advise you as to the right service schedule for you and will be happy to arrange a service plan to help spread the cost of regular servicing.


All Audis come with a warranty for three years/60,000 miles, although you can extend this to a four-year/75,000-mile or five-year/90,000-mile policy at extra cost. We feel that Audi’s standard warranty offer is rather less than generous – Mercedes and BMW both have no mileage limit on their warranties and non-premium companies are often more generous – Hyundai offers a five-year/unlimited-mileage warranty with every new car, for example.

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