Audi A5 Cabriolet convertible (2009-2017) - MPG, running costs & CO2

The Audi A5 Cabirolet is available with efficient diesel engines

Carbuyer Rating

3.3 out of 5

MPG, running costs & CO2 Rating

3.3 out of 5

There’s a choice of two petrol and four diesel engines when buying an Audi A5 Cabriolet and every engine in the range offers good performance and reasonable fuel economy. The diesels are the most frugal, but the petrols don’t lag particularly far behind and Audi has done its best to maximise engine efficiency by fitting stop-start technology to all A5 Cabriolet models.

Audi’s status as a premium manufacturer means servicing and insurance costs are likely to be higher than if you owned one of the alternatives. However, the same goes for cars made by manufacturers such as BMW and Mercedes, which a lot of buyers will consider to be the other obvious options.

Audi A5 Cabriolet MPG and CO2

The most efficient engines are the diesels, with the 148bhp 2.0-litre TDI topping the class thanks to fuel economy of 57.6mpg and 129g/km of CO2 emissions. The A5 Cabriolet with this engine sits has an annual road tax bill of £110.

As you move up through the diesel line-up, the cars get increasingly quick and the mpg figures gradually slip down to the 44.1mpg quoted for the range-topping diesel model, the 3.0-litre TDI with quattro four-wheel drive and Audi’s seven-speed S tronic gearbox. Its CO2 emissions of 167g/km mean it costs £210 a year to tax.

The 187bhp version of the 2.0-litre TDI gives you the best of both worlds, with very punchy performance, a fuel economy figure of 55.4mpg and CO2 emissions of 133g/km for reasonable running costs.

The two petrol engines offer relatively good economy, even if the headline figures don’t quite match those of the diesels. The 175bhp 1.8-litre turbo petrol can do 45.6mpg with CO2 emissions of 144g/km, resulting in an annual tax bill of £145.

The more powerful 227bhp 2.0-litre turbo petrol engine is capable of 42.8mpg and costs £185 a year in road tax. Adding four-wheel drive makes fuel economy slightly worse and pushes the car into a higher tax band, so it’ll cost an extra £25 a year to tax.

Insurance group

A fairly wide choice of engines means the A5 Cabriolet falls into a similarly wide range of insurance groups. The 1.8-litre petrol model is rated as group 29, with the diesels predominantly slotting into groups 30 and 33. The powerful 3.0-litre diesel is in group 39.


Go for any of the 2.0-litre or smaller engines and an interim service at an Audi dealer will cost £159 – or £309 for a full service. The bigger, more powerful 3.0-litre diesel models are slightly more expensive, at £189 and £375 respectively. Audi also offers fixed-price three-year servicing cover, which you can pay for by monthly direct debit.


Audi offers a three-year/60,000-mile warranty to A5 Cabriolet buyers, which is similar to the three-year/unlimited-mileage warranty BMW offers on the 4 Series convertible.

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