Parkers overall rating: 4.7 out of 5 4.7

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

Petrol engines 2.7 - 3.7 mpp
Low figures relate to the least economical version; high to the most economical. Based on WLTP combined fuel economy for versions of this car made since September 2017 only, and typical current fuel or electricity costs.

Fuel economy

Petrol engines 20.6 - 27.4 mpg
  • Lower fuel economy than Coupe
  • Costly consumables and servicing
  • Not worth skimping on maintenance

Unlikely to be a huge concern on a six figure car such as this but running costs are worth considering if you plan to use this car daily – which you could do quite comfortably.

Whether you pick the 991 S or 4S the fuel economy is a promised 26.4-28mpg – not exactly stellar but certainly not unreasonable considering the performance available.

Consumables are going to be costly – tyres for those huge wheels and brake components will eventually wear out.

The service intervals (every 20,000 miles) are usefully spread out, but you should take into account the fact that proper Porsche maintenance isn’t cheap.

Luckily Porsche 911 models hold their value well, but skimping on any of the above will undoubtedly cost you in the long run – anyone buying your car will want to see that it has been meticulously cared for.

Let’s look at the positives here – the 911 Cabriolet produces only marginally more CO2 than the Coupe, with a promised 208g/km emitted from its high-performance engine.

Obviously that’s not a small number but it’s less than previous generations of 911, which featured larger naturally aspirated motors that produced more CO2 in test conditions. This car also features a gasoline particulate filter to help trap emissions too.

Only time will reveal the benefits of a smaller turbocharged engine when it comes to pollution – but for now the 911 Cabriolet is considerably greener than the 5.2-litre V10 in an Audi R8, for example.

Given its relatively new design it will be some time before we can talk definitively about how reliable the Porsche 911 Cabriolet is.

That said, the car feels fantastically well engineered and uses parts engineered by the enormous Volkswagen Group, so we reckon you won’t have many problems.

Ongoing running costs

Road tax (12 months) £520
Insurance group 50
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