Parkers overall rating: 4 out of 5 4.0

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

Petrol engines 3.2 - 4.1 mpp
Diesel engines 4.6 - 5.0 mpp
Hybrid petrol engines 3.7 - 4.0 mpp
Hybrid diesel engines 4.6 - 5.0 mpp
Plug-in hybrid petrol engines 15.1 - 20.9 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.
Based on "Weighted" mpg; figures depend on the proportion of miles driven in pure electric mode and may vary widely

Fuel economy

Petrol engines 24.1 - 31.0 mpg
Diesel engines 37.2 - 40.4 mpg
Hybrid petrol engines 27.7 - 29.7 mpg
Hybrid diesel engines 37.2 - 40.4 mpg
Plug-in hybrid petrol engines 113.0 - 156.9 mpg
  • Better economy and emissions this time
  • PHEV is the best performer here
  • Avoid the S8 if fuel costs are an issue

What are the running costs?

With list prices easily broaching six figures, A8 running costs are not exactly priority number one, but for those companies that run these cars on their fleet, it’s reassuring to note that they will be less expensive to run than the model they replaced. Going on the figures alone, the plug-in hybrid version is the one to have.

According to official figures, both the standard- and long-wheelbase models will get close to 100mpg thanks to a near 30 mile electric-only range. Ensure you hardly (if ever) use the petrol engine and obviously the fuel cost figure will be much lower.

All normal A8s benefit from electrification (although only in the form of mild hybridisation) which means there’s some battery assistance, but won’t run solely on it alone like the PHEV does. As a result both V6s have lower CO2 emissions than before, so they’re a step in the right direction.

View full Audi A8 and S8 specs

Servicing and warranty

There should be no unpleasant surprises when it comes to servicing and maintaining an A8, as it is a luxury product offered by a premium carmaker – it’s going to be expensive, and rightly so. A number of service packages are also available from main dealers.

Warranty is three years and 60,000 miles, which you can extend to four or five years at an additional cost. Compared with up-to 10 years offered by rivals, Audi’s warranty looks unimpressive.


  • Lots of tech and driver assistance systems
  • It’s all used elsewhere though, same for the engines
  • Owners’ reviews report good things about reliability

As a big and technologically advanced car there are a number of areas where the Audi A8 could prove unreliable but we don’t think you should have too much to worry about in this regard.

The engines and MMI infotainment screens are used elsewhere, and the A8 has been assembled with a high standard of quality and solidness.

Also unlike a lot of smaller Audis, which can be plagued with reliability issues as they fall into middle age, Audi A8 owners report few issues and seem a happy bunch.

Ongoing running costs

Road tax (12 months) £510 - £520
Insurance group 44 - 50
How much is it to insure?