This page collects every fuel-economy figure the EPA publishes for the 2025 Audi A8 quattro. Below you will find the headline combined, city, and highway MPG, the estimated annual fuel cost at three different driving levels, the tailpipe CO₂ emissions, and a full breakdown of the engine and drivetrain. If you want to know whether this generation got more or less efficient over the years, the year-over-year table further down covers every model year the EPA has rated.

Key takeaways

  • Returns 63% worse combined MPG than the average car in the Large Cars class for the 2025 model year (59.5 MPG class average).
  • The most efficient car in the Large Cars class for the 2025 model year is the Lucid Air Pure RWD with 19 inch wheels at 146 MPG.
  • EPA estimates this car costs around $5,000 more in fuel over five years than an average new vehicle of the same model year.
  • Requires premium gasoline, which typically adds about 40 to 60 cents per gallon to the EPA's annual fuel cost estimate.

Fuel economy at a glance

These are the EPA's official ratings for the 2025 Audi A8 quattro. The numbers come from a standardised laboratory test cycle and are the same figures that appear on the window sticker of every new car. Real-world mileage varies with driving style, weather, fuel quality, and how heavily loaded the car is.

Combined MPG is a 55/45 weighted blend of the city and highway test cycles. The EPA uses it as the single number you can compare across the entire dataset, including hybrids and EVs (which use the equivalent MPGe figure).

Combined MPG 22 MPG
City MPG 20 MPG
Highway MPG 26 MPG
Annual fuel cost $3,150
Tailpipe CO₂ 414 g/mi
Fuel type Premium

How the 2025 Audi A8 quattro compares

The 2025 Audi A8 quattro returns 22 combined MPG. Cars in the Large Cars class for the same model year average 59.5 MPG, which puts this car behind the class average by about 63%.

The most efficient car in the Large Cars class for the 2025 model year is the Lucid Air Pure RWD with 19 inch wheels at 146 MPG. The bar chart below puts the Audi A8 quattro alongside the class best and the class average so you can see the full picture.

For broader context, the average new car of the 2025 model year (across all classes) returns 44.3 MPG. Larger vehicles pull the all-cars average down, so do not use that figure on its own to judge a small car or a hybrid. The full list of the most efficient cars of the 2025 model year is on its own page.

2025 Audi A8 quattro
22 MPG
Class average, 2025
59.5 MPG
Class best, 2025
146 MPG
Average new car, 2025
44.3 MPG

Annual fuel cost across driving patterns

The headline annual fuel cost the EPA publishes assumes 15,000 miles of driving per year and a fuel mix of 55% city and 45% highway. The dollar figure is calculated using the EPA's current reference price for premium gasoline, which is $4.61/gallon. EPA updates that reference periodically rather than tracking live pump prices, so treat it as a window-sticker estimate rather than today's pump number.

The table below scales the EPA's number to three common driving patterns. The combined MPG and the reference fuel price stay constant, only the annual mileage changes. To get a current-prices estimate, take your local gas price and multiply by 681.8 gallons (the car's annual consumption at the rated MPG).

Driving pattern Estimated annual fuel cost
Light driver, 7,500 miles per year $1,575
Average driver, 15,000 miles per year $3,150
Heavy driver, 25,000 miles per year $5,250

Year-over-year MPG for the Audi A8 quattro

The EPA has rated the Audi A8 quattro across 7 model years, from 1999 Audi A8 quattro through 2026 Audi A8 quattro. The numbers below are the best combined MPG figure the EPA published for each year, which lets you see when the car was at its most efficient and how recent generations stack up.

Combined MPG has stayed in roughly the same range across the run. The peak rating came with the 2024 Audi A8 quattro at 22 MPG.

Year Combined MPG Open year page
2026 22 MPG 2026 Audi A8 quattro
2025 22 MPG this page
2024 22 MPG 2024 Audi A8 quattro
2002 18 MPG 2002 Audi A8 quattro
2001 18 MPG 2001 Audi A8 quattro
2000 18 MPG 2000 Audi A8 quattro
1999 18 MPG 1999 Audi A8 quattro

Compare against other Large Cars for 2025

If you are cross-shopping the 2025 Audi A8 quattro, the most useful comparison is against the other cars in the Large Cars class for the same model year. The list below shows the highest-MPG peers, ranked from most to least efficient. Click any of them to open its full page.

The Lucid Air Pure RWD with 19 inch wheels leads this group at 146 MPG, 124 MPG ahead of the 2025 Audi A8 quattro.

Specifications

The 2025 Audi A8 quattro runs a 3-liter 6-cylinder turbocharged engine paired with a automatic (s8), sending power through all-wheel drive.

Engine, transmission, and drivetrain together drive most of the variation in fuel economy across trims. A larger engine moves the car with less effort but burns more fuel. A turbo lets a small engine punch above its weight, often without much MPG penalty. All-wheel drive adds traction and weight, and usually costs a couple of MPG compared with two-wheel drive of the same engine.

Vehicle class
Large Cars
Engine
3L 6-cylinder turbocharged
Transmission
Automatic (S8)
Drivetrain
All-Wheel Drive
Fuel type
Premium
Annual petroleum use
13.5 barrels per year
Start-stop system
Yes

Common questions about the 2025 Audi A8 quattro

Quick answers to the questions people most often search for when looking up the 2025 Audi A8 quattro.

  • Is the 2025 Audi A8 quattro fuel efficient?
    Not particularly. The 2025 Audi A8 quattro returns 22 combined MPG, which trails the average car in the Large Cars class for the same model year by about 63%.
  • What MPG does the 2025 Audi A8 quattro get?
    The EPA rates the 2025 Audi A8 quattro at 22 combined MPG, 20 MPG in city driving, and 26 MPG on the highway. Real-world numbers depend on your driving style, the weather, and how loaded the car is.
  • How much does it cost to fuel a 2025 Audi A8 quattro per year?
    The EPA estimates an annual fuel cost of $3,150 for the 2025 Audi A8 quattro. That figure assumes 15,000 miles of driving per year, a 55% city and 45% highway split, and the EPA's published average fuel price for the rated fuel grade.
  • Does the 2025 Audi A8 quattro require premium gas?
    Yes. The EPA lists the 2025 Audi A8 quattro as requiring premium gasoline. Running it on regular can reduce performance and may affect engine warranties, so it is not a recommended way to save at the pump.
  • Has the Audi A8 quattro become more fuel efficient over time?
    Combined MPG has stayed close to flat across the run. Both the earliest (1999 Audi A8 quattro, 18 MPG) and most recent (2026 Audi A8 quattro, 22 MPG) versions sit in the same range.
  • How much CO₂ does the 2025 Audi A8 quattro emit?
    Tailpipe CO₂ emissions are 414 g/mi. Multiplied across a typical year of driving (15,000 miles) that works out to about 6,210 kilograms of CO₂.
  • What is the difference between the city and highway MPG of the 2025 Audi A8 quattro?
    City driving returns 20 MPG and highway driving returns 26 MPG, a gap of 6 MPG. A spread that wide is typical of cars with conventional automatic or manual transmissions, where stop-start city traffic eats more fuel than a steady highway cruise.
  • What engine is in the 2025 Audi A8 quattro?
    The 2025 Audi A8 quattro has a 3-liter 6-cylinder turbocharged engine (EPA description: SIDI; Mild Hybrid).
  • What transmission and drivetrain does the 2025 Audi A8 quattro have?
    The 2025 Audi A8 quattro comes with a automatic (s8) transmission and all-wheel drive. All-wheel-drive variants typically read 1 to 3 MPG lower than the front-wheel-drive equivalent of the same engine, since the extra hardware adds weight and parasitic loss.
  • How does the 2025 Audi A8 quattro compare to the best car in its class?
    The most efficient car in the Large Cars class for the 2025 model year is the Lucid Air Pure RWD with 19 inch wheels at 146 combined MPG. The Audi A8 quattro returns 22 MPG, a gap of 124 MPG. If you are comparing on fuel economy alone, the class leader is worth a look.

Source: U.S. EPA fuel economy dataset. Annual fuel cost figures assume 15,000 miles of driving per year and a 55% city, 45% highway split. Real-world mileage varies with driving conditions, vehicle maintenance, fuel quality, and driver behaviour.