2018 Audi A6 quattro: MPG and fuel economy
The 2018 Audi A6 quattro is rated by the U.S. Environmental Protection Agency at 26 combined MPG, with 22 MPG in the city and 31 MPG on the highway. That lands well below the average for cars in the Midsize Cars class in the same model year.
This page collects every fuel-economy figure the EPA publishes for the 2018 Audi A6 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. The EPA rates 2 separate variants of this car (different engine, transmission, or drivetrain combinations), and you can compare them side by side in the trims table. 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 20% worse combined MPG than the average car in the Midsize Cars class for the 2018 model year (32.6 MPG class average).
- The most efficient car in the Midsize Cars class for the 2018 model year is the Hyundai Ioniq Electric at 136 MPG.
- The Audi A6 quattro has gained 8 MPG since its first rated model year, the 1995 Audi A6 quattro at 18 MPG.
- EPA estimates this car costs around $2,500 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 2018 Audi A6 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.
When the EPA tests several variants of the same nameplate (for example, a front-wheel-drive version and an all-wheel-drive version), each gets its own rating. The figures shown here are the headline variant, taken as the configuration with the best combined MPG. The trims table further down covers all 2 variants side by side.
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 | 26 MPG |
| City MPG | 22 MPG |
| Highway MPG | 31 MPG |
| Annual fuel cost | $2,650 |
| Tailpipe CO₂ | 347 g/mi |
| Fuel type | Premium |
How the 2018 Audi A6 quattro compares
The 2018 Audi A6 quattro returns 26 combined MPG. Cars in the Midsize Cars class for the same model year average 32.6 MPG, which puts this car behind the class average by about 20%.
The most efficient car in the Midsize Cars class for the 2018 model year is the Hyundai Ioniq Electric at 136 MPG. The bar chart below puts the Audi A6 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 2018 model year (across all classes) returns 25.6 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 2018 model year is on its own page.
Trim variants rated for 2018
The EPA rates 2 separate variants of the 2018 Audi A6 quattro. The differences come from the engine size, transmission type, and drivetrain (front-wheel drive, all-wheel drive, and so on). The same nameplate can land several MPG apart depending on the configuration you actually buy.
| Engine and transmission | Drive | Combined | City | Highway | Annual cost |
|---|---|---|---|---|---|
| 2L, 4-cyl, turbo, Automatic (S8) | All-Wheel Drive | 26 MPG | 22 MPG | 31 MPG | $2,650 |
| 3L, 6-cyl, supercharged, Automatic (S8) | All-Wheel Drive | 23 MPG | 20 MPG | 29 MPG | $3,000 |
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 576.9 gallons (the car's annual consumption at the rated MPG).
| Driving pattern | Estimated annual fuel cost |
|---|---|
| Light driver, 7,500 miles per year | $1,325 |
| Average driver, 15,000 miles per year | $2,650 |
| Heavy driver, 25,000 miles per year | $4,417 |
Year-over-year MPG for the Audi A6 quattro
The EPA has rated the Audi A6 quattro across 31 model years, from 1995 Audi A6 quattro through 2025 Audi A6 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.
The 1995 Audi A6 quattro returned 18 MPG. The most recent 2025 Audi A6 quattro returns 26 MPG. That is an improvement of 8 MPG over 30 model years, the kind of gain that usually comes from smaller engines, hybrid systems, or aerodynamic redesigns.
Compare against other Midsize Cars for 2018
If you are cross-shopping the 2018 Audi A6 quattro, the most useful comparison is against the other cars in the Midsize 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 Hyundai Ioniq Electric leads this group at 136 MPG, 110 MPG ahead of the 2018 Audi A6 quattro.
Specifications
The 2018 Audi A6 quattro runs a 2-liter 4-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
- Midsize Cars
- Engine
- 2L 4-cylinder turbocharged
- Transmission
- Automatic (S8)
- Drivetrain
- All-Wheel Drive
- Fuel type
- Premium
- Annual petroleum use
- 11.4 barrels per year
- Start-stop system
- Yes
Common questions about the 2018 Audi A6 quattro
Quick answers to the questions people most often search for when looking up the 2018 Audi A6 quattro.
-
Is the 2018 Audi A6 quattro fuel efficient?
Not particularly. The 2018 Audi A6 quattro returns 26 combined MPG, which trails the average car in the Midsize Cars class for the same model year by about 20%. -
What MPG does the 2018 Audi A6 quattro get?
The EPA rates the 2018 Audi A6 quattro at 26 combined MPG, 22 MPG in city driving, and 31 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 2018 Audi A6 quattro per year?
The EPA estimates an annual fuel cost of $2,650 for the 2018 Audi A6 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 2018 Audi A6 quattro require premium gas?
Yes. The EPA lists the 2018 Audi A6 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 A6 quattro become more fuel efficient over time?
Yes. The first EPA-rated Audi A6 quattro, the 1995 Audi A6 quattro, returned 18 combined MPG. The most recent 2025 Audi A6 quattro returns 26 MPG, an improvement of 8 MPG over the run. -
How much CO₂ does the 2018 Audi A6 quattro emit?
Tailpipe CO₂ emissions are 347 g/mi. Multiplied across a typical year of driving (15,000 miles) that works out to about 5,205 kilograms of CO₂. -
What is the difference between the city and highway MPG of the 2018 Audi A6 quattro?
City driving returns 22 MPG and highway driving returns 31 MPG, a gap of 9 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 2018 Audi A6 quattro?
The 2018 Audi A6 quattro has a 2-liter 4-cylinder turbocharged engine (EPA description: SIDI). Smaller turbocharged engines like this one tend to deliver bigger-engine power on demand while keeping fuel economy closer to a non-turbo version of the same displacement. -
What transmission and drivetrain does the 2018 Audi A6 quattro have?
The 2018 Audi A6 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 2018 Audi A6 quattro compare to the best car in its class?
The most efficient car in the Midsize Cars class for the 2018 model year is the Hyundai Ioniq Electric at 136 combined MPG. The Audi A6 quattro returns 26 MPG, a gap of 110 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.