18 MPG combined is what you can expect when you own a full-size, V8-powered luxury sedan. The 2021 Audi A8 L 4.0L isn’t built to sip fuel. It’s built for effortless power, supreme comfort, and understated elegance. Buyers likely prioritize a first-class experience, and fuel economy is secondary to the A8 L’s spaciousness, advanced technology, and smooth ride.

City and highway performance

The EPA estimates for the 2021 A8 L 4.0L show a big difference between city and highway driving. In the city, the V8 gets only 15 MPG because of stop-and-go traffic and frequent acceleration. But on the highway, the A8 L is a good cruiser, getting 23 MPG. This is thanks to the eight-speed automatic transmission and cylinder deactivation, which shuts down four cylinders under light load to save fuel.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2021 Audi A8 L 4.0L at $3,200. This is based on driving 15,000 miles per year, with about 55% in the city and 45% on the highway, using average fuel prices. $3,200 might seem like a lot compared to more fuel-efficient cars, but most A8 L buyers are prepared to pay it. They know that the performance and luxury of a V8 sedan cost money. This number also helps show how the A8 L’s costs compare to others in its class.

Real-world expectations

The EPA gives a standard benchmark, but real-world fuel economy changes based on how you drive and the conditions. If you mostly drive on the highway with a light foot, expect numbers close to the EPA estimates, but aggressive acceleration, short trips in the city, and idling can lower fuel economy. Hills and heavy traffic will also affect the numbers. The A8 L’s weight and engine size mean that driving style matters.

How it compares

The A8 L’s fuel economy is similar to other V8 full-size luxury sedans. The BMW 750i xDrive, with a 4.4L V8, gets an EPA-estimated 17 MPG combined. The Mercedes-Benz S 580 4MATIC, with its 4.0L V8, gets 19 MPG combined. These small differences might matter to some buyers, but these cars are chosen for more than just fuel efficiency. For better fuel economy, the plug-in hybrid Mercedes-Benz S 580e gets significantly better MPG, but costs more. See A8 MPG across all years to view the differences.

Tips to maximize efficiency

Avoid fast acceleration and hard braking. The A8 L is heavy and takes a lot of energy to speed up, and hard braking wastes that energy. Slowly use the gas and brakes to save fuel. Watch the traffic and keep a steady speed when you can.

Use the A8 L’s drive mode settings. “Efficiency” mode sets the engine and transmission for fuel saving. It might make the throttle less responsive, but it can help on longer drives. Remember to switch out of “Dynamic” mode unless you want quicker performance.

Keep your tires inflated properly. Low tires increase rolling resistance, making the engine work harder and use more fuel. Check your tire pressure often and inflate them to the right levels, which you can find on the door or in the owner’s manual.

Keep the vehicle weight down. Extra weight in the trunk or passenger area adds to the vehicle’s weight and lowers fuel economy. Remove items you don’t need to carry regularly. This is helpful if you use the A8L’s trunk for storage often.

Use a more fuel-efficient vehicle for shorter trips if possible. The A8 L is very comfortable for long trips, but uses more fuel in the city. For short errands, a smaller car or a hybrid would be a better choice that results in less gas burned. For more fuel-efficient options, view all Audi fuel economy data.