The 2021 Mercedes-Benz AMG GLS63 4matic Plus gets 16 MPG combined. To be clear, fuel consumption isn’t a priority for most buyers of this powerful SUV. They are buying a handcrafted, twin-turbocharged V8 that delivers ferocious acceleration and a luxurious experience for seven occupants. The fuel bill is simply the price to pay for this level of performance and comfort.

City and highway performance

The EPA estimates 14 MPG in the city and 18 MPG on the highway. The city figure reflects the inefficiencies of stop-and-go driving with a large engine and a performance-tuned drivetrain. If you drive in urban areas, expect frequent visits to gas stations. The highway number, still unimpressive, is achievable while cruising. Keeping the AMG GLS63 in Comfort drive mode and resisting the urge to accelerate will produce better mileage, but can be hard to do.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2021 Mercedes-Benz AMG GLS63 at $3,600. This is based on driving 15,000 miles per year and using national average fuel prices. Premium fuel is required, which increases the cost. This is just an estimate, and your actual fuel expenses will vary depending on your driving, local fuel prices, and driving type. Someone who primarily drives in the city and accelerates quickly will likely exceed this estimate.

Real-world expectations

While the EPA figures provide a baseline, real-world fuel economy for the AMG GLS63 often falls short of official numbers. Resisting the engine’s power is hard, and the AMG’s weight affects efficiency even when driven moderately. The average can easily drop with headwinds, traffic, and elevation changes. However, buyers are not worried about a few extra gallons per week. They are buying performance, presence, and pampering, with fuel economy as a lower priority.

How it compares

The AMG GLS63’s fuel economy is similar to other high-performance SUVs, but there are choices that use less gas. For example, the BMW X7 M50i gets slightly better fuel mileage at 19 MPG combined. The Cadillac Escalade, even with its large V8, achieves similar numbers, but offers a different driving experience. The Range Rover Sport P525 offers comparable performance and luxury, but its economy is nearly identical. Buyers may also consider hybrid options, see all Mercedes Benz fuel economy data, which involves reduced performance for improved fuel efficiency. Anyone very concerned about MPG would shop for alternatives like the Tesla Model X, which has significantly better fuel efficiency, with a different set of compromises. You can also see AMG MPG across all years to see older models.

Tips to maximize efficiency

Even though MPG is not a high priority for an AMG GLS63, there are steps to take to reduce fuel consumption. Gentle acceleration is key. Avoid pressing the gas pedal hard, as this engages the turbochargers and consumes more fuel.

Use the drive mode selector effectively. The Comfort mode optimizes the engine and transmission settings for efficiency, while Sport and Sport+ prioritize performance. Staying in Comfort, especially during highway cruising, can improve your MPG.

Make sure your tires are properly inflated. Underinflated tires increase rolling resistance, which reduces fuel economy. Check your tire pressure regularly, and maintain the recommended inflation levels.

Minimize idling. Turn off the engine if you’re stopped for more than a minute. Modern engines are designed to restart quickly and efficiently, saving fuel compared to idling. Idling is particularly wasteful with a large engine.