Owning the 2021 Mercedes-Benz AMG GLC63 4matic Plus Coupe means facing 17 MPG combined. Let’s be honest: nobody shelling out six figures for a hand-built AMG V8 is primarily concerned with how much gas it uses. This is a vehicle purchased for its ferocious performance, its head-turning looks, and its unmistakable AMG presence. The fuel bill, while not insignificant, is simply the price to join this exclusive club.

City and highway performance

The EPA estimates suggest 15 MPG in the city and 22 MPG on the highway. The relatively low city MPG is a direct consequence of the GLC63’s turbo lag-prone engine and its weight, both of which demand more fuel to get moving from a standstill. The highway figure, while better, still reflects the aerodynamic compromises inherent in the coupe body style and the ever-present temptation to exploit the engine’s power for easy passing. This isn’t a vehicle designed for maximizing fuel economy on long road trips, though maintaining a steady speed on the open highway will certainly yield better results than aggressive stop-and-go driving. Think of those numbers as a best-case scenario when driven gently.

Annual fuel cost

The EPA estimates the annual fuel cost at $3,400. This figure is calculated assuming 15,000 miles of driving per year, with a mix of city and highway miles, using national average fuel prices. Keep in mind that the GLC63 demands premium fuel, which further inflates the cost per gallon. Drivers who primarily use their GLC63 for short trips in congested urban areas can expect to exceed this annual fuel cost significantly. On the other hand, those who predominantly use it for longer highway commutes might see a slightly lower figure. Ultimately, driving style and local fuel prices will have the biggest impact on the real-world cost of fueling this high-performance machine.

Real-world expectations

Forget the EPA estimates. Owners who frequently unleash the GLC63’s 503 horsepower will see considerably lower MPG numbers than advertised. Expect figures closer to 12-14 MPG in mixed driving if you regularly tap into the available performance. The highly responsive throttle and addictive exhaust note constantly beckon drivers to push harder, which costs a substantial amount of fuel. It’s a trade-off most owners are willing to make, recognizing that the phenomenal driving experience justifies the reduced efficiency. Those with a particularly heavy right foot might even dip into the single digits on occasion, particularly during spirited weekend drives.

How it compares

Compared to its rivals, the GLC63 sits near the bottom of the fuel economy spectrum. The Porsche Macan Turbo achieves a combined 19 MPG, a slight improvement, while offering similar levels of performance and luxury. The BMW X3 M, with its inline-6 engine, manages around 16 MPG combined, comparable but still a touch better. The Alfa Romeo Stelvio Quadrifoglio, known for its own charismatic performance, also hover around this same fuel economy, rated at 17 MPG combined. These figures highlight one point: high-performance SUVs rarely prioritize fuel efficiency, but some offer a modest advantage, or come in with comparably poor fuel economy, as you shop the market. This comparison matters to buyers who, while prioritizing power and prestige, still appreciate some degree of efficiency or don’t want bragging rights for owning the least efficient model. See all Mercedes Benz fuel economy data for a wider view.

Tips to maximize efficiency

While the primary purpose of the AMG GLC63 isn’t fuel efficiency, there are still a few strategies to minimize fuel consumption.

Avoid aggressive acceleration and hard braking whenever possible. The GLC63’s immense power makes it easy to accelerate quickly, but each burst of acceleration burns extra fuel. Smooth and progressive throttle inputs help reduce unnecessary fuel waste.

Use the “Comfort” driving mode for everyday commuting. This mode softens throttle response and optimizes the transmission for fuel efficiency, reducing the temptation to unleash the engine’s full potential constantly. Resist the urge to switch to “Sport” or “Sport+” unless the situation calls for it.

Ensure proper tire inflation. Under-inflated tires increase rolling resistance, requiring the engine to work harder and consume more fuel. Check your tire pressure regularly and inflate to the recommended levels specified on the doorjamb or in the owner’s manual.

Minimize idling. Allowing the engine to idle for extended periods, especially when cold, wastes fuel. If you anticipate being stationary for more than a minute, it’s best to turn off the engine to conserve fuel. Even short periods of idling can add up over time and impact overall fuel economy.

Consider having the vehicle’s powertrain inspected. Although not unique to the GLC63, a car that has a tune or other modifications that do not meet factory specifications may demonstrate lowered fuel economy. See AMG MPG across all years for a broader look.