26 MPG combined won’t win any hypermiling awards, but it’s acceptable for the 2021 Mercedes-Benz E450 Coupe. This car isn’t designed for maximum efficiency; it’s a stylish, comfortable, and quick grand tourer intended for effortless trips and looking good while doing it. Buyers in this segment prioritize curb appeal, a luxurious interior, and a smooth ride, and are generally willing to accept average fuel economy as a tradeoff.

City and highway performance

The EPA estimates the E450 Coupe will achieve 23 MPG in the city and 31 MPG on the highway. The highway figure, in particular, is respectable thanks to the 9-speed automatic transmission allowing the engine to cruise at low RPMs. The 3.0L inline-six is a smooth operator, and even when pushed, the fuel economy rarely dips into truly alarming territory. City driving sees the MPG drop slightly, but the engine’s ample low-end torque means you won’t need to constantly bury your foot to keep up with traffic, helping to mitigate fuel consumption in stop-and-go situations. The E450 is happy to stretch its legs on long highway drives, where it shines.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2021 Mercedes-Benz E450 Coupe at $2,250. This figure is based on driving 15,000 miles per year and using national average fuel prices for premium gasoline, which the E450 requires. Individual costs will vary depending on driving habits, local fuel prices, and the number of miles driven annually. For those who drive significantly more or less than 15,000 miles, the actual cost will be proportionately higher or lower.

Real-world expectations

While the EPA provides a standardized estimate, real-world fuel economy can vary. If you drive with a light foot and spend time on the highway, expect figures close to the EPA estimates. More aggressive driving, frequent short trips, and prolonged idling will negatively impact fuel economy. Some owners report achieving highway figures slightly better than the EPA estimate on long road trips, indicating that the E450 Coupe is a capable and relatively efficient long-distance cruiser. Remember to check all Mercedes Benz fuel economy data to see trends across the whole brand.

How it compares

The E450 Coupe sits in a segment of luxury coupes where fuel economy isn’t always the primary concern, but comparing it to its rivals puts its efficiency into perspective. The BMW 440i Coupe, with its 3.0L inline-six, achieves a similar 26 MPG combined. The Audi A5 Coupe, powered by a 2.0L turbo four, offers a slightly better 28 MPG combined, but lacks the power and refinement of the E450’s six-cylinder engine. The Lexus RC 350, while known for its reliability, lags behind at 23 MPG combined with its V6 engine. Those shopping around should also compare E450 MPG across all years to see if there are noticeable differences.

Tips to maximize efficiency

Take advantage of the E450’s “Comfort” driving mode. This setting optimizes the engine and transmission for smooth, efficient driving, prioritizing lower RPMs and earlier gear changes. While the “Sport” and “Sport+” modes are tempting, they significantly increase fuel consumption.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, which directly reduces fuel economy. Check your tire pressure regularly and inflate them to the recommended pressure found on the doorjamb sticker.

Minimize unnecessary weight in the vehicle. Carrying excessive cargo adds weight, requiring the engine to work harder and burning more fuel. Remove any items you don’t need to carry regularly.

Avoid aggressive driving habits. Rapid acceleration and hard braking consume significantly more fuel. Drive smoothly and anticipate traffic conditions to maintain a steady speed and minimize unnecessary acceleration and braking.

Consider using cruise control on the highway. Cruise control helps maintain a constant speed, which can improve fuel economy by minimizing fluctuations in throttle input, especially on relatively flat terrain.