26 MPG combined is a reasonable, if not groundbreaking, figure for the 2023 Mercedes-Benz E450 4matic with its smooth 3.0L inline-six. This isn’t a car bought for outright frugality; it’s a smooth, confident, and technologically advanced sedan (or wagon) purchased by those who value refinement and a certain level of effortless performance. The E450 buyer likely prioritizes a quiet cabin, comfortable seats, and a prestigious badge, and accepts the fuel economy as a trade-off for the overall experience.

City and highway performance

The EPA estimates place the E450 at 23 MPG in the city and 31 MPG on the highway. The city figure reflects the engine’s responsiveness and the transmission’s need to shift frequently in stop-and-go traffic. The highway MPG, however, is a stronger showing. The 9-speed automatic allows the engine to cruise at lower RPMs, improving efficiency on longer trips. And the E450’s aerodynamic shape helps it slice through the air with minimal resistance at higher speeds. These figures are realistic based on the type of driving that an E450 typically sees, but they can vary significantly based on individual driving habits and traffic conditions.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2023 Mercedes-Benz E450 4matic at $2,250. This calculation is based on driving 15,000 miles per year, with 55% of those miles driven in the city and 45% on the highway. It also uses the national average fuel price at the time of calculation. Keep in mind that this is an estimate, and your actual fuel costs may be higher or lower depending on your individual driving habits and the price of gasoline in your area. If you drive significantly more or less than 15,000 miles per year, or if fuel prices fluctuate dramatically, your annual costs will vary accordingly.

Real-world expectations

While the EPA provides a standardized estimate, real-world fuel economy is rarely exactly what the sticker says. Drivers who frequently accelerate hard or spend a lot of time in congested traffic will likely see numbers closer to the lower end of the EPA range, or even slightly below. Conversely, those who prioritize smooth acceleration, anticipate traffic flow, and spend a good portion of their time on the open highway might achieve figures that are a bit better than the EPA estimates. The E450’s 4MATIC all-wheel-drive system, while beneficial for traction and stability, can also slightly decrease fuel economy compared to a rear-wheel-drive model.

How it compares

In the realm of mid-size luxury sedans, the E450’s fuel economy is competitive, but not class-leading. For example, the BMW 540i xDrive, another inline-six powered rival, is EPA-rated at 25 MPG combined. The Audi A6 55 TFSI, with its turbocharged V6, lands at 24 MPG combined. A Lexus ES 350, while not directly comparable in terms of performance or prestige, achieves a significantly better 26 MPG city / 35 MPG highway / 30 MPG combined by forgoing more powerful engine options. These differences matter to the type of buyer who cross-shops these vehicles, weighing fuel costs against their priorities for performance, luxury, and technology.

Tips to maximize efficiency

Take it easy on the accelerator. The E450’s turbocharged engine provides ample power, but aggressive acceleration significantly reduces fuel economy. Smooth, gradual acceleration not only saves fuel but also contributes to the vehicle’s overall refined driving experience.

Use the “Comfort” or “Eco” driving mode when appropriate. These modes optimize the engine and transmission for fuel efficiency, often relaxing throttle response and initiating earlier upshifts. Sport mode is fun, but comes at a cost.

Ensure your tires are properly inflated and regularly check them. Underinflated tires increase rolling resistance, which can reduce fuel economy by a noticeable margin. And rotating the tires regularly will improve fuel economy and extend tire life.

Avoid excessive idling. If you anticipate being stopped for more than a minute or two, turn off the engine. Modern engines are designed to restart quickly and efficiently, and idling wastes fuel unnecessarily.

Consider the weight you’re carrying. Removing unnecessary items from the trunk or rear seats reduces the overall weight of the vehicle, which can contribute to improved fuel economy. This is especially important with larger, heavier vehicles like the E450.

Those considering the E450 should also review E450 MPG across all years to understand historical trends. For a wider perspective, explore all Mercedes Benz fuel economy data.