28 MPG combined is a respectable figure for the 2025 BMW M440i xDrive Convertible equipped with its 3.0L turbocharged four-cylinder engine. Let’s be honest: few buyers are cross-shopping this convertible based on fuel sipping abilities. This is a car for enjoying the open road, hearing the turbo spool up, and feeling the wind in your hair. Ultimately, these buyers prioritize performance and the prestige of the BMW badge over maximizing every single mile per gallon.

City and highway performance

The EPA estimates that the M440i xDrive Convertible will achieve 25 MPG in the city and 32 MPG on the highway. The city number reflects the stop-and-go nature of urban driving, which tends to penalize turbocharged engines. The 32 MPG highway figure, achieved during steady-state cruising, demonstrates this car’s ability to cover ground efficiently when not pushed hard. These two numbers really tell the story of how the M440i xDrive Convertible is likely to perform in the hands of its typical owner: decent efficiency commuting during the week, combined with the real-world potential to achieve over 30 MPG on weekend getaways, top down on scenic backroads.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2025 BMW M440i xDrive Convertible to be $2,050. This figure is derived from driving 15,000 miles per year and using national average fuel prices. Keep in mind that fuel prices fluctuate considerably, so this number is simply a baseline. If you drive more than 15,000 miles annually, or if fuel prices in your area are higher than the national average, your actual fuel costs will be higher. Conversely, lower mileage and living in an area with lower fuel costs mean you might spend less than $2,050 per year to keep your M440i fueled.

Real-world expectations

While the EPA estimates offer a useful baseline, your real-world fuel economy will depend heavily on your driving style and conditions. Aggressive acceleration, frequent hard braking, and extended idling will all negatively impact your MPG. Likewise, driving predominantly in congested city traffic will likely result in fuel economy closer to the 25 MPG city rating, while consistent highway driving should allow you to achieve numbers closer to the 32 MPG highway figure.

Owners focused on maximizing efficiency may even exceed the EPA’s highway estimate with careful driving, while those who enjoy the car’s performance potential will realistically see figures lower than the EPA combined estimate. And don’t forget that using higher octane fuel, as recommended by Bmw, will likely result in better performance as well as overall efficiency.

How it compares

The M440i xDrive Convertible occupies a specific niche. Compared to other similarly powered convertibles, its fuel economy is reasonable. For example, the V6-powered Ford Mustang GT Convertible is rated at 18 MPG city and 25 MPG highway. Even the four-cylinder Mustang EcoBoost Convertible achieves only 22 MPG city and 30 MPG highway. Within the BMW family, the Z4 M40i, with its six-cylinder engine, delivers comparable performance but with slightly worse fuel economy around 23 MPG combined.

For those considering alternatives to the M440i, all Bmw fuel economy data can be found on FuelEconomyHub.com. If you are considering this particular model, check out the M440I MPG across all years. When you are willing to sacrifice the convertible aspect, many coupes and sedans offer better efficiency, but these cars simply don’t offer the same open-air driving experience.

Tips to maximize efficiency

Anticipate traffic flow to avoid sudden acceleration and braking. Maintaining a smooth and consistent speed, especially on the highway, is important to optimizing fuel economy. Avoid excessive idling, which consumes fuel without covering any distance. If you anticipate being stopped for more than a minute or two, consider turning off the engine.

Use the car’s driving modes carefully. The Comfort or Eco Pro modes will generally prioritize fuel efficiency over performance, while Sport and Sport+ modes will emphasize power delivery and responsiveness, which will reduce MPG. Use cruise control on the highway to maintain a consistent speed and minimize unnecessary acceleration. This can significantly improve fuel economy on long trips.

Ensure that your tires are properly inflated. Underinflated tires increase rolling resistance, which reduces fuel efficiency. Check your tire pressure regularly and inflate them to the recommended pressure, typically found on a sticker inside the driver’s side doorjamb. Also, consider the weight you are carrying in the vehicle. Excess weight, even in the trunk, puts a strain on the engine and reduces fuel economy.

Keep up with routine maintenance. Regular oil changes, air filter replacements, and spark plug maintenance will ensure that your engine is running optimally and efficiently. A well-maintained engine will generally deliver better fuel economy than one that is neglected and be aware of the added resistance and fuel burn of the xDrive especially when driving in conditions where all-wheel drive is unnecessary. Keeping the car in two-wheel drive when possible will improve fuel economy by a bit.