19 MPG combined is not the main reason someone buys a 2015 BMW M4 Convertible. This car delivers a high-performance, wind-in-your-hair experience, and fuel economy is simply a necessary evil for enjoying the twin-turbocharged sound from under the hood. The target buyer for the M4 Convertible values driving thrills and open-air enjoyment above all else, someone for whom the car is likely a weekend toy, not a daily commuter. They appreciate the engineering and performance of the M division, they expect to pay a premium for that experience, and they are willing to accept the fuel bill that comes with it.

City and highway performance

The EPA estimates for the 2015 M4 Convertible are 17 MPG in the city and 24 MPG on the highway. These figures directly reflect how and where the car is driven. The city MPG reflects the energy required to repeatedly accelerate the M4’s curb weight from stops. The instant the turbochargers engage in city driving, fuel consumption climbs rapidly. On the open road, where the engine settles into a more relaxed cruise, the highway MPG demonstrates the efficiency potential of the 3.0-liter inline-six when not being pushed hard. The 7-speed automated manual transmission (AM-S7) helps efficiency when cruising, quickly upshifting to keep the engine in its sweet spot, though it can’t overcome the inherent thirst of a high-horsepower engine paired with a heavy car.

Annual fuel cost

The EPA estimates an annual fuel cost of $3,050 for the 2015 BMW M4 Convertible. This figure is based on driving 15,000 miles per year, with 55% of those miles driven in the city and 45% on the highway, using the national average fuel price for premium unleaded gasoline at the time of calculation. Real-world spending may vary significantly depending on individual driving habits, local fuel prices, and how aggressively the car is driven. Someone using the M4 Convertible primarily for weekend enjoyment might spend less, while a lead-footed driver could easily exceed that $3,050 estimate.

Real-world expectations

While the EPA provides a standardized benchmark, real-world conditions dramatically influence fuel economy. Expect numbers to change depending on driving style. Aggressive acceleration, frequent gear changes using the paddle shifters, and extended idling in traffic will all reduce MPG. Conversely, using the car’s Eco Pro mode, which dampens throttle response and optimizes transmission shifts for efficiency, can help achieve figures closer to the EPA estimates. However, it’s unlikely many M4 Convertible owners will spend much time in Eco Pro mode given the car’s performance.

How it compares

Compared to its direct competitors, the 2015 M4 Convertible’s fuel economy presents a specific picture. The Audi S5 Cabriolet with its supercharged V6 generally achieves around 18 MPG combined. The Mercedes-AMG C43 Cabriolet, another forced-induction V6 offering, typically delivers similar numbers, hovering around 19 MPG combined. The previous-generation BMW M3 Convertible (E93) with its naturally aspirated V8 was even less efficient, often struggling to reach 16 MPG combined. The M4’s twin-turbo six, despite its power, represents a step forward in fuel efficiency compared to earlier high-performance convertibles, a key point for some buyers. Check M4 MPG across all years to see how this model compares.

Tips to maximize efficiency

First, resist the urge to constantly exploit the engine’s power band. The M4 is exceptionally responsive, but every full-throttle acceleration run consumes a significant amount of fuel. Smooth, gradual acceleration will make a noticeable difference over time.

Ensure that the tires are properly inflated. Underinflated tires increase rolling resistance, forcing the engine to work harder and reducing fuel economy. Check the tire pressure regularly and inflate them to the recommended pressure listed on the driver’s side doorjamb.

Minimize unnecessary weight in the vehicle. Extra cargo in the trunk or passenger seat requires the engine to expend more energy to move the car, decreasing fuel efficiency. Remove any items that aren’t essential for daily driving.

Plan trips strategically. Combining errands into a single trip, rather than making multiple short trips, allows the engine to operate at its optimal temperature for a longer period, improving fuel efficiency. Avoid peak traffic times when possible to reduce idling.

Take advantage of the car’s Eco Pro mode when appropriate. While it diminishes the responsive feel of the car, Eco Pro can significantly improve fuel economy during relaxed cruising or highway driving. While it’s not how the M4 is *meant* to be driven, it’s a useful tool when fuel conservation takes priority. If you want to see all Bmw fuel economy data, browse our site.