17 MPG combined is probably not the first thing on the mind of a 2024 BMW M8 Competition Convertible owner. This car is bred for exhilaration, a sun-drenched monument to speed and sound. Fuel economy is a secondary concern, tolerated by drivers who want a thrilling experience more than saving money. The M8 Convertible isn’t about saving money at the pump; it’s about indulging in a world-class performance car.

City and highway performance

EPA estimates peg the M8 Competition Convertible at 15 MPG in the city and 22 MPG on the highway. The city figure reflects the frequent stops of urban driving, where the M8’s power is often limited by traffic. Even gentle throttle inputs in city environments, however, burn fuel quickly. The highway number is more appealing, but only when the car is used as a relaxed grand tourer and not pushed to its performance limits. With the top down and the open road ahead, resisting the urge to unleash the 4.4L twin-turbocharged V8 is a constant battle, and one that rarely results in 22 MPG.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2024 BMW M8 Competition Convertible at $3,400. This figure is calculated based on driving 15,000 miles per year, with 55% of those miles driven in the city and 45% on the highway, using national average fuel prices. Remember that this is an estimate. Drivers who spend more time in the city or accelerate more aggressively will undoubtedly exceed this amount. Also, premium unleaded fuel is required, adding further to the cost.

Real-world expectations

Don’t expect to consistently achieve the EPA numbers in real-world driving. Owners who regularly enjoy the M8’s performance will likely see fuel economy figures closer to the low teens. Spirited acceleration, frequent use of Sport or Sport+ driving modes, and a general disregard for fuel-saving techniques will lower the average MPG. The M8 Convertible handles like a performance machine, so driving it like one will inevitably affect fuel consumption. Some M8 owners report exceeding EPA estimates, but those are the unusual cases of very restrained driving on long highway cruises.

How it compares

The M8 Competition Convertible exists in a segment where fuel economy is less important than performance and prestige, but comparing similar cars puts the numbers into perspective. The Porsche 911 Turbo S Cabriolet, for example, manages a slightly better 17 MPG city and 24 MPG highway. The Mercedes-AMG SL63, with similar power output, returns about 16 MPG city and 23 MPG highway. What does this mean for the M8 buyer? Probably very little. If someone is cross-shopping these vehicles, they usually have a price point and a certain look in mind. While a mile or two per gallon might be a tiny factor, the experience, the brand image, and the emotional connection to the car are the only things that matter.

Tips to maximize efficiency

Fuel economy isn’t the M8’s best quality, but there are a few steps you can take to conserve fuel. Engage the “Comfort” driving mode, which softens throttle response and optimizes shift points for efficiency. This alone can make a difference, particularly in city driving, though it does reduce the M8’s ferocious character.

Be careful how you accelerate. Gradual and smooth acceleration consumes less fuel than aggressive launches. The M8’s power makes it easy to accelerate quickly, but exercising restraint will help improve your MPG. Anticipate traffic conditions and maintain a steady speed whenever possible.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, which reduces fuel economy. Check your tire pressure regularly and inflate them to the recommended levels, which can be found on the driver’s side doorjamb. It is important to have this checked so you get the best efficiency possible.

Avoid unnecessary idling. If you’re stopped for more than a minute, turn off the engine. Modern engines are designed to restart quickly and efficiently, and idling wastes fuel. Stop-start technology typically helps with this issue, but it can be turned off, so make sure it is engaged for maximum fuel efficiency during city driving.

Consider the route you’re taking. Opt for routes with fewer stops and starts whenever possible. Highway driving generally yields better fuel economy than city driving, so avoid congested urban areas if you’re trying to save fuel. See all Bmw fuel economy data and M8 MPG across all years on our site.