17 MPG combined. Frankly, nobody buys a 2021 Porsche 911 Turbo Cabriolet expecting Prius-like fuel consumption. They buy it for its relentless acceleration, its iconic shape, and the sheer thrill of open-air motoring with nearly 600 horsepower available. If lower fuel costs were a primary concern, they’d be looking at something entirely different, something likely without “Porsche” badging. This car is about performance, and the fuel consumption is simply part of what it costs to own it.

City and highway performance

Those 17 combined MPG break down to an EPA-estimated 15 MPG in the city and 20 MPG on the highway. The relatively small difference between city and highway figures highlights the duality of the 911 Turbo. Even tooling around town, the turbocharged 3.7-liter flat-six is always ready to unleash a surge of power, encouraging a heavier foot and thus, lower fuel economy. On the open road, while more consistent speeds help, resisting the urge to tap into the immense reserves of power requires significant restraint. The addictive nature of the acceleration makes achieving that 20 MPG highway rating a true test of willpower.

Annual fuel cost

The EPA estimates that the annual fuel cost for the 2021 Porsche 911 Turbo Cabriolet will be $3,400. This figure is based on driving 15,000 miles per year and using national average fuel prices. Of course, this is just an estimate, actual fuel costs can vary significantly depending on driving habits, local fuel prices, and the specific blend of city and highway driving. Someone who frequently uses launch control and spends most of their time in Sport Plus mode will undoubtedly see that $3,400 figure climb considerably. Conversely, a driver who prioritizes smooth acceleration and spends a majority of their time on the highway might achieve slightly better results.

Real-world expectations

Forget the EPA numbers. Real-world fuel economy in the 2021 911 Turbo Cabriolet is highly driver-dependent. If you’re consistently enjoying the car’s performance capabilities, expect numbers closer to 12-14 MPG. Gentle highway cruising might push you closer to the EPA estimate, but realistically, a number in the mid-teens is a more realistic expectation for most owners. These buyers aren’t agonizing over every tenth of a mile per gallon. They’re focused on the experience, the sound, and the sensation of driving one of the world’s finest sports cars.

How it compares

Compared to other high-performance convertibles, the 911 Turbo Cabriolet’s fuel economy is within the expected range. The V8-powered Mercedes-AMG SL 63, for example, achieves a combined 16 MPG. The BMW M8 Competition Convertible lands in a similar ballpark. You can see all Porsche fuel economy data here and 911 MPG across all years to get an idea of where this particular trim falls in the overall lineup. The Audi R8 Spyder, with its naturally aspirated V10, drinks even more fuel. The reality is, if you’re cross-shopping these types of cars, fuel economy is unlikely to be a deciding factor; the differences are relatively marginal compared to the significant price tags and performance capabilities.

Tips to maximize efficiency

While fuel economy might not be an important priority, there are still ways to squeeze a bit more range out of each tank. Avoid aggressive acceleration and braking. The 911 Turbo Cabriolet’s immense power is readily accessible, but using it frequently takes a significant toll on fuel consumption. Drive smoothly and anticipate traffic flow to minimize unnecessary stops and starts.

Use the car’s driving modes carefully. While Sport and Sport Plus modes offer enhanced throttle response and more aggressive shift patterns, they also consume more fuel. Opt for Normal mode during casual cruising to allow the car to prioritize efficiency; the engine management system is designed to optimize fuel economy in this mode.

Ensure that your tires are properly inflated, underinflated tires increase rolling resistance, which leads to a decrease in fuel economy. Check your tire pressure regularly and inflate them to the manufacturer’s recommended specifications, often found on a sticker inside the driver’s side door.

Avoid carrying unnecessary weight. The heavier the car, the more fuel it consumes. Remove any items from the trunk or passenger compartment that are not essential. Even seemingly small amounts of extra weight can add up over time.

Consider using premium fuel, even though it’s not strictly required. While the 911 Turbo Cabriolet is designed to run on standard unleaded gasoline, using premium fuel can potentially improve performance and fuel economy slightly, depending on the specific driving conditions and fuel quality. Consult your owner’s manual for more information.