24 MPG combined is probably not the main reason someone buys a 2017 Porsche 911 Carrera 4S Cabriolet. It’s a compromise you make to experience incredible handling, amazing acceleration, and the unfiltered joy of open-top motoring in a well-engineered machine. The buyer of this car isn’t worried about tenths of a mile per gallon; they’re weighing the exhilaration it provides against the cost of its 3.0-liter flat-six.

City and highway performance

The EPA estimates the 2017 911 Carrera 4S Cabriolet at 21 MPG in the city and 28 MPG on the highway. This difference reflects the stop-and-go realities of urban driving. The turbocharged engine, while generally efficient, can use more gas when repeatedly accelerating from a standstill. On the open road, however, the intelligent programming of the 7-speed PDK automatic transmission allows the engine to settle into its most efficient range, resulting in a respectable highway figure. The “4S” designation also means all-wheel drive, which adds weight and complexity, gently increasing fuel consumption.

Annual fuel cost

The EPA calculates the annual fuel cost for the 2017 Porsche 911 Carrera 4S Cabriolet at $2,400. This figure is based on driving 15,000 miles per year and using the national average fuel price for premium unleaded gasoline, which this Porsche requires. Note that fuel prices fluctuate, and your actual driving habits may significantly affect your personal fuel expenditure. However, $2,400 provides a standardized benchmark for comparison and budgetary planning.

Real-world expectations

While the EPA provides consistent testing, real-world fuel economy often varies based on driving style, traffic conditions, and even tire pressure. A 911 driver who uses the car’s power often will see lower MPG than someone who primarily cruises on the highway. You can expect to see figures close to the EPA estimates if you drive conservatively and prioritize fuel efficiency. But trying to hold back from experiencing the car’s full potential requires significant restraint. For more information, visit our 911 MPG across all years page.

How it compares

Compared to other high-performance convertibles, the 2017 911 Carrera 4S Cabriolet’s fuel economy is generally competitive. A BMW M4 Convertible, with its turbocharged inline-six, achieves roughly the same 24 MPG combined. The Jaguar F-Type R Convertible, with a supercharged V8, drinks considerably more fuel, rated around 18 MPG combined. Even within the Porsche family, the base 911 Carrera Cabriolet, without all-wheel drive, might get an extra mile or two per gallon, but at the expense of all-weather grip. The choice then comes down to priorities: raw performance versus slightly better fuel economy. Explore all Porsche fuel economy data here.

Tips to maximize efficiency

Don’t constantly use Sport or Sport Plus modes. These settings sharpen throttle response and delay upshifts, maximizing performance but using more fuel. Leaving the car in standard or even Eco mode (if equipped) allows the transmission to prioritize fuel efficiency, especially during city driving.

Keep proper tire inflation. Underinflated tires increase rolling resistance, forcing the engine to work harder and consume more fuel. Check your tire pressure regularly and inflate them to the recommended levels, typically found on a sticker inside the driver’s side doorjamb.

Avoid unnecessary idling. If you anticipate being stopped for more than a minute, turn off the engine. Modern cars are designed to restart quickly and efficiently, and idling for extended periods wastes fuel and contributes to emissions.

Use cruise control on the highway. Maintaining a consistent speed minimizes unnecessary acceleration and deceleration, which can significantly improve fuel economy over longer distances. However, remain attentive and adjust your speed as needed to maintain a safe following distance.

Reduce weight. Carrying unnecessary weight in the car reduces fuel efficiency. Remove any items from the trunk or rear seats that you don’t need, such as golf clubs, extra luggage, or heavy tools; every pound counts.