2018 Porsche 911 Carrera Cabriolet (Automatic) MPG & Specs
Quick answer
The 2018 Porsche 911 Carrera Cabriolet gets an EPA-estimated 22/28 MPG (city/highway) and 24 MPG combined, with an estimated $3,150/year fuel cost and 365 g/mi CO₂. Engine: 3 L 6-cyl.
The 2018 Porsche 911 Carrera Cabriolet with the 3-liter 6-cylinder premium gasoline engine returns an EPA-estimated 22 MPG in the city and 28 MPG on the highway, for a combined 24 MPG. This page summarizes the official EPA fuel-economy and emissions data for this configuration.
| Engine | 3 L 6-cyl |
| Transmission | Automatic (AM-S7) |
| Drive | Rear-Wheel Drive |
| Fuel type | Premium Gasoline |
| Vehicle class | Minicompact Cars |
| MPG — city | 22 |
| MPG — highway | 28 |
| MPG — combined | 24 |
| Annual fuel cost* | $3,150 |
| CO₂ tailpipe | 365 g/mi |
| EPA GHG score | 5/10 |
How efficient is it?
With a combined 24 MPG, the 2018 Porsche 911 Carrera Cabriolet sits in the moderate range for fuel economy. That is about average for its class (Minicompact Cars, 22 MPG average).
Fuel economy and running costs
At about $3,150 per year in fuel (EPA estimate, 15,000 mi/yr), fuel is a major part of the cost of owning the 2018 Porsche 911 Carrera Cabriolet. Over five years that is roughly $15,750 at today's prices — before insurance, maintenance, and depreciation.
Emissions
The 2018 Porsche 911 Carrera Cabriolet emits approximately 365 grams of CO₂ per mile at the tailpipe, earning an EPA greenhouse-gas score of 5 out of 10. Lower emissions generally track higher fuel economy.
How to read these numbers
EPA figures come from standardized laboratory test cycles and are the same estimates shown on the vehicle's window sticker. Your real-world mileage depends on driving style, conditions, fuel grade, and maintenance. Use combined MPG and annual fuel cost to compare vehicles fairly.