2021 Porsche Cayenne S MPG & Specs — Real Fuel Cost
Quick answer
The 2021 Porsche Cayenne S gets an EPA-estimated 18/22 MPG (city/highway) and 20 MPG combined, with an estimated $3,800/year fuel cost and 448 g/mi CO₂. Engine: 2.9 L 6-cyl.
The 2021 Porsche Cayenne S with the 2.9-liter 6-cylinder premium gasoline engine returns an EPA-estimated 18 MPG in the city and 22 MPG on the highway, for a combined 20 MPG. This page summarizes the official EPA fuel-economy and emissions data for this configuration.
| Engine | 2.9 L 6-cyl |
| Transmission | Automatic (S8) |
| Drive | All-Wheel Drive |
| Fuel type | Premium Gasoline |
| Vehicle class | Standard Sport Utility Vehicle 4WD |
| MPG — city | 18 |
| MPG — highway | 22 |
| MPG — combined | 20 |
| Annual fuel cost* | $3,800 |
| CO₂ tailpipe | 448 g/mi |
| EPA GHG score | 4/10 |
How efficient is it?
With a combined 20 MPG, the 2021 Porsche Cayenne S sits in the moderate range for fuel economy. That is roughly 34% thirstier than the typical Standard Sport Utility Vehicle 4WD of its era (30 MPG class average) — expect higher fuel bills than class-average alternatives.
Fuel economy and running costs
At about $3,800 per year in fuel (EPA estimate, 15,000 mi/yr), fuel is a major part of the cost of owning the 2021 Porsche Cayenne S. Over five years that is roughly $19,000 at today's prices — before insurance, maintenance, and depreciation.
Emissions
The 2021 Porsche Cayenne S emits approximately 448 grams of CO₂ per mile at the tailpipe, earning an EPA greenhouse-gas score of 4 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.