2021 Mazda CX-9 4WD MPG & Specs — Real Fuel Cost
Quick answer
The 2021 Mazda CX-9 4WD gets an EPA-estimated 20/26 MPG (city/highway) and 23 MPG combined, with an estimated $2,650/year fuel cost and 391 g/mi CO₂. Engine: 2.5 L 4-cyl.
The 2021 Mazda CX-9 4WD with the 2.5-liter 4-cylinder regular gasoline engine returns an EPA-estimated 20 MPG in the city and 26 MPG on the highway, for a combined 23 MPG. This page summarizes the official EPA fuel-economy and emissions data for this configuration.
| Engine | 2.5 L 4-cyl |
| Transmission | Automatic (S6) |
| Drive | 4-Wheel Drive |
| Fuel type | Regular Gasoline |
| Vehicle class | Small Sport Utility Vehicle 4WD |
| MPG — city | 20 |
| MPG — highway | 26 |
| MPG — combined | 23 |
| Annual fuel cost* | $2,650 |
| CO₂ tailpipe | 391 g/mi |
| EPA GHG score | 5/10 |
How efficient is it?
With a combined 23 MPG, the 2021 Mazda CX-9 4WD sits in the moderate range for fuel economy. That is roughly 26% thirstier than the typical Small Sport Utility Vehicle 4WD of its era (31 MPG class average) — expect higher fuel bills than class-average alternatives.
Fuel economy and running costs
At about $2,650 per year in fuel (EPA estimate, 15,000 mi/yr), fuel is a major part of the cost of owning the 2021 Mazda CX-9 4WD. Over five years that is roughly $13,250 at today's prices — before insurance, maintenance, and depreciation.
Emissions
The 2021 Mazda CX-9 4WD emits approximately 391 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.