Mazda CX-3 Fuel Economy (MPG)
What is the real-world gas mileage of a 2021 Mazda CX-3?
The 2021 Mazda CX-3 gets up to 31 MPG combined (29 city / 34 highway) in EPA testing.
Latest model year (2021):
The Mazda CX-3 gets up to 31 MPG combined (29 city / 34 highway) in the Auto (S6), 4 cyl, 2.0 L trim.
Mazda CX-3 MPG — All Years
| Year | Trim | Engine | Fuel | City (MPG) | Hwy (MPG) | Combined (MPG) |
|---|---|---|---|---|---|---|
| 2021Config 1 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 34 | 31 |
| 2021Config 2 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 27 | 32 | 29 |
| 2020Config 1 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 34 | 31 |
| 2020Config 2 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 27 | 32 | 29 |
| 2019Config 1 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 34 | 31 |
| 2019Config 2 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 27 | 32 | 29 |
| 2018Config 1 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 34 | 31 |
| 2018Config 2 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 27 | 32 | 29 |
| 2017Config 1 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 34 | 31 |
| 2017Config 2 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 27 | 32 | 29 |
| 2016Config 1 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 35 | 31 |
| 2016Config 2 of 2 | Auto (S6), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 27 | 32 | 29 |
Data sourced from fueleconomy.gov (U.S. Department of Energy). MPG figures are EPA-tested. Fuel costs are estimates based on average fuel prices and 15,000 miles/year.
Mazda CX-3 data analysis
How Mazda CX-3 combined fuel economy varies
Across 12 configurations recorded for the 2016 through 2021 Mazda CX-3, combined fuel economy runs from 29 MPG to 31 MPG. The strongest figure belongs to the 2016 Mazda CX-3 (Auto (S6), 4 cyl, 2.0 L) at 31 MPG, and the weakest to the 2021 car (Auto (S6), 4 cyl, 2.0 L) at 29 MPG — a spread of 7%. The narrow spread means any year of the Mazda CX-3 in this table behaves much like the others, so you can shop on price, condition and mileage rather than chasing a particular model year.
What changed for 2021
Average combined fuel economy for the 2021 Mazda CX-3 is 30 MPG, against 30 MPG for the 2020 car — it held flat. A carry-over year like this usually means no powertrain or structural change, so an older example is the cheaper way into the same specification.
How to read this Mazda CX-3 data
This page lists every 2016 through 2021 Mazda CX-3 record we hold for this measurement — 12 rows in total, one per configuration and model year rather than a single headline figure. Figures are published as the source agency records them: we do not round, average or interpolate missing years, and a year that is absent from the table is a year with no published measurement rather than a zero. Where a manufacturer offered several drivetrains or body styles in the same year, each appears on its own row, because those variants rarely share the same numbers.
Configurations behind these Mazda CX-3 numbers
The 2016 through 2021 Mazda CX-3 entries here span 6 model years of published measurements for this figure. 2021 is the busiest model year in the record with 2 separate measured configurations, which is why a single quoted combined fuel economy figure for that year is rarely the one that matches the car in front of you. Match the row to the exact drivetrain, body style and engine on the window sticker or VIN before relying on the number, and use the comparison links below to see how those same configurations line up against rival models.
Where these Mazda CX-3 figures come from
Every value on this page is loaded from federal open data — EPA fuel economy submissions, NHTSA vehicle and crash-test records, and manufacturer specification filings — rather than dealer listings or copied editorial content. The Mazda CX-3 record refreshes as the agencies publish, which typically means new model-year rows appear in the autumn and crash-test results follow through the model year as vehicles are tested. Because certification data is filed per configuration, treat any single headline number for this vehicle with caution: the figure that applies to a specific car depends on its engine, drivetrain, body style and model year, all of which are listed separately above. If a number here disagrees with a brochure, the brochure is usually quoting the best available configuration rather than the one being sold.
Official Factory Specs vs. AutoSpecData Expert Benchmarks
The EPA highway loop never holds interstate speed. Here is what the same engine does when you sit on the cruise control.
| Cruise speed | EPA highway spec | AutoSpecData adjusted MPG | Fuel you lose |
|---|---|---|---|
| 60 mph | 35 MPG | 35 MPG | 0% |
| 65 mph | 35 MPG | 32.6 MPG | 7% |
| 70 mph | 35 MPG | 30.4 MPG | 13% |
| 75 mph | 35 MPG | 28.3 MPG | 19% |
| 80 mph | 35 MPG | 26.4 MPG | 25% |
Our Real-World Speed MPG Adjuster re-scales the Mazda CX-3 EPA highway result with a quadratic drag term (mpg = hwy ÷ (1 + k·(v² − 60²)/60²), k = 0.55 for trucks, SUVs and vans, 0.42 for cars). Wind, roof racks, and a heavy right foot make it worse, never better.
Frequently Asked Questions About CX-3 MPG
What is the MPG of the Mazda CX-3?
The Mazda CX-3 gets up to 31 MPG combined (29 city / 34 highway) in the 2021 model year. Fuel economy varies by engine and trim — see the full table above for details.
Which Mazda CX-3 trim has the best fuel economy?
The Auto (S6), 4 cyl, 2.0 L trim offers the best combined fuel economy at 31 MPG. Smaller engines and front-wheel-drive configurations typically achieve the highest MPG.