2021 head-to-head · Compact Car
2021 Kia Rio vs Mazda 3
MPG, range and what each one really costs you to fuel, from official EPA ratings and recalculated with your own gas and electricity prices.
The 2021 Kia Rio is the cheaper one to run. Driving 15,000 miles a year with $3.10/gal regular gas, it costs about $1,292 a year to fuel (36 MPG), versus $1,500 for the 2021 Mazda 3 (31 MPG). That's roughly $208 a year, or about $1,042 over five years.
Your numbers
Change these to match your driving and local prices. Every figure and chart on this page updates.
Fuel cost over 10 years
- Kia Rio
- Mazda 3
Side by side
| Kia Rio | Mazda 3 | |
|---|---|---|
| $1,292 | Your annual fuel cost | $1,500 |
| 36 MPG | Combined efficiency | 31 MPG |
| 33 MPG | City | 28 MPG |
| 41 MPG | Highway | 36 MPG |
| 91 cu ft | Passenger volume | 93 cu ft |
| 17 cu ft | Cargo volume | 13 cu ft |
| 249 g/mi | Tailpipe CO₂ (g/mi) | 287 g/mi |
| 8/10 | EPA fuel economy score | 7/10 |
| 8/10 | EPA greenhouse gas score | 7/10 |
| Gas | Powertrain | Gas |
| Regular gasoline | Fuel | Regular gasoline |
| 1.6L 4-cyl | Engine / motor | 2.0L 4-cyl |
| CVT | Transmission | 6-speed automatic |
| FWD | Drivetrain | FWD |
✓ marks the better value. EPA scores run 1–10 (10 is best). Volumes come from the EPA interior volume index and aren't published for every body style.
Kia Rio vs Mazda 3 across model years
- Kia Rio
- Mazda 3
Annual fuel cost of the most efficient configuration of each model year, at your prices. Click a point to open that year.
How they differ
Per EPA interior volume figures, the Kia Rio has more cargo space (17 vs. 13 cu ft).
Among 37 2021 compact cars, the Kia Rio ranks 7th and the Mazda 3 13th for lowest fuel cost.
Frequently asked questions
Which is more fuel-efficient, the 2021 Kia Rio or the 2021 Mazda 3?
Measured by cost to drive, the Kia Rio. The Kia Rio is rated 36 MPG combined and the Mazda 3 31 MPG (EPA, most efficient configuration of each).
How much does it cost to fuel the 2021 Kia Rio vs. the Mazda 3 per year?
At 15,000 miles a year with $3.10/gal regular gas, about $1,292 for the Kia Rio and $1,500 for the Mazda 3.
Which has more cargo space?
The Kia Rio, with 17 cu ft of luggage volume versus 13 cu ft (EPA interior volume index).
Kia Rio vs Mazda 3 in other years
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