- Newest year: 2021
- Gas
- Small cars
2021 Roush Performance Mustang MPG & Fuel Cost
2 configurations · 14–15 MPG combined
15,000 mi/yr · premium gasoline $5.36/gal (U.S. average, Sep 2026)
Among the costliest small car configurations to fuel, MY2021. Ranked against all rated configurations, not sales-weighted.
2021 Roush Performance Mustang at a glance
The 2021 Roush Performance Mustang has 2 configurations in the EPA database, rated 14–15 MPG combined. The most efficient is the Mustang 5.0L 8-cyl supercharged RWD at 15 MPG, which costs about $5,480 a year to fuel at premium gasoline $5.36/gal (U.S. average, Sep 2026). Annual fuel cost across the configurations runs from $5,480 to $5,600, a $120 difference. The Mustang 5.0L 8-cyl supercharged RWD is among the costliest small car configurations to fuel for MY2021 (class median $3,210 a year).
What the 2021 Mustang 5.0L 8-cyl supercharged RWD costs to drive
Per month
$457
$5,480 a year ÷ 12
Per 25 miles
$9.13
Per 100 miles
$36.53
Five years
$27,400
5 × the yearly cost, prices held at today's level
vs the small car median
$2,270more a year
Class median $3,210 a year, MY2021
Based on 15,000 miles a year and premium gasoline $5.36/gal (U.S. average, Sep 2026).
2021 Roush Performance Mustang MPG
Gas configurations (2)
| Trim | Engine | Drive | City | Hwy | Comb. | $/yr |
|---|---|---|---|---|---|---|
| Mustang 5.0L 8-cyl supercharged RWD Automatic (S10) (Most efficient) | 5.0L 8-cyl supercharged | RWD | 12 | 19 | 15 | $5,480 |
| Mustang 5.0L 8-cyl supercharged RWD Manual 6-spd | 5.0L 8-cyl supercharged | RWD | 12 | 19 | 14 | $5,600 |
2 configurations require or recommend higher-octane gasoline and are costed at premium gasoline $5.36/gal (U.S. average, Sep 2026).
Fuel cost by state
Yearly cost of the Mustang 5.0L 8-cyl supercharged RWD: $6,540 in California and $4,760 in Texas, a $1,780 difference.
- California $6,540
- Washington $6,150
- New York $5,420
- Florida $5,010
- Texas $4,760
Similar cars
Closest combined MPG among MY2021 small car models.
Generations
Frequently asked questions
How does the 2021 Roush Performance Mustang compare with the previous generation?
The previous generation (2019 Roush Performance Mustang) is rated 15 MPG combined and costs $5,260–$5,470 a year to fuel; the 2021 model is rated 14–15 MPG and costs $5,480–$5,600 a year.
What gas mileage does the 2021 Roush Performance Mustang get?
EPA rates the 2021 Roush Performance Mustang at 14–15 MPG combined across 2 configurations. The most efficient, the Mustang 5.0L 8-cyl supercharged RWD, is rated 15 MPG combined (12 city / 19 highway).
How much does it cost to fuel a 2021 Roush Performance Mustang per year?
Driving 15,000 miles a year at premium gasoline $5.36/gal (U.S. average, Sep 2026), the Mustang 5.0L 8-cyl supercharged RWD costs about $5,480 a year. Across all 2 configurations the cost runs $5,480–$5,600 a year. That is a $120 difference between the cheapest and the costliest configuration.
How much does it cost to drive a 2021 Roush Performance Mustang 100 miles?
About $36.53 per 100 miles for the Mustang 5.0L 8-cyl supercharged RWD at premium gasoline $5.36/gal (U.S. average, Sep 2026), and between $36.53 and $37.33 across all configurations. That is the annual cost over 15,000 miles divided by 150.
Is the 2021 Roush Performance Mustang more efficient in the city or on the highway?
The Mustang 5.0L 8-cyl supercharged RWD is rated 12 city and 19 highway MPG, so it is more efficient on the highway, by 7 MPG.
How does the 2021 Roush Performance Mustang compare with other small car configurations?
The Mustang 5.0L 8-cyl supercharged RWD costs about $5,480 a year to fuel, $2,270 more than the class median of $3,210, and less than 0 of 10 small car configurations. The comparison covers all 298 rated small car configurations for MY2021, not weighted by sales.