BMW M240i Convertible
22.5 MPG The 2021 BMW M240i Convertible is EPA-rated at 22.5 MPG combined (20 city / 28.5 highway). Over 15,000 miles a year that is about 667 gallons, $2133 a year in fuel, or $0.142 per mile at $3.20/gal.
Across its full 2017–2021 run it averages 23.1 MPG, falling by 1.5 MPG over 5 model years.
Running cost at different fuel prices and mileages
The figure everyone actually wants, and the one the EPA does not publish — because it depends on a fuel price no agency will commit to.
| Fuel price | Per mile | 10,000 mi/yr | 15,000 mi/yr | 20,000 mi/yr |
|---|---|---|---|---|
| $2.50/gal | $0.111 | $1111 | $1667 | $2222 |
| $3.00/gal | $0.133 | $1333 | $2000 | $2667 |
| $3.20/gal | $0.142 | $1422 | $2133 | $2844 |
| $3.50/gal | $0.156 | $1556 | $2333 | $3111 |
| $4.00/gal | $0.178 | $1778 | $2667 | $3556 |
| $4.50/gal | $0.200 | $2000 | $3000 | $4000 |
| $5.00/gal | $0.222 | $2222 | $3333 | $4444 |
Every model year
| Year | Combined | City | Highway | EPA fuel cost/yr | CO₂ g/mi | Trims |
|---|---|---|---|---|---|---|
| 2021 | 22.5 MPG | 20 | 28.5 | $3425 | 388 | 2 |
| 2020 | 23.5 MPG | 20.5 | 28.5 | $3300 | 381 | 2 |
| 2019 | 22.5 MPG | 19.5 | 28.5 | $3425 | 390 | 2 |
| 2018 | 23 MPG | 19.5 | 28.5 | $3350 | 387 | 2 |
| 2017 | 24 MPG | 20 | 30.5 | $3225 | 377 | 2 |
Where a model year offered several engines or drivetrains, the figure is the average across all EPA-tested trims that year — the trim count is shown so you can see how much averaging is involved.
How it compares in its class
Among the 229 subcompact cars models tracked here, the BMW M240i Convertible ranks 115 on current figures, against a class average of 24.2 MPG.
Closest more-efficient alternatives in the same class: Mitsubishi Cordia (22.7), Mitsubishi Tredia (22.7), Subaru XT (22.7), Audi RS 3 (23), BMW 640i Convertible (23).
Tailpipe CO₂ is rated at 388 grams per mile, which works out to roughly 5.8 tonnes a year at 15,000 miles.
Questions
What MPG does the BMW M240i Convertible get?
The 2021 BMW M240i Convertible is rated at 22.5 MPG combined by the EPA — 20 city and 28.5 highway. Across all 5 model years in the database it averages 23.1 MPG, ranging from 21 to 25 depending on year and trim.
How much does a BMW M240i Convertible cost in fuel per year?
At 22.5 MPG and 15,000 miles a year, it burns about 667 gallons — roughly $2133 a year with fuel at $3.20 a gallon, or $0.142 per mile. The EPA's own published annual figure for the 2021 model is $3425.
Has the BMW M240i Convertible become more efficient over time?
No — it has actually gone backwards, from 24 MPG in 2017 to 22.5 in 2021. That usually reflects the model growing heavier, more powerful, or moving upmarket rather than the engineering getting worse.
Is the BMW M240i Convertible efficient for its class?
It ranks 115 of 229 in the Subcompact Cars class on current figures, against a class average of 24.2 MPG. That is 1.7 worse than typical for the class.
EPA test figures from fueleconomy.gov. Cost per mile and annual fuel spend are computed at a reference price of $3.20 per gallon — use your own price. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.