Against 41 other Plug-in hybrid cars rated 2019–2021, the i3 trails their 36.5 mpg average by 5.5 mpg, about $187 a year.
Every BMW i3 engine, compared
The BMW i3 was rated in a single specification, so its gas mileage does not vary by version — only by model year. Yearly cost assumes 12,000 miles at $3.20 a gallon.
| Engine | Combined | City / Highway | Years | Fuel per year |
|---|---|---|---|---|
| 0.6L 2-cyl Plug-in hybrid | 35.6 / 33.8 | 2014–2021 | $1,097 |
What that actually costs
Against its rivals in the same model years, the Honda Civic gets 36 mpg, the Nissan Sentra 33 mpg and the Audi A3 31 mpg, next to 31 mpg for the 2021 i3.
| Measure | Value |
|---|---|
| Cost per mile (2021) | $0.103 |
| Fuel per year | $1,239 |
| Fuel over five years | $6,195 |
| Against other Plug-in hybrid cars, 2019–2021 | +$187 a year |
| EPA's own estimate | $2,238 a year |
City or highway — who is this car for
The 2021 BMW i3 gives up 1 mpg in town: 31 on the highway against 30 in the city, $41 a year if every mile were city driving.
| Measure | Value | Reading |
|---|---|---|
| City (2021) | 30 mpg | $1,280 a year if you only drive in town |
| Highway | 31 mpg | $1,239 a year if you mostly commute |
| Gap | +1 mpg (3%) | Narrow — equally happy either way |
How the i3 changed over the years
The i3 peaked in 2016 at 39 mpg (41 city, 37 highway) and was at its thirstiest in 2021 at 31 — 8 mpg apart, or $254 a year in fuel between buying one year and the other. The 2021 car does 31. The biggest single-year change came in 2019: 35 to 31 mpg.
| Model year | Combined | City / Highway | Engines offered | Fuel per year |
|---|---|---|---|---|
| 2021 | 30 / 31 | 1 | $1,239 | |
| 2020 | 30 / 31 | 1 | $1,239 | |
| 2019 | 30 / 31 | 1 | $1,239 | |
| 2018 | 36 / 33 | 1 | $1,097 | |
| 2017 | 36 / 33 | 1 | $1,097 | |
| 2016 | 41 / 37 | 1 | $985 | |
| 2015 | 41 / 37 | 1 | $985 | |
| 2014 | 41 / 37 | 1 | $985 |
MPG is a number. Dollars per year is the answer.
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How we count
This page rests on 8 EPA ratings of the BMW i3 — 1 engine across 2014–2021. The mileage is EPA's laboratory figure, unchanged; the yearly bill is ours, at 12,000 miles and $3.20 a gallon, against EPA's own estimate of $2,238. Full method.
Frequently asked questions
What mpg does the 2021 BMW i3 get?
31 mpg combined, 30 city and 31 highway, per EPA. Across every year since 2014 the i3 has averaged 35 mpg.
Is the 2021 i3 more efficient than the 2020?
About the same: 31 against 31 mpg combined.
Which i3 year has the best gas mileage?
The 2016, at 39 mpg combined (41 city, 37 highway).
Does the i3 get better gas mileage than the Honda Civic?
No: 31 mpg for the 2021 i3 against 36 for the 2022 Honda Civic, about $172 a year more to run.
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