BMW · Subcompact cars · Gasoline
BMW 8 Series: MPG and annual fuel cost, 2026
In model year 2026 the BMW 8 Series is rated at 24 MPG combined, 9th of 13 subcompact cars, in the lower half.
- 24MPG combined9th of 13 in class
- $3,400a year in fuel9th of 13 in class
- 368g/mile CO2
Where it stands
Compared only with the gasoline models of its class it is 5th of 9 gasoline subcompact cars, in the upper half, ahead of 50% of the others. The median of that narrower group is 24 MPG, against 26 MPG for all subcompact cars together.
Across every class it is tied for 72nd of 180 gasoline models, in the upper half.
BMW has 23 models in the 2026 data. This one ranks 16th of them on combined rating, against a make median of 28 MPG.
In its class, just ahead of it is the Audi S3 at 26 MPG and just behind it is the Audi RS at 23 MPG.
Fuel cost and CO2
Assuming 15,000 miles a year with 55% of them in the city and premium gasoline at $5.48 per gallon, fuelling the most efficient version comes to about $3,400 a year. That is $350 more than the subcompact cars median of $3,050.
It emits 368 g of CO2 per mile from the tailpipe; the subcompact cars median is 341, a difference of 27 g/mile.
Rated versions
In the city the most efficient version is rated 21 and on the highway 29, 8 better on the open road. 9 versions are rated for 2026. The most efficient, 840i Convertible: 3.0 L, 6 cyl, Automatic (S8), RWD, gets 24 MPG; the least efficient listed, M850i xDrive Gran Coupe: 4.4 L, 8 cyl, Automatic (S8), AWD, gets 19 MPG, a gap of 5 MPG. With the file's assumptions that gap is worth about $950 a year in fuel.
| Version | Combined MPG | City MPG | Highway MPG | Annual fuel cost | CO2 g/mile |
|---|---|---|---|---|---|
| 840i Convertible: 3.0 L, 6 cyl, Automatic (S8), RWD | 24 | 21 | 29 | $3,400 | 368 |
| 840i Coupe: 3.0 L, 6 cyl, Automatic (S8), RWD | 24 | 21 | 29 | $3,400 | 368 |
| 840i Gran Coupe: 3.0 L, 6 cyl, Automatic (S8), RWD | 24 | 21 | 29 | $3,400 | 368 |
| 840i xDrive Convertible: 3.0 L, 6 cyl, Automatic (S8), AWD | 24 | 21 | 29 | $3,400 | 373 |
| 840i xDrive Coupe: 3.0 L, 6 cyl, Automatic (S8), AWD | 24 | 21 | 29 | $3,400 | 373 |
| 840i xDrive Gran Coupe: 3.0 L, 6 cyl, Automatic (S8), AWD | 24 | 21 | 29 | $3,400 | 373 |
| M850i xDrive Convertible: 4.4 L, 8 cyl, Automatic (S8), AWD | 19 | 17 | 24 | $4,350 | 456 |
| M850i xDrive Coupe: 4.4 L, 8 cyl, Automatic (S8), AWD | 19 | 17 | 24 | $4,350 | 456 |
| M850i xDrive Gran Coupe: 4.4 L, 8 cyl, Automatic (S8), AWD | 19 | 17 | 24 | $4,350 | 456 |
Year by year
The BMW 8 Series is in the data for 8 of the 8 model years from 2019 to 2026. Its best combined rating went from 20 in 2019 to 24 MPG in 2026, up 4 MPG. The highest figure came in 2020, at 25. The number of rated versions grew from 2 to 9. Fuel cost for the best version is $3,400 in the latest data against $4,100 in 2019, although the file applies today's fuel prices to every model year, so that change comes from the rating, not from prices.
| Model year | Versions | Best MPG | Lowest MPG | Fuel cost | CO2 g/mi | Class median |
|---|---|---|---|---|---|---|
| 2026 | 9 | 24 | 19 | $3,400 | 368 | 26 |
| 2025 | 10 | 24 | 19 | $3,400 | 368 | 26 |
| 2024 | 10 | 24 | 19 | $3,400 | 374 | 26 |
| 2023 | 10 | 24 | 19 | $3,400 | 374 | 25 |
| 2022 | 10 | 25 | 19 | $3,300 | 360 | 26 |
| 2021 | 7 | 25 | 20 | $3,300 | 360 | 26 |
| 2020 | 6 | 25 | 23 | $3,300 | 347 | 26 |
| 2019 | 2 | 20 | 20 | $4,100 | 434 | 25 |
Similar models
| Model | Powertrain | Combined MPG | Annual fuel cost | Model year |
|---|---|---|---|---|
| Audi RS | Gasoline | 23 | $3,550 | 2026 |
| Audi S3 | Gasoline | 26 | $3,150 | 2026 |
| Ford Mustang | Gasoline | 26 | $2,600 | 2026 |
| Mercedes-Benz CLE-Class | Hybrid | 27 | $3,050 | 2026 |
| Maserati Grancabrio | Gasoline | 20 | $4,100 | 2026 |
Compare and rank
Rankings: Subcompact cars, Gasoline, BMW.
Data: US EPA and DOE, as prepared in methods and data.