The 2018 BMW 6 Series delivers an EPA-certified 19–23 MPG combined across 10 configurations. Estimated annual fuel costs range from $3,300 to $4,000.
Laboratory certification test values across engine, transmission, and drivetrain permutations
| Configuration / Model | Powertrain | Drivetrain | Transmission | City | Highway | Combined | Annual Fuel Cost | CO2 (g/mi) |
|---|---|---|---|---|---|---|---|---|
| 640i Convertible Premium | 3L 6-Cyl Gas | Rear-Wheel Drive | Automatic (S8) | 20 MPG | 29 MPG | 23 MPG | $3,300 | — |
| 640i Gran Coupe Premium | 3L 6-Cyl Gas | Rear-Wheel Drive | Automatic (S8) | 20 MPG | 29 MPG | 23 MPG | $3,300 | — |
| 640i xDrive Gran Turismo Premium | 3L 6-Cyl Gas | All-Wheel Drive | Automatic (S8) | 20 MPG | 28 MPG | 23 MPG | $3,300 | — |
| 640i xDrive Convertible Premium | 3L 6-Cyl Gas | All-Wheel Drive | Automatic (S8) | 19 MPG | 28 MPG | 22 MPG | $3,450 | — |
| 640i xDrive Gran Coupe Premium | 3L 6-Cyl Gas | All-Wheel Drive | Automatic (S8) | 19 MPG | 28 MPG | 22 MPG | $3,450 | — |
| 650i Convertible Premium | 4.4L 8-Cyl Gas | Rear-Wheel Drive | Automatic (S8) | 17 MPG | 25 MPG | 20 MPG | $3,800 | — |
| 650i Gran Coupe Premium | 4.4L 8-Cyl Gas | Rear-Wheel Drive | Automatic (S8) | 17 MPG | 25 MPG | 20 MPG | $3,800 | — |
| 650i xDrive Convertible Premium | 4.4L 8-Cyl Gas | All-Wheel Drive | Automatic (S8) | 16 MPG | 25 MPG | 19 MPG | $4,000 | — |
| 650i xDrive Gran Coupe Premium | 4.4L 8-Cyl Gas | All-Wheel Drive | Automatic (S8) | 16 MPG | 25 MPG | 19 MPG | $4,000 | — |
| Alpina B6 xDrive Gran Coupe Premium | 4.4L 8-Cyl Gas | All-Wheel Drive | Automatic (S8) | 16 MPG | 25 MPG | 19 MPG | $4,000 | — |
Standardized annual energy consumption and operating cost metrics based on 15,000 annual miles
Based on $3.50 per gallon regular gasoline
Estimated annual energy units needed for 15,000 miles
Compared to the average new vehicle over 5 years
Cross-reference safety ratings, owner defect complaints, and recall campaigns
Vehicle summary, specifications, and primary KPI metrics.
NHTSA 5-Star NCAP crash tests, rollover risk, and active driver assistance.
NHTSA consumer defect complaint filings by affected component.
Official safety recall notices, defects, and free repair instructions.
Direct, deterministic answers synthesized from verified United States government databases for the 2018 BMW 6 Series
The 2018 BMW 6 Series achieves an EPA-certified rating of 19 to 23 MPG combined across 10 certified configuration(s).
City ratings range from 16 to 20 MPG, and highway ratings range from 25 to 29 MPG.
Using AutoUtility's standardized operating cost model, estimated annual fueling and energy costs range between $3,300 and $4,000 for the 2018 BMW 6 Series.
Calculated under AutoUtility's standardized methodology (15,000 miles per year, 55% city / 45% highway driving, $3.50/gallon regular gasoline, $0.16/kWh electricity) using official EPA dynamometer consumption ratings.
Fuel economy ratings, electric range figures, and energy cost estimates on this page are retrieved directly from the United States Environmental Protection Agency (EPA) and U.S. Department of Energy (FuelEconomy.gov) certified vehicle database under 40 CFR Part 600.
Local Production Store Compiled: August 2026 • Deterministic Audited Dataset • Zero Dynamic External API Runtime Latency.