Audi A6 vs BMW 7 Series: Specs Compared

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Audi A6 burns about $2,650 of fuel annually against $2,700 for the BMW 7 Series. That $50 yearly gap compounds to roughly $250 over five years and $400 over eight — often more than the price difference between two trims of the same vehicle, and the single largest running-cost line item separating these two.

City versus highway split: the BMW 7 Series is the stronger commuter at 25 mpg city, while the Audi A6 pulls ahead on the interstate at 38 mpg highway. If most of your driving is stop-and-go traffic the city figure is the one to weigh; for long-distance highway mileage the reverse is true, and the two vehicles effectively swap places depending on how you drive.

Powertrain choice: the Audi A6 is recorded with 3 distinct engine configurations (SIDI, SIDI; Mild Hybrid, 3.0), the BMW 7 Series with 4 (SIDI & PFI; Mild Hybrid, SIDI; Mild Hybrid, SIDI; PHEV). Across 36 recorded Audi A6 configurations and 69 for the BMW 7 Series, the wider the engine spread the more the real-world fuel efficiency depends on which version you actually buy, so check the specific model year and drivetrain rather than the headline number.

Drivetrain and class: the Audi A6 is offered with All-Wheel Drive, 4-Wheel Drive, Front-Wheel Drive, the BMW 7 Series with Rear-Wheel Drive, All-Wheel Drive. All-wheel drive typically costs one to two mpg combined against the same vehicle in front- or rear-wheel drive, which is worth remembering when the gap between these two is small. The EPA classes them as Midsize Cars and Large Cars respectively — the class drives the interior volume, cargo space and passenger space each one is measured against.

Tailpipe emissions: at their cleanest configurations the BMW 7 Series emits 130 g/mile of CO2 versus 311 g/mile for the Audi A6. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.