Acura RDX vs Bentley Bentayga: Specs Compared

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Acura RDX burns about $3,150 of fuel annually against $3,600 for the Bentley Bentayga. That $450 yearly gap compounds to roughly $2,250 over five years and $3,600 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 and highway economy: the Acura RDX leads in both cycles — 22 mpg city and 28 mpg highway against 19 and 24 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the Acura RDX is recorded with 2 distinct engine configurations (SIDI, 3.5), the Bentley Bentayga with 3 (SIDI; PHEV, SIDI, SIDI & PFI). Across 34 recorded Acura RDX configurations and 26 for the Bentley Bentayga, 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 Acura RDX is offered with All-Wheel Drive, Front-Wheel Drive, 4-Wheel Drive, the Bentley Bentayga with 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 Small Sport Utility Vehicle 4WD and Standard Sport Utility Vehicle 4WD respectively — the class drives the interior volume, cargo space and passenger space each one is measured against.

Tailpipe emissions: at their cleanest configurations the Bentley Bentayga emits 203 g/mile of CO2 versus 370 g/mile for the Acura RDX. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.