For enhanced safety, the front seat shoulder belts of the Audi RS 3 are height-adjustable to accommodate a wide variety of driver and passenger heights. A better fit can prevent injuries and the increased comfort also encourages passengers to buckle up. The BMW M3 doesn’t offer height-adjustable seat belts.
Both the RS 3 and M3 have child safety locks to prevent children from opening the rear doors. The RS 3 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The M3’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.
To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the RS 3. But it costs extra on the M3.
Both the RS 3 and the M3 have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, post-collision automatic braking systems, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras and rear cross-path warning.
For its top level performance in IIHS driver and passenger-side small overlap frontal, moderate overlap frontal, side impact, roof strength and head restraint tests, its standard vehicle-to-vehicle front crash prevention system, its standard vehicle-to-pedestrian front crash prevention system, and its standard headlight’s “Good” rating, the Insurance Institute for Highway Safety grants the RS 3 its highest rating: “Top Safety Pick Plus” for 2022, a rating granted to only 101 vehicles tested by the IIHS. The M3 has not been tested, yet.