The A3’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The Sentra doesn’t offer pre-crash pretensioners.
Both the A3 and Sentra have child safety locks to prevent children from opening the rear doors. The A3 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 Sentra’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.
The A3 has a standard Secondary Collision Brake Assist, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The Sentra doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.
The A3 has all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The Sentra doesn’t offer all-wheel drive.
Both the A3 and Sentra have rear cross-traffic warning, but the A3 has Automatic Brake Activation (automatically applies the brakes) to better prevent a collision when backing near traffic. The Sentra’s Rear Cross Traffic Alert doesn’t automatically brake.
Both the A3 and the Sentra have standard driver and passenger frontal airbags, front and rear side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, blind spot warning systems, rear cross-path warning and available around view monitors.

