Both the A5 and IS have child safety locks to prevent children from opening the rear doors. The A5 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 IS’ 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 A5 has a standard front seat center airbag, which deploys between the driver and front passenger, protecting them from injuries caused by striking each other in serious side impacts. The IS doesn’t offer front seat center airbags.
The A5 has standard whiplash protection, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the whiplash protection system moves the headrests forward to prevent neck and spine injuries. The IS doesn’t offer a whiplash protection system.
In a Vehicle-to-Vehicle Frontal Crash Prevention 2.0 test conducted by the Insurance Institute for Highway Safety (IIHS), the Audi A5 achieved a “Good” rating - the highest possible - for its performance in forward collision warning and automatic braking systems, demonstrating its excellent capabilities in preventing collisions. The Lexus IS has not been tested.
To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the A5. But it costs extra on the IS.
Earlier warning of stopped traffic, traffic signals, dangerous road conditions, weather, or accidents, can keep driver's safer and prevent crashes. The A5 has Car-to-X Services, a system that seamlessly communicates important warnings to the driver about impending danger, if they're available. The IS doesn’t offer a system that can receive automated systems from infrastructure.
To help make backing out of a parking space safer, the A5 has standard Rear Cross-Traffic Assist with Automatic Brake Activation, systems which detect vehicles approaching from the sides and can automatically apply the brakes to prevent a collision. Rear Cross-Traffic Braking costs extra on the IS.
The A5’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The IS doesn’t offer a driver alert monitor.
Both the A5 and the IS 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, post-collision automatic braking systems, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras and rear cross-path warning.
The Audi A5 has achieved the Insurance Institute for Highway Safety’s (IIHS) highest rating of “Top Safety Pick Plus” for the 2025 model year. This distinction is based on its exceptional performance in IIHS’ rigorous battery of safety tests. Specifically, it earned a “Good” rating in the latest, more stringent moderate overlap front crash test, a “Good” result in the updated side impact test, and a “Good” score in the revised pedestrian crash prevention test. The IS has not yet been fully evaluated by the IIHS for 2025.