For enhanced safety, the front and rear seat shoulder belts of the Kia K4 have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision and force limiters to limit the pressure the belts will exert on the passengers. The Audi S3 doesn’t offer pretensioners for its rear seat belts.
In the past twenty years hundreds of infants and young children have died after being left in vehicles, usually by accident. When turning the vehicle off, drivers of the K4 are reminded to check the back seat if they opened the rear door before starting out. The S3 doesn’t offer a back seat reminder.
With its standard Forward Collision-Avoidance Assist, the Kia K4 is better at preventing collisions with pedestrians than the Audi S3, according to the Insurance Institute for Highway Safety:
|
|
K4 |
S3 |
| Overall Evaluation |
GOOD |
MARGINAL |
|
|
Crossing Child - DAY |
|
| 12 MPH |
AVOIDED |
-11 MPH |
|
|
Crossing Adult - NIGHT |
|
| 12 MPH Brights |
AVOIDED |
-11 MPH |
| 12 MPH Low beams |
AVOIDED |
No Slowing |
| 25 MPH Brights |
AVOIDED |
-21 MPH |
| 25 MPH Low beams |
-16 MPH |
-11 MPH |
|
|
Parallel Adult - NIGHT |
|
| 25 MPH Brights |
AVOIDED |
-4 MPH |
| 25 MPH Low beams |
AVOIDED |
-8 MPH |
| 37 MPH Brights |
AVOIDED |
-14 MPH |
| Warning Issued-Brights |
1.9 sec |
1.5 sec |
| 37 MPH Low beams |
AVOIDED |
-1 MPH |
| Warning Issued-Low beams |
1.5 sec |
.3 sec |
In a Vehicle-to-Vehicle Frontal Crash Prevention 2.0 test conducted by the Insurance Institute for Highway Safety (IIHS), the Kia K4 achieved a “Acceptable” rating - the second highest possible - for its performance in forward collision warning and automatic braking systems, demonstrating its excellent capabilities in preventing collisions. The Audi S3 has not been tested.
Over 200 people are killed each year when backed over by motor vehicles. The K4 GT-Line Turbo offers optional Reverse Parking Collision-Avoidance Assist that uses rear sensors to monitor for objects to the rear and automatically applies the brakes to prevent a collision. The S3 doesn’t offer automatic braking for stationary objects directly to the rear.
The K4 GT-Line Turbo offers an optional Surround View Monitor to allow the driver to see objects all around the vehicle on a screen. The S3 only offers a rear monitor and front and rear parking sensors that beep or flash a light. That doesn’t help with obstacles to the sides.
The K4’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 S3 doesn’t offer a driver alert monitor.
Both the K4 and the S3 have standard driver and passenger frontal airbags, front and rear side-impact airbags, side-impact head airbags, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, rearview cameras, available blind spot warning systems and rear cross-path warning.
The Kia K4 (Built after January 2025) 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 S3 is not even a standard “Top Safety Pick” for 2025.