Active and Passive Car Safety: Key Differences and 2025 Updates

Learn the difference between active and passive car safety. IIHS and Euro NCAP updates in 2025 highlight new crash tests, mandatory AEB, and driver-assist rules.

For many drivers, car safety still conjures images of solid bumpers and airbag-filled cabins. But today’s vehicles are built around two lines of defense: active safety that tries to stop a crash from happening, and passive safety that protects when the impact is unavoidable.

In the United States, IIHS calls passive safety crashworthiness—the strength of the body, belts, and airbags in a collision. Active safety, or crash avoidance & mitigation, covers technologies that intervene beforehand: automatic emergency braking (AEB), lane keeping, blind spot alerts, and more. Europe’s Euro NCAP uses a similar split: Safety Assist for active systems and Crash Protection for structural defense.

The past year has brought big shifts. In November 2024, the NHTSA finalized FMVSS No. 127, requiring AEB on all new light vehicles. And starting with model year 2026, America’s star ratings will include the performance of driver-assist features, with pedestrian protection playing a central role.

IIHS also toughened its tests in 2025. “Moderate Overlap 2.0” now factors in rear passengers, “Side 2.0” introduces a heavier crash at 37 mph, and the “Small Overlap” protocol reached its eighth version. At the same time, “Front Crash Prevention 2.0” arrived in April 2025, raising the bar for vehicle-to-vehicle scenarios. The outcome: 22 out of 30 recently tested cars earned good or acceptable ratings, showing clear progress.

Not everything is straightforward. A study in January 2025 revealed a twist: reflective clothing, meant to make pedestrians visible, can sometimes confuse AEB sensors, reducing detection accuracy. This highlights the real-world complexity behind safety tech.

Across the Atlantic, Euro NCAP published new frontal and side impact protocols in March 2025, along with a “Crash Protection — Definitions v1.0” document. By 2026, the weight of active safety in Europe’s star ratings is expected to grow significantly.

Recent model updates illustrate the balance between the two worlds. The 2025 Toyota Camry was assessed for rear passenger safety under the updated moderate overlap test. The 2025 Volkswagen Taos had to add rear seatbelt pretensioners and load limiters from January production onwards. Meanwhile, the 2025 Tesla Model Y proved the strength of its AEB, consistently avoiding crashes at speeds up to 37 mph.

The conclusion is clear: active and passive safety are not rivals but allies. One lowers the risk of a crash, the other boosts survival when prevention fails. As protocols become stricter, star ratings will increasingly reflect not only crash survival but also a car’s ability to see danger early and act in time.