If you’re researching new cars, safety ratings and crash tests are likely to factor into your decision making. There are two well-known sources of crash test ratings:
Both provide valuable information but their testing and scoring methods are different and they are funded differently, one being a government agency, and the other not.
NHTSA 5-Star Rating System
NHTSA was officially established by the Highway Safety Act of 1970. Its mission is to “save lives, prevent injuries and reduce economic costs due to road traffic crashes, through education, research, safety standards and enforcement activity.” So minimizing deaths and injuries is its sole motivation.
The agency's New Car Assessment Program (NCAP), introduced in 1993, ranks vehicles using a 5-Star Safety Rating system with 5 being the best. You’ll find NHTSA ratings (when available) on vehicle Monroney stickers. The NHTSA currently conducts four crash tests: front impact, side barrier, side pole, and rollover resistance.
The NHTSA is currently proposing to add driver-assistance safety technology evaluation to testing criteria along with a number of other updates below:
The NHTSA also offers 5-Star Car Seat Ease-of-Use Ratings.
IIHS Top Safety Pick+
The Insurance Institute for Highway Safety (IIHS) refers to itself as "an independent, nonprofit scientific and educational organization dedicated to reducing deaths, injuries and property damage from motor vehicle crashes through research and evaluation and through education of consumers, policymakers and safety professionals." The IIHS was founded in 1959 by three major insurance associations representing 80 percent of the U.S. auto insurance market. For a lengthy list of its supporting member groups click here.
The IIHS conducts more tests and incorporates more driver-assistance technology than the NHTSA currently does. The IIHS currently conducts 6 crash tests: driver-side small overlap front, passenger-side small overlap front, moderate overlap front, original side, roof strength and head restraints/seats. It rates vehicle crashworthiness and headlights on four levels; Good, Acceptable, Marginal or Poor. Crash Prevention is rated as Superior, Advanced or Basic.
In October 2021, the IIHS announced a new, updated, tougher side crash test designed to address higher-speed crashes. Additionally, the Institute also tests headlights and front crash prevention systems (vehicle to vehicle and vehicle to pedestrian) and LATCH ease of use.
High performers are awarded a Top Safety Pick or a Top Safety Pick + rating, the latter being the highest award.
When you’re buying a new car, look at both sites. It doesn’t hurt to get two points of views. I personally prefer NHTSA, since IIHs represents the insurance industry. That said, IIHS does some good work along with NHTSA so we’d suggest checking out both crash test ratings.