New Car Safety Ratings Explained

By Keith Griffin

No one ever plans to be in a car accident, but if one happens, we want to be safe. In fact, a 2012 survey by the Consumer Reports National Research Center found that 65 percent of car buyers said safety was the most important thing to them when deciding which car to buy. There’s just one problem: How do you tell if a car is safe?

When researching a new or used car online, there are two important safety ratings to look for: the National Highway Traffic Safety Administration’s star ratings and the Insurance Institute for Highway Safety’s top picks. While they seem easy to comprehend, they both present complex information that can help you decide which car, truck or SUV is right for you.

Though the 2015 Acura TLX shown here looks wrecked, the space around the driver is preserved, which means the car offers good crash protection. (Insurance Institute for Highway Safety)

The National Highway Traffic Safety Administration, commonly known as NHTSA, is part of the U.S. Department of Transportation. It pioneered automobile safety ratings globally in 1978, says Gordon Trowbridge, NHTSA’s director of communications. Since then, the European Union and countries around the world have created new car assessment programs, sometimes called by the acronym NCAP.

Trowbridge says NHTSA’s NCAP meets different goals. The first is to provide accurate, reliable information to consumers about the crash protection offered by new or used vehicles they are considering buying. In particular, he says, it allows car shoppers to evaluate the strengths and weaknesses of various vehicles when it comes to crash worthiness.

David Zuby, executive vice president and chief research officer for the Insurance Institute for Highway Safety, says there’s a secondary goal to his organization’s testing (and one Trowbridge says NHTSA also focuses on): getting manufacturers to fix safety flaws identified by the testing. “We know that automakers are paying attention to the tests. They may not score good results when we first initiate a test but we see them make changes that lead to better scores,” Zuby says.

When it comes to rating the cars, NHTSA uses a straightforward star rating system with five stars being the highest rating. You can see the full results at SaferCar.gov. However, NHTSA ratings are split into ratings for vehicles from 2010 and older vehicles, and vehicles from 2011 and newer. What that means, Trowbridge says, is consumers can’t make a direct comparison between 2011 and newer models and those made from 1990 to 2010. Since 2011, NHTSA ratings have included an overall score summarizing the categories of frontal crash, side crash and rollover risk. Trowbridge says the rollover risk test is unique to NHTSA.

IIHS conducts testing that measures how a vehicle responds to small and moderate overlap frontal crashes, side impact crashes, how its roof strength holds up during a simulated rollover and how its seats respond in a rear-end collision. The IIHS Top Safety Pick designation is for cars that have ratings of Good, the highest rating possible, in all categories. However, an Acceptable rating is sufficient for the small overlap front test. According to the IIHS website, the small overlap front test, established in November 2012, measures the simulated impact of a car’s front corner striking another vehicle or something like a utility pole or tree. The IIHS didn’t want to negate Top Safety Picks awarded before 2012, which is why Acceptable ratings are allowed on small overlap front tests.