There is no federal seat belt law; such laws are left to the individual states. The U.S. Department of Transportation, through NHTSA, offers grant programs to states; in 2002, 48 states, the District of Columbia, and Puerto Rico shared a $44.4 million grant (Maine and Wyoming declined to take any grant money). Safety and public awareness campaigns are also conducted by NHTSA. Probably the best known is the series of print and broadcast advertisements that feature Vince and Larry, the crash test dummies.

In 1998, Congress passed the Transportation Equity Act for the 21st Century (TEA-21), which includes grant money for states to initiate new seat belt laws, traffic enforcement programs, and child passenger protection and training activities.