Every state except New Hampshire has some form of seatbelt law. While most state laws only require seatbelts in the driver and passenger seats, 17 states (and D.C.) require all passengers to be buckled in.
In D.C. and Maryland, seatbelt laws are considered “primary”, meaning that police officers can pull over drivers simply for not wearing the belt. In Virginia, on the other hand, failure to wear a seatbelt is a secondary offense, only punishable if you are stopped for some other violation.
Maryland and Virginia require drivers and the person in the front passenger seat to wear a seatbelt, subject to a $25 fine.
The District requires all passengers to wear seatbelts, punishable by a $50 fine.