Below is a list of National Amateur Boxing Welterweight Champions, also known as United States Amateur Champions, along with the state or region which they represented. The United States National Boxing Championships bestow the title of United States Amateur Champion on amateur boxers for winning the annual national amateur boxing tournament organized by USA Boxing, the national governing body for Olympic boxing and is the United States' member organization of the International Amateur Boxing Association (AIBA). It is one of four premier amateur boxing tournaments, the others being the National Golden Gloves Tournament, which crowns its own amateur light welterweight champion, the Police Athletic League Tournament, and the United States Armed Forces Tournament, all sending champions to the US Olympic Trials. It was contested at 139lbs until 2002 when it was changed to 141lbs.