The USA Marathon Championships is the annual national championships for marathon running in the United States. The race serves as a way of designating the American national champion for the marathon. The men's race was first contested in 1925 and a women's race was added to the program in 1974.
Since 1968, in years which the Summer Olympics are held the event serves as a way of selecting the athletes who will represent the United States at the Olympic Games, with the top three eligible finishers selected to be on the Olympic team and the fourth and fifth eligible finishers being designated as alternates. During these years, the race is more commonly referred to as the U.S. Olympic Marathon Trials and it is much more competitive.