The American Paint Horse's combination of color and conformation has made the American Paint Horse Association (APHA) the second-largest breed registry in the United States based on the number of horses registered annually. While the colorful coat pattern is essential to the identity of the breed, American Paint Horses have strict bloodline requirements and a distinctive stock-horse body type. To be eligible for registry at least one parent must be a registered American Paint Horse.

Each Paint Horse has a particular combination of white and any color of the equine spectrum: black, bay, brown, chestnut, dun, grullo, sorrel, palomino, buckskin, gray or roan. Markings can be any shape or size, and located virtually anywhere on the Paint's body.