The NFL's current rules require that a team's home uniforms must be "either white or official team colour" throughout the season, "and visiting clubs must wear the opposite".

The NFL rulebook states that the home team gets to decide which jersey it will wear, and because most home teams choose to wear darker uniforms with their primary team colors on it at home, it is standard for the away teams to wear white or gray on the road so that the two teams can be easily distinguished by the players, referees, and fans.