The 32-team National Football League (NFL) is currently the only major American football league in the United States. There have been numerous attempts over the past several decades to create a second major or high-level professional league, most of which failed within a few years or, in the cases of the All-America Football Conference and 1960s American Football League, merged with the NFL. The National Football League has the highest revenue and average attendance of any sports league in the world.

The NFL has not operated any developmental minor leagues since the folding of the NFL Europe League in 2007. There are some "independent" leagues operating in the US, but they are not overseen by the NFL and the teams has no affiliation to NFL franchises.