The United States of America has 50 states. A lot of people think it has 51 or 52 because they mentally add places like Washington, D.C. and Puerto Rico, but those are not states – D.C. is a federal district and Puerto Rico is a U.S. territory. Alaska and Hawaii were the last two states admitted, both in 1959, bringing the total to 50, and no new states have been added since then.