How do I become a U.S. citizen?

A person may become a U.S. citizen (1) by birth or (2) through naturalization. Naturalization is the way immigrants become citizens of the United States. In most cases, you must be an immigrant (permanent resident) with continuous residence in the U.S. for a number of years before you may apply for naturalization. If you were born in the United States (including, in most cases, Puerto Rico, Guam, and the U.S. Virgin Islands), you are a U.S. citizen at birth (unless you were born to a foreign diplomat). Your birth certificate is proof of your citizenship. If you were born abroad to a U.S. citizen parent, you may also be a citizen at birth.