Naturalization is the process by which U.S. citizenship is granted to a lawful permanent resident after meeting the requirements established by Congress.

Once a permanent resident becomes a US Citizen, the person may vote in a federal election, stay indefinitely outside the United States without consequence, and generally can never lose their status.

To become a United States Citizen, an immigrant must be a permanent resident for at least five years (3 if residency obtained via marriage to a US Citizen), submit a form N-400, and pass an interview.

An applicant must also take an oath of allegiance to the United States of America.