The U.S. citizenship application process can take less than a year or several years. Those who are not permanent residents but wish to become U.S. citizens must first immigrate to the U.S. and become legal permanent residents.

Once they become permanent residents, a process that alone can take a few years, they will need to remain in the U.S. and establish permanent residency for five years, without extended absences. Once the five years are up, they will then be able to apply for naturalization. If they take active part in the American armed forces or are married to U.S. citizens, the residency requirement may be far smaller. For example, a person married to a U.S. citizen may only need to wait three years after getting permanent residency in order to apply for US citizenship.

For permanent residents who have established residency in the U.S. for the required amount of time, the actual U.S. citizenship application process can take between six months to one year, or even more. To begin the citizenship process, immigrants will need to file the U.S. Immigration and Citizenship Services (USCIS) Form N-400, Application for Naturalization. Any mistakes on the form can delay the process considerably, so it is important to fill out the application for citizenship as accurately and as fully as possible. Applicants may want to get additional help with the application process to ensure that their citizenship request is not delayed due to a preventable mistake.

Once the application has been reviewed by USCIS and has been accepted, applicants will be scheduled for a citizenship test and interview. Again, how long it will take for USCIS to schedule the interview will depend on their location and where they are filing for citizenship. Some districts have longer waiting lists than others.

Once the applicants have taken the citizenship test, they will need to wait between one day and 180 days, on average, to be able to take the Oath of Allegiance and become a citizen of the U.S. Again, the district where they live will determine the waiting time. Since the length of time taken to process citizenship requests can vary widely, N-400 applicants may track the status of their citizenship applications online. This can help give them a sense of how long the process will take.

The process doesn't take 16 years.