Gaining U.S. citizenship can provide many opportunities for a resident of the United States. Among these are access to a U.S. passport, the right to vote in public elections, and protection from deportation.
However, becoming an American citizen requires a few steps, from establishing your eligibility to filing, fingerprinting, attending an interview, passing tests of your knowledge of English and of U.S. civics, and attending an oath ceremony.
WARNING: Regardless of when you're eligible, coronavirus closures will likely slow down the naturalization application process. In response to health risks presented by this global pandemic, U.S. Citizenship and Immigration Services (USCIS) has limited access to it offices to outside visitors. That means that, although it will accept your application. Expect long delays owing to the resulting backlog.
The first question is whether you have a U.S. green card (lawful permanent residence). With few exceptions, you must obtain a green card before you become eligible to apply for citizenship. So if you haven't yet reached this point, learn about your eligibility by reading Can You Get a U.S. Green Card?.
As a lawful permanent resident, you must meet additional requirements in order to be eligible for U.S. citizenship. These concern the length of time you've spent in the U.S. as a green card holder, your good moral character, your ability to pass a test in English, and on U.S. history and government, and more.
To check on whether you are eligible, see Who Is Eligible to Become a Naturalized U.S. Citizen?
Now would also be a good time to begin improving your English, if need be, and studying the possible questions that appear on the exam. As of December, 2020, there are 128 total questions the USCIS examiner can draw from, and you'll need to be able to answer 12 correctly in order to pass.
You might discover that you are not eligible to become a citizen just now. Perhaps you can't show good moral character because you committed a minor crime (though not a major enough one to make you deportable). Or perhaps you broke the continuity of your residence by spending too long outside the United States.
It might be that simply waiting longer will make you eligible for citizenship, or you might need to take other steps to make you eligible. In the worst case, it might be that you were granted lawful permanent residence when you shouldn't have been, in which case applying for citizenship could risk having USCIS discover this an take steps to remove you. Consult an immigration attorney for a full analysis.
See On What Grounds Can I Be Denied U.S. Citizenship? for common reasons your citizenship would be refused.
Once you have established your eligibility, you need to file some paperwork with U.S. Citizenship and Immigration Services (USCIS). The N-400 is the form to get the process started. As of late 2020, it costs $640 to file the application for naturalization, plus an $85 biometrics (fingerprinting) fee; but USCIS has proposed a fee hike.
You will also need to attach a copy of your green card to you application, and any documents showing that you warrant an exception or the like.
Soon after your application has been accepted, you will be mailed a date for your biometrics appointment.
See our tips for filing the N-400 to find out what to expect.
In order to process your application, a background check will have to be performed. You will be given a date and address to a local office where you will be fingerprinted. Your fingerprints will be run through the FBI and related databases for a background check.
Some weeks after your biometrics appointment, you should receive an appointment date and address for an interview with a UCSIC officer.
During this interview, the officer will go through your N-400 and confirm your answers to all the questions and your basic eligibility. The officer will also review your immigration file, looking for past issues. The officer will then test your knowledge of English and of U.S. civics.
To help prepare, read Preparing for the Naturalization Interview.
If you are approved at (or soon after) your USCIS interview, congratulations, but you are not a citizen quite yet. First off, you must maintain your eligibility. If, for example, you were to be arrested for a serious crime before the oath ceremony, you might lose eligibility.
You will be called in for a large public ceremony, at which you and others will be given the oath by which you swear loyalty to the United States. Then you will be given a certificate of naturalization, showing that you are a U.S. citizen.
You don't necessarily need to hire a lawyer to apply for U.S. citizenship, unless you have some troublesome items in your background. If you're ready to take on the task yourself, see Becoming a U.S. Citizen, A Guide to the Law, Exam & Interview, by Ilona Bray (Nolo).