By the time you reach the naturalization interview you have already done the hard part, which was being eligible for long enough. The interview is a check on the file, a test, and a conversation, in that order of importance.
Which civics test you take
There are two versions in circulation, and the one you take depends on when you filed rather than on when you are interviewed. Applicants who filed before 20 October 2025 take the 2008 test. Applicants who filed on or after that date take the 2025 version, which is based on the 2020 test with changes to how it is administered. Study the list that matches your filing date, not the first one you found.
Applicants aged 65 or older who have been permanent residents for at least twenty years study a shorter list of questions and may take the test in their own language.
The application review
The officer goes through your N-400 with you, line by line, under oath. Addresses, employers, trips outside the country, marriages, children, arrests. If something has changed since you filed, say so at the interview. If something was wrong when you filed, say that too, because the officer usually has the underlying record already.
Trips abroad get particular attention, because long absences can break the continuous residence the application depends on. So do arrests, including old ones, including ones that were dismissed, including ones you were told would not matter.
Good moral character
The statute asks whether you have been a person of good moral character during the statutory period, which is five years for most applicants and three for those married to a U.S. citizen. In practice that means unpaid taxes, missed child support, unreported arrests, and anything involving false claims to citizenship or voting come up here, and they can matter well beyond the period on paper.
English, reading, writing
Reading and writing one sentence correctly out of up to three attempts, and speaking well enough to answer the officer's questions about your own application. Most people who can hold the interview conversation pass this part without noticing it happened.
If something goes wrong
A failed test on the first attempt is normally rescheduled rather than denied. A denial can be appealed. The worse outcome is an interview where an old problem surfaces that nobody prepared for, which is the argument for having your history reviewed before you file rather than after the officer opens the folder.