USCIS Forms N-400
Naturalization
Become a US citizen. Requirements, the civics test, and how we prepare you for the interview.
N-400, At a glance
Rev 2026- Who files
- Permanent resident
- Filing fee
- $710 online · $760 paper
- Typical timeline
- 8–14 months
- Filed with
- USCIS
USCIS updates fees and processing times without notice. Confirm the current figures on USCIS.gov before you file, or ask us and we'll check them with you.
Processing times vary by form, category and field office. Look up the current time for your own case with the USCIS processing times tool.
Who qualifies
Most applicants qualify after five years as a permanent resident, or three years if they have been married to and living with a US citizen for those three years. In either case USCIS also looks for continuous residence for the whole period, physical presence in the United States for at least half of it, three months in the state or district where you file, good moral character, and the ability to read, write and speak basic English and pass the civics test, unless an age-based exception applies. You can file up to 90 days before the anniversary that completes your period. A single trip abroad of six months or more can break continuous residence, and a trip of a year or more is presumed to.
What to gather before you file
- 01Your permanent resident card, front and back, and every passport you have held since becoming a resident
- 02A complete list of trips outside the United States for the whole period, with departure and return dates
- 03For the three-year rule: your marriage certificate, proof your spouse is a US citizen, and evidence you live together
- 04Decrees ending every prior marriage, yours and your spouse's
- 05Tax transcripts for the period, and proof of a payment plan if any tax is owed
- 06Proof of Selective Service registration, or a status letter, for men who lived in the US between 18 and 26
- 07Certified court dispositions for any arrest, citation or charge, even if dismissed or expunged
- 08Proof of child support payments, if you have children who do not live with you
How the process runs
- 01
File
We complete the N-400 from your answers, check every trip and every address against your records, and file online or by mail. USCIS issues a receipt notice.
- 02
Biometrics
Fingerprints and a photograph at an application support center, or reused from an earlier filing when USCIS already has them.
- 03
Interview and tests
An officer goes through your application under oath, tests your English in speaking, reading and writing, and asks the civics questions. Which civics test you take depends on the date you filed. Our study-plan article explains the versions.
- 04
Oath ceremony
After approval you are scheduled for the oath of allegiance. You become a citizen at the ceremony, hand in your green card, and receive the certificate of naturalization.
Common mistakes we catch
A trip of more than six months with no explanation. Filing before the 90-day window opens, which gets the application denied outright. A year of taxes filed as a nonresident, or not filed at all. A citation or arrest left off because it seemed minor. Travel dates that do not match what the border records show. Selective Service never registered and never explained. None of these is necessarily fatal, but every one of them has to be addressed before the interview rather than discovered in it.