Naturalization is the process by which a lawful permanent resident (a green card holder) becomes a U.S. citizen. The application is Form N-400. Most applicants qualify on one of two timelines.
The two timelines
- Five years as a permanent resident, for most applicants.
- Three years as a permanent resident for people married to and living with a U.S. citizen during that time, when the spouse has been a citizen for the whole period.
U.S. Citizenship and Immigration Services (USCIS) accepts applications up to 90 days before the applicant reaches the required period.
Residence and presence
Two separate tests apply, and they are often confused:
- Continuous residence asks whether the person kept their home in the United States. Long trips abroad can break it. A trip of six months or more raises questions, and a trip of one year or more generally breaks continuous residence.
- Physical presence counts days actually spent in the country. Applicants need at least half of the required period.
Good moral character
Officers review the applicant's conduct during the eligibility period, including taxes, child support and any arrests. Every arrest must be disclosed, even one that led to no charge. Certified court records help an officer assess it.
The tests
The interview includes an English test (reading, writing and speaking) and a civics test on U.S. history and government. Some older long-term residents and applicants with qualifying medical conditions may receive exceptions.
The fee
The fee schedule in effect on 1 October 2026 lists $760 for a paper N-400 and $710 online.
When to get advice first
A short review before filing is sensible for anyone with long trips abroad, any arrest or citation, unfiled tax returns, or doubts about how they obtained their green card. Problems found at the interview are harder to fix than problems found before filing.