US Naturalization Requirements: Who Can Apply for Citizenship
In this guide
Quick answer: The main naturalization requirements are being at least 18, holding a green card for at least five years (three if you are married to a US citizen and meet the marriage rules), continuous residence, physical presence for at least half of that time, good moral character, basic English, civics knowledge and the Oath of Allegiance. You apply with Form N-400.
Becoming a US citizen is the last step of many immigration journeys, and it is also where small details cause the most rejections. USCIS separates two ideas that people often mix up: continuous residence and physical presence. You need both. This guide walks through the rules as USCIS states them, so you can check where you stand before you file.
What are the naturalization requirements for a five-year green card holder?
USCIS says the most common path is being a lawful permanent resident for at least five years. To be eligible on that basis, you must:
- Be at least 18 when you submit Form N-400.
- Show that you have been a lawful permanent resident for at least five years.
- Show continuous residence in the United States for at least five years immediately before filing.
- Show you were physically present in the United States for at least 30 months out of those five years.
- Have lived for at least three months in the state or USCIS district where you file.
- Show good moral character for at least five years before filing.
- Show attachment to the principles of the US Constitution.
- Read, write and speak basic English.
- Know the basics of US history and government (civics).
- Take the Oath of Allegiance.
What if you are married to a US citizen?
USCIS describes a shorter path under section 319(a). You must have been a permanent resident for at least three years, and have lived in marital union with your US citizen spouse for those three years and while USCIS decides your case. You also need three years of continuous residence, at least 18 months of physical presence in those three years, and the same English, civics and moral character requirements.
| Requirement | Standard path | Married to a US citizen |
|---|---|---|
| Time as a permanent resident | 5 years | 3 years |
| Continuous residence | 5 years | 3 years |
| Physical presence | 30 months | 18 months |
| Marital union | Not required | 3 years with your citizen spouse |
| Minimum age at filing | 18 | 18 |
USCIS also describes a separate rule, section 319(b), for spouses of certain US citizens employed abroad, with different residence and presence requirements.
Can you live in two countries and still qualify?
This is the question USCIS answers directly in its commonly asked questions. To qualify, you must have continuously resided in the United States, which means living here, not in another country. Travel is allowed, but USCIS says a trip longer than 180 days may lead it to decide you have not continuously resided in the US. It also looks at how often you travel: you must spend at least half your time in the US, and many short trips that add up to more than half your time abroad can also make you ineligible. If you plan long trips, read about the reentry permit for green card holders.
What are the steps from application to oath?
- Check you are not already a citizen, for example by birth or through a parent.
- Check you are eligible using the USCIS eligibility tool.
- Prepare Form N-400. It can be filed online. If you live outside the US, you need two passport-style photos.
- Submit Form N-400 and pay the fees. USCIS sends a receipt notice.
- Attend biometrics if USCIS asks for them.
- Complete the interview.
- Receive a decision: granted, continued or denied.
- Receive the oath notice, and in some cases take the oath the same day.
- Take the Oath of Allegiance. USCIS says you are not a citizen until you do.
At the ceremony you turn in your green card and receive your Certificate of Naturalization. Check it for errors before you leave. The test itself is covered in our guide to the US naturalization test.
Common mistakes
- Counting days wrongly. Continuous residence and physical presence are separate tests.
- Staying abroad too long on a green card. A trip over 180 days can raise questions.
- Assuming a passed test means approval. You must meet every requirement, including speaking English at the interview.
- Not mentioning a name change. You must give USCIS the document that changed your name.
FAQ
Do I need a lawyer to apply?
No. USCIS says you can file yourself, including online. If you want help, only attorneys and accredited representatives can give legal advice or communicate with USCIS about your case.
Can I change my name when I naturalize?
Yes. USCIS says you can request a name change, but you must then take the oath at a judicial ceremony because USCIS cannot change names itself.
Do I have to bring original documents to the interview?
USCIS says yes. Follow the Form N-400 instructions for what to bring.
What if I fail part of the test?
You get two attempts. USCIS retests you on the part you failed between 60 and 90 days after the first interview.
Key takeaways
- Standard path: five years as a permanent resident, 30 months present in the US.
- Married to a US citizen: three years, with 18 months present and marital union throughout.
- Trips over 180 days can break continuous residence.
- You become a citizen only when you take the Oath of Allegiance.
Related guides
- US naturalization test: civics and English
- How to renew a green card
- How to apply for Canadian citizenship
- British citizenship routes explained
This page is general information, not legal or immigration advice. Confirm every requirement on the official USCIS site. Last updated: October 2026.
Sources
USCIS: I am a Lawful Permanent Resident of 5 Years; USCIS: I am Married to a U.S. Citizen; USCIS: 10 Steps to Naturalization; USCIS: Commonly Asked Questions About the Naturalization Process.