Form N-400: Application for Naturalization
The application to become a U.S. citizen through naturalization.
General filing.
Add this to the fee calculator → · Official USCIS calculator
Verified from USCIS Form G-1055, edition 05/29/26. Fees change frequently — confirm before filing.
Who files Form N-400?
Green card holders who meet the residence, physical-presence, and good-moral-character requirements (generally after 5 years, or 3 years if married to a U.S. citizen).
Most common N-400 mistakes that cause rejections
USCIS rejects or issues a Request for Evidence on filings every day for small, fixable errors. For N-400, the ones we see most often are:
- Miscalculating continuous residence or physical presence, or omitting trips outside the U.S.
- Filing under the wrong basis (3-year vs. 5-year rule).
- Incomplete disclosure of tax, selective-service, or criminal history questions.
- Leaving required fields blank instead of answering every item.
Check your N-400 before you file
Upload your completed N-400 and FormGuard reviews it for these exact rejection triggers in about a minute — for $39, one time. Your file is analyzed and never stored.
Check my N-400 for errors — $39 →How to file Form N-400 without getting rejected
- Use the current edition. USCIS rejects outdated editions — check the date printed at the bottom of the form against uscis.gov.
- Answer every field. Write “N/A” or “None” instead of leaving anything blank — blanks are a leading rejection cause.
- Be consistent. Your name, A-Number, and dates must match exactly across every form and supporting document.
- Sign and date correctly. An unsigned or wrongly-signed form is rejected outright.
- Translate foreign documents. Include a complete certified English translation of anything not in English.
- Pay the exact fee. Use the fee calculator and confirm on uscis.gov — the wrong amount gets the package returned.
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Form N-400 — frequently asked questions
How much is the Form N-400 filing fee?
The USCIS filing fee for N-400 is $710 online / $760 paper (General filing), per the current G-1055 schedule (edition 05/29/26). Always confirm at the official USCIS fee calculator before filing.
Can I file Form N-400 online?
Many applicants can file N-400 through a USCIS online account, which is $50 cheaper than paper filing. Check uscis.gov for current online-filing availability for your situation.
What happens if my N-400 is rejected?
USCIS returns rejected forms without processing them, and filing fees are generally non-refundable — so you lose time and may have to pay again. Most rejections come from small, avoidable errors, which is why a pre-filing review is worth it.
FormGuard is a private, independent service and is not affiliated with, endorsed by, or connected to U.S. Citizenship and Immigration Services (USCIS) or any U.S. government agency. FormGuard is not a law firm and does not provide legal advice. This page provides general information only; fees and form requirements come from published USCIS sources and change frequently — always verify current details at the official government website, uscis.gov, and consult a licensed immigration attorney for complex matters.