Reviewed July 31, 2026

File Form N-400 for naturalization

A correct N-400 filing starts with eligibility and timing, not with filling the first field. Review the full history and current USCIS instructions before submission.

Use the official form page on the filing date

USCIS can change the accepted form edition, fee, filing address, and online workflow. Verify each item immediately before submitting rather than relying on a saved copy or third-party checklist.

1. Confirm the legal basis

Identify whether you are filing under the regular five-year rule, the three-year rule for certain spouses of U.S. citizens, a military provision, or another special category. The selected basis controls the statutory period and evidence.

2. Calculate the earliest filing date

Applicants under the common five-year or three-year continuous-residence routes may be able to file up to 90 calendar days before completing that residence period. Use the USCIS Early Filing Calculator. The early-filing rule does not waive age, local residence, physical presence, marriage, good-moral-character, or other requirements.

3. Build an accurate timeline

  • Addresses during the required period.
  • Employment and schools.
  • Every trip outside the United States, with departure and return dates.
  • Marriages, divorces, children, and household information requested by the form.
  • Tax filing history and any overdue tax arrangements.
  • Selective Service information when applicable.
  • Arrests, charges, citations, court outcomes, probation, and other conduct requested in the form.

4. Choose online or paper filing

  • Online: use a USCIS online account, complete the guided form, upload evidence, pay the applicable fee, and save the final submission.
  • Paper: use the accepted edition, complete all applicable questions, sign the form, attach copies and payment, and send it to the current USCIS filing location with tracking.
  • Fee relief: review current reduced-fee and fee-waiver rules. The filing method and supporting evidence may change when requesting fee relief.

5. Attach evidence that matches the basis

All applicants generally provide a copy of both sides of the Permanent Resident Card unless the instructions provide another rule. Additional evidence can include marriage and spouse-citizenship records, tax transcripts, proof of marital union, court dispositions, Selective Service documentation, evidence about long trips, legal name-change records, or certified English translations.

6. Review, sign, and submit

Check names, A-Number, dates, travel totals, answers to eligibility questions, translations, evidence, fee method, and signature. Keep a complete copy of the exact filing and delivery confirmation.

7. Respond to USCIS

Read every receipt, biometrics notice, interview notice, request for evidence, and decision. Update your address through the USCIS process if you move. Bring the requested originals and identification to the interview.

8. Prepare for the interview and tests

The officer reviews the application and tests English and civics unless an exception applies. Applicants filing on or after October 20, 2025 generally use the 2025 civics test; earlier filers generally use the 2008 test. Study from the USCIS materials for your test version.

9. Complete the oath ceremony

If approved, follow the ceremony notice, answer the Form N-445 questions truthfully, surrender the Permanent Resident Card when instructed, and take the Oath of Allegiance. Review the Certificate of Naturalization immediately for errors before leaving the ceremony.

Official sources

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