The N-400 is the application for U.S. citizenship. Most green-card holders qualify after five years as a permanent resident (three if married to a U.S. citizen), and it is one of the most commonly self-filed immigration applications.
Naturalization is the process by which a lawful permanent resident (green-card holder) becomes a U.S. citizen, filed on Form N-400. Unlike most of the visa categories on this site, it is an application many people complete themselves.
Eligibility turns on a handful of concrete, checkable requirements — time as a permanent resident, physical presence, good moral character, and passing English and civics tests — most of which are numeric and set by regulation.
Yes — and here self-filing is the norm, not a technicality. You apply for your own naturalization on Form N-400; there is no petitioner and no sponsor. Many applicants file without an attorney, using the USCIS civics study materials to prepare for the test. The situations that genuinely warrant a lawyer first are specific: any arrest or criminal history, extended trips outside the U.S. that could break continuous residence, or gaps in taxes or (for some men) Selective Service registration.
The core eligibility requirements for the standard five-year track are set by 8 CFR § 316.2. A shorter three-year track exists for spouses of U.S. citizens under § 319.1 (see the FAQ). For the standard track you must show:
You must meet: all of the following (8 CFR § 316.2)
The N-400 has a filing fee; a reduced fee and a fee waiver are available for applicants who meet income thresholds. Fees change with USCIS fee rules — check the current N-400 fee and the fee-waiver eligibility on the linked USCIS schedule rather than any figure quoted elsewhere.
Processing runs from several months to over a year depending on the field office, and includes a biometrics appointment, the interview and tests, and the oath ceremony. You may file up to 90 days before completing the required residence period.
Ranges, not commitments — timing depends on your local field office and current USCIS workload.
N-400 is the strongest self-serve case on this site. The eligibility rules are numeric and checkable, the form is structured, and USCIS publishes the exact civics questions and English requirements. A straightforward applicant — clean record, no long absences, taxes in order — can reasonably file and prepare alone.
The value of self-serve tooling here is mostly organization and confidence: confirming your dates actually meet the continuous-residence and physical-presence math before you file, gathering the right documents, and preparing for the interview.
Talk to an attorney BEFORE filing if any of these apply: an arrest, citation, or conviction of any kind; trips abroad of six months or more; anything that could raise a good-moral-character or removability question; or unfiled taxes. In those situations an N-400 can surface an old problem, and it is far better to know that in advance. JustiGuide helps you check the requirements and organize the record; a licensed attorney handles the judgment calls.
The hard part of N-400 is structuring your evidence to the criteria above. Drop your documents and our team will organize them into a JustiGuide profile mapped to each requirement — so you (and any attorney you work with) start from an organized record, not a folder of PDFs.