USCIS Form N-400: Complete Guide to the Application for Naturalization

USCIS Form N-400, the Application for Naturalization, is the official government form you file to become a United States citizen. It collects biographical information, your immigration history, and your eligibility basis — whether through five years of lawful permanent residence, three years as the spouse of a US citizen, or qualifying military service. You can file online through your myUSCIS account or submit a paper application by mail to the appropriate USCIS lockbox facility.

The form itself is 21 pages and contains 18 parts. Most applicants find Part 12 (Additional Information About You) and the Good Moral Character section the most detailed, since they ask about criminal history, tax filings, memberships, and any prior removal proceedings. Accuracy matters — even minor inconsistencies between your N-400 answers and your A-File records can trigger requests for evidence or delay your interview.

Filing fees are $760 for paper applications and $710 for online filings as of 2026. A biometric services fee of $85 is also required for most applicants (though it may be combined with the main filing fee depending on your age and filing method). Fee waivers are available if your household income is at or below 150% of the Federal Poverty Guidelines, or if you receive certain means-tested public benefits.

Before you start filling out the N-400 application, confirm your eligibility. You must have been a lawful permanent resident for the required continuous residence period, maintained physical presence in the US for at least half of that period, demonstrate continuous residence in your state or USCIS district for three months before filing, and be able to show good moral character throughout the statutory period.

Understanding what USCIS looks for in your application before you file makes the process far less stressful. USCIS officers are not trying to deny applications — they are verifying that the information you provide is accurate and that you meet the statutory requirements. The vast majority of applicants who meet the eligibility criteria and file accurately receive approval. Your job is to give the officer everything they need to reach that conclusion quickly and confidently.

Many applicants benefit from reviewing similar N-400 applications that USCIS has published in redacted form through FOIA releases, available on various immigration law websites. Seeing how other applicants handled complex travel histories, prior arrests, or other complications helps you frame your own answers accurately. If your situation involves anything outside the straightforward five-year path, take extra time with those sections and consider a consultation with an immigration attorney before finalizing your form.

Once you're confident in your eligibility and have gathered your documents, the filing process itself is straightforward. Most applicants complete the form in two to three sittings, reviewing each section carefully before moving to the next. Give yourself plenty of time — rushing through the form increases the chance of errors that require correction later.

Completing the N-400 accurately requires reading the official N-400 instructions thoroughly before touching the form. USCIS updates the form periodically — always download the current version from uscis.gov and check the edition date in the lower-left corner of the form. Using an outdated version is the most common reason applications get rejected at the lockbox without review.

Part 2 collects your personal information including all names you have ever used — maiden names, nicknames, and aliases all belong here. Part 3 asks for your immigration history: when you became a permanent resident, your A-Number, and the class of admission on your green card. Match these exactly to your green card and any prior immigration documents you received.

The Good Moral Character section (Parts 11 and 12) asks about arrests, citations, criminal charges, and a range of conduct-based questions. Answer every question honestly, even if you received a dismissal or expungement. USCIS has access to FBI records and may have information in your A-File you're not aware of. An honest disclosure is almost always better than a discovered omission.

Part 14 requires your signature under penalty of perjury. If you need an interpreter, they must also sign. If you used a preparer, their information goes in Part 15. Do not sign until you have reviewed all parts — corrections after submission require an amended form or an explanation at interview.

One frequently overlooked step is gathering all your travel documentation. Print a complete list of every trip you have taken outside the US during the statutory period, including short weekend trips to Canada or Mexico. USCIS asks about all absences regardless of duration — the officer at your interview may have a travel history from your passport scans at ports of entry and will notice if your N-400 list is incomplete. For each trip, record the destination, departure date, return date, and purpose of travel.

If any trip lasted 6 months or more, prepare additional evidence showing you maintained your ties to the US during that absence: rental agreements or mortgage statements, employment records, US bank account activity, and letters from family or employers. A single extended trip does not automatically disrupt your continuous residence, but USCIS will scrutinize it closely and you need contemporaneous evidence that you intended to return.

Supporting documents should be organized in exactly the order they appear on the USCIS checklist, with each document clearly labeled. Use numbered tabs or a simple cover sheet to help the USCIS officer navigate your package. When submitting copies, make sure every copy is clean, readable, and shows the complete document without cropping. Poor-quality photocopies are a preventable source of Requests for Evidence.

Certified translations are required for any foreign-language document. A certified translator must include a signed statement that they are competent to translate and that the translation is accurate. Most translation services provide this automatically — confirm it is included before using any translation firm. USCIS returns packages that include untranslated foreign-language documents, which adds weeks to your timeline. Certified translation costs typically run $50–100 per page depending on the language and service provider, so budget for this early in your preparation.

After USCIS accepts your N-400, the processing timeline includes several discrete stages. Your biometrics appointment typically comes 3–6 weeks after your receipt notice. At a USCIS Application Support Center, a technician collects your fingerprints, photograph, and signature, which are used for FBI background check processing. Bring your appointment notice and a valid government-issued photo ID to the appointment.

The interview notice follows FBI background check clearance, which usually takes 2–4 months. Your interview is conducted at your local USCIS field office. You must bring your appointment notice, a valid photo ID, your green card, your passport, and all original documents you submitted copies of with your application. The officer will review your N-400 with you line by line and administer the English reading, writing, and speaking tests along with the civics exam.

Most applicants receive a decision — approval, continuation, or denial — at the end of their interview. If approved, you may take the Oath of Allegiance at a ceremony the same day in some offices, or you receive a notice scheduling a future ceremony. Naturalization ceremonies are held at USCIS offices, federal courthouses, and sometimes at civic events and sporting events, depending on your district.

If your application is continued (not denied), you receive a written notice specifying what additional evidence or action is needed. Respond completely and promptly — continued cases can be re-scheduled for a second interview or approved on the record depending on what was needed.

Between your biometrics appointment and your interview, there is usually a quiet period of several months when your case is actively in queue. Use this time productively: study the 100 civics questions thoroughly, practice the English reading and writing vocabulary lists, and gather any additional documents you may need. If your circumstances change — a new criminal matter, an extended trip, a divorce or new marriage — file an update immediately using the USCIS Contact Center or by mailing a letter to your field office.

Expedite requests are available in limited circumstances: military deployment, severe financial loss, extreme humanitarian situations, Department of Defense interest, or USCIS error causing a delay. To request expedited processing, submit your request through your myUSCIS account with supporting evidence. USCIS evaluates expedite requests case by case and grants them sparingly, so provide the strongest documentation you have for your specific circumstance.

The civics test covers US history and government from a pool of 100 official questions. An officer asks you up to 10 questions, and you must answer at least 6 correctly. The 100 questions are publicly available on the USCIS website — every applicant should study them before the interview. Practice answering the questions aloud, not just reading them, since the officer asks verbally and expects a verbal answer without referring to notes.

The English test has three components: reading (read one sentence aloud correctly from up to 3 sentences given), writing (write one sentence correctly from up to 3 dictated sentences), and speaking (demonstrated throughout the interview via your responses). The reading and writing sentences come from a vocabulary list published by USCIS — study that list so you recognize every word in context.

Exemptions from the English requirement apply to applicants 50 years or older with at least 20 years of LPR status (50/20 rule), or 55 years or older with at least 15 years of LPR status (55/15 rule). These applicants may take the civics test in their native language with an interpreter. A medical disability exception applies if you have a medically determinable physical or developmental disability or mental impairment — file Form N-648 completed by a licensed medical professional before your interview.

At the civics test, the officer will ask questions from the official list of 100. Some questions have multiple acceptable answers — for example, "What are two rights in the Declaration of Independence?" accepts any two from the list of provided options. Practice answering questions with exactly the phrasing shown in the USCIS study materials, since some officers are strict about phrasing while others accept paraphrased answers that clearly demonstrate understanding.

After the interview, if approved, you may take the Oath of Allegiance at a ceremony the same day in some districts. Bring your green card to the ceremony — it will be collected and you will receive your Certificate of Naturalization in exchange. After the ceremony, apply for a US passport as soon as possible. Your Certificate of Naturalization is your most important identity document — keep the original in a secure location and obtain certified copies for important transactions.

Review N-400 processing time data for your field office before filing — if your office is backlogged, filing earlier gives you more cushion before your green card expires or you need to plan around travel. File as soon as you become eligible (90 days before your continuous residence period completes) unless your travel history or pending matters make early filing risky.

Organize all your documents into a clear order before mailing or uploading. Number your pages if submitting by mail, and include a cover sheet listing every document you are including. USCIS officers process thousands of applications — a well-organized package reduces the chance of a document being overlooked or a request for evidence being issued for something you actually submitted.

If your situation involves complexity — past criminal charges, extensive travel, tax issues, or a prior visa violation — consult an immigration attorney before filing. Many immigration legal aid organizations provide free or reduced-cost consultations for applicants who cannot afford private counsel. The cost of professional guidance is usually far less than the cost of a delay, denial, or Request for Evidence that requires corrective action.

Study the N-400 form PDF version alongside your completed draft to do a final side-by-side review before submission. Check that every field that accepts a date uses the MM/DD/YYYY format, all names match exactly across documents, and every yes/no question has been answered — not left blank — even when the answer is no.

After naturalization, update all your records promptly: Social Security Administration, state DMV, employer HR records, financial institutions, and voter registration. If you requested a name change at naturalization, update your name on your Social Security card first (since other agencies use SSA records to verify your name), then apply for a new US passport with your naturalization certificate and updated Social Security card. Completing these updates within 30 days of your ceremony avoids complications with benefits, employment eligibility verification, and international travel.

Keep copies of everything you submit and receive throughout the process in a dedicated naturalization file. This includes your receipt notice, biometrics appointment notice, interview appointment notice, and any written correspondence with USCIS. If you ever need to contact USCIS about your case, having the exact receipt number, filing date, and all correspondence at hand speeds up every interaction significantly.

Most importantly, trust the process once your application is complete and accurate. Processing times feel long — especially when citizenship means the ability to vote, travel on a US passport, and bring family members through different immigration pathways. But USCIS processes roughly 800,000 naturalizations per year, and the overwhelming majority of applicants who are eligible and file correctly become US citizens. Prepare well, file accurately, and the result takes care of itself.