OtterFillHow to fill out Form N-400
Form N-400, “Application for Naturalization”, is the form you file with USCIS to become a U.S. citizen. You fill it in yourself, usually as a lawful permanent resident of at least 5 years, or 3 years if you are married to and living with a U.S. citizen.
Last checked against the official form:
- Form
- N-400
- Edition
- Edition 01/20/25
- Issued by
- U.S. Citizenship and Immigration Services (USCIS)
- Form language
- English
- Who receives it
- USCIS, online through a USCIS account or on paper by mail to the address on the official page; a reduced fee or a fee waiver means filing on paper
- Who fills it in
- You, the applicant, usually 18 or older; you may file up to 90 days before you complete the 5-year or 3-year period
- What happens next
- Biometrics, an interview with the English and civics test, and if USCIS approves, the Oath of Allegiance at a ceremony: only then are you a citizen
- Length
- 14 pages in 16 parts, with 29 pages of instructions. This guide follows the edition dated 01/20/25
- Cost
- Changes over time and is lower online than on paper: check the fee schedule (Form G-1055) linked from the official page
What this form is
Form N-400 is the application to become a naturalized U.S. citizen. USCIS uses it to check that you meet the requirements: in general, time as a lawful permanent resident, continuous residence, physical presence, 3 months in your state or USCIS district, good moral character, English and civics, and willingness to take the Oath of Allegiance. Once you file it properly, its receipt notice extends your green card for 2 years from the card’s expiry date.
The form has 14 pages in 16 parts: Part 1, the basis on which you apply; Parts 2 to 8, information about you, your residence, marriages, children, work and school, and trips abroad; Part 9, 37 numbered questions about your background, military service and the Oath; Part 10, a fee reduction request; Part 11, your signature; Parts 12 and 13, for an interpreter or a preparer; Part 14, extra space. Parts 15 and 16 are signed only at the interview. If you file on paper, send all pages, even blank ones, all from the same edition.
Your choice in Part 1 decides how far back Parts 4, 7 and 8 go: 5 years for the general provision, 3 years if you apply as the spouse of a U.S. citizen or under VAWA, and less for some military and overseas cases. USCIS reads those parts to decide whether you meet the continuous residence and physical presence requirements: for the general provision, at least 30 months (913 days) in the United States during the 5 years; as a spouse, 18 months (548 days) during the 3 years.
Who has to fill it in
You file Form N-400 if, in general, you are 18 or older and one of these applies:
- You have been a lawful permanent resident for at least 5 years (the general provision).
- You have been a lawful permanent resident for at least 3 years and, for those 3 years, married to and living with a spouse who has been a U.S. citizen all that time.
- You became a permanent resident as the spouse or child of a U.S. citizen who abused you, and apply under VAWA after 3 years.
- Your U.S. citizen spouse works abroad for a qualified employer, such as the U.S. Government, for at least 1 year after you file.
- You serve or have served in the U.S. armed forces: at least 1 year of honorable service, or service during a designated period of hostilities, where some requirements do not apply.
Do not use Form N-400 if:
- A parent was a U.S. citizen by birth or naturalized before your 18th birthday: you may already be a citizen; the form points you to Form N-600, Application for Certificate of Citizenship.
- You are more than 90 days away from completing your 5-year or 3-year period: USCIS rejects applications filed too early.
- You need a new green card because yours was lost: the N-400 does not replace it, and USCIS says you generally must still file Form I-90.
- You need to protect your continuous residence during a long job abroad for a qualified employer, such as the U.S. Government: that is a separate form, Form N-470.
Field-by-field instructions
Part 1: Information about your eligibility (select only one box)
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 1Enter Your 9 Digit A-Number: | Your Alien Registration Number, printed on the front or back of your green card. You write it here and at the top of every page. | Write it with 9 digits: if your card shows fewer, add zeros in front, so A12345678 becomes 012345678 after the “A-” printed on the form. If you do not know it, the instructions say to ask the USCIS Contact Center before you file. |
| Part 1, 1.A.General Provision. | You apply after at least 5 years as a lawful permanent resident. | Tick 1.A. Your addresses, jobs and trips in Parts 4, 7 and 8 then cover the last 5 years. |
| Part 1, 1.B.Spouse of U.S. Citizen. | You apply after 3 years as a permanent resident because you are married to a U.S. citizen. | Tick 1.B only if, when you file, you have lived in marital union with your spouse for 3 years and your spouse has been a citizen for those 3 years; you must stay married until the Oath. Send proof of your spouse’s citizenship, your marriage certificate and evidence of life together, such as joint bank statements, a lease or IRS tax transcripts. |
| Part 1, 1.C.VAWA. | You became a permanent resident as the spouse or child of a U.S. citizen who subjected you to battery or extreme cruelty. | Tick 1.C. You apply after 3 years without having to live in marital union, and you do not need to send evidence of your spouse’s citizenship or of the marriage. |
| Part 1, 1.D.Spouse of U.S. Citizen in Qualified Employment Outside the United States. | Your U.S. citizen spouse works outside the United States for a qualified employer, such as the U.S. Government, an American research institution or certain American companies (INA section 319(b)). | Tick 1.D. If you live abroad, choose the USCIS field office for your interview in the list next to it. You must be in the United States for the interview and the Oath, and send proof that the job abroad lasts at least 1 year after you file. |
| Part 1, 1.E.–1.F.Military Service During Period of Hostilities. / At Least One Year of Honorable Military Service at Any Time. | You apply through service in the U.S. armed forces: during a designated period of hostilities (1.E), or at least 1 year of honorable service at any time (1.F). | Tick the one that fits. Current members send Form N-426, Request for Certification of Military or Naval Service; former members send discharge papers such as DD Form 214. Under 1.E you may not need to be a permanent resident; the instructions list the conditions. |
| Part 1, 1.G.Other Reason for Filing Not Listed Above | A basis for naturalization that is not one of the options A to F. | Tick 1.G only if no other box fits, and write your basis on the line beside it. Parts 4, 7 and 8 then cover the last 5 years. |
Part 2: Information about you
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 2, 1.Your Current Legal Name (do not provide a nickname) | Your name as on your birth certificate, unless it changed after birth by marriage, divorce or court order. | Write family name, given name and middle name; no nickname. If your name changed, send the document that changed it, such as a marriage certificate or court order. |
| Part 2, 2.Other Names You Have Used Since Birth | Every other name you have used since birth: maiden name, aliases, nicknames, other spellings, and names used in immigration files or arrests. | Write first, middle and last name for each. The form has room for 2; continue in Part 14. |
| Part 2, 3.Name Change (Optional): Would you like to legally change your name? | An optional request for a court to change your name when you naturalize. | Answer “Yes” and write the new name only if you want a new name at the ceremony. You do not need it if your name already changed by marriage, divorce or court order. It is not available to members of the military or their spouses who naturalize outside the United States. |
| Part 2, 4.USCIS Online Account Number (if any) | The USCIS Online Account Number (OAN), which you have only if you filed a form whose receipt number begins with IOE. | Find it in your online account profile, or at the top of the Account Access Notice if you filed by mail. It is not your A-Number. Leave it as “N/A” if you have none. |
| Part 2, 5.Sex: Male / Female | Male or female. | Choose the sex shown on your birth certificate issued at or closest to the time of birth, or in secondary evidence you gave USCIS. |
| Part 2, 6.Date of Birth (mm/dd/yyyy) | The day you were born. | Write it as mm/dd/yyyy with 8 digits. List any other dates of birth you have ever used in Part 14. USCIS rejects a form without a date of birth. |
| Part 2, 7.If you are a lawful permanent resident, provide the date you became a lawful permanent resident (mm/dd/yyyy). | The day your permanent residence officially began. | Copy the date from your green card as mm/dd/yyyy. USCIS may reject the form if a permanent resident leaves it out. |
| Part 2, 8.–9.Country of Birth / Country of Citizenship or Nationality | The country where you were born, and the country where you are a citizen or national now. | For the country of birth, use its name at the time of your birth. For citizenship, use the country’s current name; if you are a citizen of several, write the one that issued your last passport and list the others in Part 14. If you are stateless, write the country where you were last a citizen. |
| Part 2, 10.Was your mother or father (including adoptive mother or father) a U.S. citizen before your 18th birthday? | Whether your mother or father, including an adoptive parent, was a U.S. citizen before you turned 18. | If “Yes”, you may already be a U.S. citizen: the form says a citizen should not complete Form N-400, and points to Form N-600. |
| Part 2, 11.Do you have a physical or developmental disability or mental impairment that prevents you from demonstrating your knowledge and understanding of the English language or civics requirements for naturalization? | Whether you ask to be excused from the English test, the civics test or both because of a disability or impairment that has lasted or is expected to last 12 months or more. | If “Yes”, send a completed Form N-648 with your application; it does not guarantee the exception. Age exceptions need no form: at 50 with 20 years, or 55 with 15 years as a permanent resident, you skip the English test and may take civics in your language; at 65 with 20 years, you get a simpler civics test. |
| Part 2, 12.a.–12.c.Social Security Update: Do you want the Social Security Administration (SSA) to issue you an original or replacement Social Security card and update your immigration status with the SSA if and when you are naturalized? / Provide your Social Security number (SSN) (if any). / Consent for Disclosure | Whether USCIS should send your information to the Social Security Administration so it issues you a card and records you as a citizen. | To get a card, answer “Yes” to both 12.a and 12.c, the consent. For a replacement card, write your SSN in 12.b. It is optional. |
Part 3: Biographic information
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 3, 1.–2.Ethnicity (Select only one box) / Race (Select all applicable boxes) | Your ethnicity and race, which USCIS uses for background checks. | Tick one box for ethnicity (Hispanic or Latino, or not) and every box that applies for race. |
| Part 3, 3.–4.Height (Feet, Inches) / Weight (Pounds) | Your height and weight in U.S. units. | Height in feet and inches: 5 feet 9 inches is “5” and “09”. Weight in pounds; write “000” if you do not know it. Do not use centimeters or kilograms. |
| Part 3, 5.–6.Eye color (Select only one box) / Hair color (Select only one box) | The color of your eyes and of your hair. | Tick the one box that fits best for each; “Bald (No hair)” and “Unknown/Other” are options. |
Part 4: Information about your residence
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 4, 1.Physical Addresses: Physical Address (Street Number and Name) / City or Town / State / Province / ZIP Code / Postal Code / Country / Dates of Residence From (mm/dd/yyyy) To (mm/dd/yyyy) | Every place you have lived during the period that applies to you, starting with where you live now. | Cover 5 years for 1.A, 1.F and 1.G, 3 years for 1.B and 1.C, and only your current address for 1.D and 1.E, with no gaps; continue in Part 14. If you are homeless, write “homeless” with the city, state and ZIP code. In a shelter or safe house, the city and state are enough. |
| Part 4, 2.–3.Is your current physical address also your current mailing address? / Current Mailing Address (Safe Mailing Address, if applicable) | Where USCIS sends your notices, if it is not your current physical address. | Answer Item 2; if “No”, write the mailing address in Item 3. If you do not feel safe giving it, use a safe address: a P.O. box, a friend, your attorney or an organization helping you. USCIS may reject the form without a valid mailing address. |
Part 5: Information about your marital history
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 5, 1.–2.What is your current marital status? / If you are currently married, is your spouse a current member of the U.S. armed forces? | Your marital status today, and whether your spouse is a current member of the U.S. armed forces. | Tick one: single, never married; married; divorced; widowed; separated; or marriage annulled. If you have never married, go to Part 6. |
| Part 5, 3.How many times have you been married? | How many times you have been married, including now. | Count every marriage: in the United States or abroad, annulled, civil, customary or religious, registered or not. Two marriages to the same person count as 2. |
| Part 5, 4.a.–4.d.Current Spouse's Legal Name / Current Spouse's Date of Birth / Date You Entered into Marriage with Current Spouse / Is your current spouse's present physical address the same as your physical address? | Your current spouse’s name and date of birth, your date of marriage, and whether you live at the same address. | The form asks for Items 4.a to 8 only if you ticked 1.B or 1.D in Part 1; otherwise skip to Part 6. If your spouse lives elsewhere, give the address in Part 14. |
| Part 5, 5.a.–8.When did your current spouse become a U.S. citizen? / Current Spouse's Alien Registration Number (A-Number) (if any) / How many times has your current spouse been married? / Current Spouse's Current Employer or Company | When your spouse became a U.S. citizen, their A-Number, how many times they have been married, and, for 1.D only, their employer. | Tick “By Birth in the United States” or write the date of naturalization. Count your spouse’s marriages the same way as yours, and send proof that their earlier marriages ended. |
Part 6: Information about your children
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 6, 1.Indicate your total number of children under 18 years of age. | How many sons and daughters under 18 you have. | Count all of them: born in the United States or abroad, living with you or not, stepchildren, adopted, missing, and children born outside marriage. Write “None” if you have none. |
| Part 6, 2.Son or Daughter's Name / Residence / Date of Birth / Relationship / Are you providing support for your son or daughter? | Name, date of birth, where each child lives, your relationship and whether you support them. | Use the valid options printed in the columns, such as “resides with me” or “stepchild”. Give the addresses of children who do not live with you, and any child after the third, in Part 14. If a child lives apart, send proof that you support them. |
Parts 7 and 8: Employment, schools and time outside the United States
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 7, 1.Information About Your Employment and Schools You Attended: Employer or School Name / City/Town / State/Province / ZIP Code/Postal Code / Country / Employment/School Dates / Occupation or Field of Study | Where you worked or studied, full time or part time, during the period that applies to you. | Cover 5 years for 1.A, 1.F and 1.G, 3 years for 1.B, 1.C and 1.D, and 1 year for 1.E, starting with your current job or school. Leave no gaps: write “self-employed”, “unemployed” or “retired” where it applies. Include foreign government work such as military, police or intelligence services. |
| Part 8, 1.Time Outside the United States: Date You Left the United States / Date You Returned to the United States / Countries to Which You Traveled | Every trip outside the United States during the period that applies to you. | Start with the latest trip; leave out trips completed within 24 hours. Applicants under 1.D and 1.E list none. For a trip over 6 months, send evidence that you kept your U.S. residence, such as tax transcripts, pay or rent records. |
Part 9: Additional information about you (Items 1 to 22)
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 9, 1.–2.Have you EVER claimed to be a U.S. citizen (in writing or any other way)? / Have you EVER registered to vote or voted in any Federal, state, or local election in the United States? | Whether you have ever claimed to be a U.S. citizen, or registered to vote or voted in a U.S. election. | Answer for your whole life. If you lawfully voted only in a local election where noncitizens may vote, you may answer “No”. Explain any “Yes” in Part 14. |
| Part 9, 3.–4.Do you currently owe any overdue Federal, state, or local taxes in the United States? / Since you became a lawful permanent resident, have you called yourself a “nonresident alien” on a Federal, state, or local tax return or decided not to file a tax return because you considered yourself to be a nonresident? | Whether you owe overdue U.S. taxes, and whether you have treated yourself as a nonresident for tax purposes since becoming a permanent resident. | If you owe overdue taxes, send IRS tax transcripts for 5 years (3 for the spouse basis), your agreement with the tax office and the status of your payments. |
| Part 9, 5.a.–14.Have you EVER: Been a member of, involved in, or in any way associated with any Communist or totalitarian party anywhere in the world? / … Torture? Genocide? … / Have you EVER served in, been a member of, assisted (helped), or participated in any military or police unit? / … any armed group … / … weapons … / … any person under 15 years of age … | Questions on Communist or totalitarian parties, violence, torture or genocide, military, police or armed groups, places of detention, weapons and using children under 15. | Read each item: “EVER” means anywhere in the world, at any time. If you answer “Yes” to 8.a or 8.b, give the country, unit, your rank and dates in Part 14. Explain every “Yes” there. |
| Part 9, 15.a.–16.Have you EVER committed, agreed to commit, asked someone else to commit, helped commit, or tried to commit a crime or offense for which you were NOT arrested? / Have you EVER been arrested, cited, detained or confined by any law enforcement officer, military official (in the U.S. or elsewhere), or immigration official for any reason, or been charged with a crime or offense? | Every crime or offense anywhere in the world: those you committed without arrest, and every arrest, citation, detention or charge. | List each one in the table, even if it was sealed or expunged, happened before you were 18, or someone told you it no longer counts, and send court records (for traffic incidents, only if alcohol or drugs, an arrest or a serious injury were involved). If you were on probation, parole or a suspended sentence, Item 16 asks whether you completed it. |
| Part 9, 17.a.–19.Have you EVER: Engaged in prostitution … / … controlled substances … / Been married to more than one person at the same time? / Married someone in order to obtain an immigration benefit? / Helped anyone to enter, or try to enter, the United States illegally? / Gambled illegally … / Failed to support your dependents … / Made any misrepresentation to obtain any public benefit … / given … false, fraudulent, or misleading … / lied to any U.S. Government officials … | Questions on prostitution, drugs, bigamy, marriage for immigration, smuggling people, illegal gambling, unpaid child support or alimony, and false information to U.S. officials. | Answer each truthfully, explain every “Yes” in Part 14 and send evidence that supports your answers. |
| Part 9, 20.–21.Have you EVER been removed or deported from the United States? / Have you EVER been placed in removal, rescission, or deportation proceedings? | Whether you have ever been removed or deported, or placed in removal, rescission or deportation proceedings. | If “Yes”, explain in Part 14, including the reason. |
| Part 9, 22.a.–22.c.Are you a male who lived in the United States at any time between your 18th and 26th birthdays? / did you register for the Selective Service? / Date Registered / Selective Service Number | Whether you are a man who lived in the United States between your 18th and 26th birthdays, and if so, whether you registered with Selective Service. | Answer “No” to 22.a if you were a lawful nonimmigrant for that whole time. If you registered, write the date and number. If you did not: under 26, register before you apply; from 26 to 31 (to 29 on the spouse basis), explain in Part 14 and send a status information letter. |
Part 9: Military service, titles and the Oath (Items 23 to 37)
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 9, 23.–29.Have you EVER left the United States to avoid being drafted in the U.S. armed forces? / … exemption from military service … / Have you EVER served in the U.S. armed forces? / Are you currently a member of the U.S. armed forces? / … court-martialed … / Have you EVER deserted from the U.S. armed forces? | Questions on avoiding the draft, exemptions, service in the U.S. armed forces, deployment, discharge, court-martial and desertion. | If you never served, answer 25 “No” and go to 30.a. Explain any “Yes” to 23, 24 and 27 to 29 in Part 14. If you move to a new duty station after filing, call the Military Help Line at 877-247-4645. |
| Part 9, 30.a.–30.b.Do you now have, or did you EVER have, a hereditary title or an order of nobility in any foreign country? | Whether you have or had a hereditary title or order of nobility in another country. | Most people answer “No”. If “Yes”, you must be willing to give it up at your ceremony, and list it in 30.b. |
| Part 9, 31.–37.Do you support the Constitution and form of Government of the United States? / Do you understand the full Oath of Allegiance to the United States? / Are you unable to take the Oath of Allegiance because of a physical or developmental disability or mental impairment? / Are you willing to take the full Oath of Allegiance to the United States? / … bear arms … / … noncombatant services … / … work of national importance under civilian direction … | Whether you support the Constitution and are willing to take the Oath of Allegiance, including its parts on bearing arms, noncombatant service and civilian work. | If you answer “No” to any item other than 33, read the Oath section of the instructions: you may ask to change the arms and noncombatant parts for a religious or conscientious objection, and anyone may affirm instead of swearing. |
Part 10: Request for a fee reduction
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 10, 1.–5.b.Request for a Fee Reduction: My household income is less than or equal to 400% of the Federal Poverty Guidelines / Total household income / My household size is / Total number of household members earning income including yourself / I am the head of household | A request to pay a reduced fee because your household income is at or below 400% of the Federal Poverty Guidelines. | If you do not qualify, tick “No” in Item 1 and go to Part 11. Otherwise give total household income, household size, earning members and the head of household, and send tax returns or pay records for each member. A reduced fee means filing on paper. |
Parts 11 to 14: Contact, signature, interpreter, preparer and extra space
| On the form | What it means | How to fill it in |
|---|---|---|
| Part 11, 1.–3.Applicant's Daytime Telephone Number / Applicant's Mobile Telephone Number (if any) / Applicant's Email Address (if any) | How USCIS can reach you. | Give a daytime phone number; a mobile number and email address are optional. |
| Part 11, 4.Applicant's Signature (or signature of a legal guardian, surrogate, or designated representative, if applicable) / Date of Signature (mm/dd/yyyy) | Your signature, certifying under penalty of perjury that your answers are complete, true and correct. | Sign by hand: a typed or stamped name is not accepted, and USCIS rejects an unsigned form. A guardian, surrogate or designated representative may sign for someone who cannot because of a disability. |
| Part 12Interpreter's Contact Information, Certification, and Signature | The details of anyone who read the form and instructions to you in a language you speak fluently. | The interpreter fills in Part 12, names the language and signs. If nobody interpreted, leave it blank but send the page. |
| Part 13Contact Information, Certification, and Signature of the Person Preparing this Application, if Other Than the Applicant | The details of anyone other than you who filled in the form, paid or not. | The preparer completes and signs Part 13. If the same person interpreted and prepared, they complete both Parts 12 and 13. |
| Part 14Additional Information | Extra space for answers that do not fit, and for every “Yes” in Part 9 that needs an explanation. | Write your name and A-Number at the top, the page, part and item number of each answer, and sign and date each sheet. Copy the page if you need more. |
Parts 15 and 16: Completed at the interview
| On the form | What it means | How to fill it in |
|---|---|---|
| Parts 15–16Signature at Interview / Oath of Allegiance | Your signature in front of the officer confirming your answers, and your agreement to take the Oath of Allegiance. | Leave both parts blank: the officer asks you to sign them at the interview. Signing Part 16 does not make you a citizen; that happens at the Oath ceremony. |
Key terms
| Term on the form | What it means |
|---|---|
| Naturalization | How a person who was not born a U.S. citizen becomes one, after applying with Form N-400 and taking the Oath. |
| Lawful Permanent Resident (LPR) / Permanent Resident Card (Green Card) | A person with permanent residence in the United States; the green card is the proof, and its date starts your 5-year or 3-year period. |
| Alien Registration Number (A-Number) | The number DHS gives you, printed on your green card; written on the N-400 with 9 digits. |
| USCIS Online Account Number | A number you have only if you filed a form whose receipt number begins with IOE. It is not the A-Number. |
| Early Filing | Filing up to 90 days before you complete the 5-year or 3-year period. USCIS’s Early Filing Calculator gives the first day. |
| Continuous Residence | Keeping your home in the United States during the 5 or 3 years. An absence of more than 6 months may break it; one of 1 year or more generally does. |
| Physical Presence | The days you are actually in the United States: at least half of the period, such as 913 days in 5 years. Departure and return days count as days in the country. |
| Good Moral Character (GMC) | Behaving to the standard of average citizens of your community during the period before you file and until the Oath. Part 9 asks about it. |
| EVER | Printed in capitals in Part 9: the question covers anything you did anywhere in the world at any time. |
| Naturalization Testing and Exceptions | The English test (speaking, reading and writing) and the civics test on U.S. history and government, and when you may skip or simplify them. |
| Form N-648, Medical Certification for Disability Exceptions | A medical certification you send with the N-400 to ask that you be excused from the English or civics test because of a disability. |
| Form N-470, Application to Preserve Residence for Naturalization Purposes | A form some people working abroad for qualified employers file so that their time abroad does not break their continuous residence. |
| Selective Service | The U.S. registration system for the military draft; nearly all men who are U.S. citizens or immigrants must register from 18 through 25 years of age. |
| Safe Mailing Address | An address where you can safely get mail, for example if you live in a shelter, instead of your home address. |
| Biometric Services Appointment | An appointment where USCIS takes your fingerprints, photograph and signature for background checks. If you do not attend, USCIS may deny the application. |
| Oath of Allegiance | The promise you make at a naturalization ceremony; you become a U.S. citizen only once you take it. |
Common mistakes
- 1
Filing too early
You may file up to 90 days before you complete the period, not earlier, and every other requirement must already be met on the day you file. USCIS rejects early applications; use its Early Filing Calculator.
- 2
Writing the A-Number without 9 digits
If your green card shows 7 or 8 digits, add zeros in front: A1234567 becomes 001234567. Write it at the top of every page.
- 3
Leaving answers blank
Write “N/A” when a question does not apply and “None” when the answer to a number question is zero. Blanks slow the case down.
- 4
Leaving out trips or gaps
List every trip that lasted longer than 24 hours, including short ones to nearby countries, and cover every month of the period in Parts 4 and 7, with “unemployed” where you had no job.
- 5
Not reporting an old or sealed arrest
Part 9 asks about arrests, citations and charges anywhere and at any age, even if expunged or sealed. Not reporting one can lead to denial even when the offense itself would not have.
- 6
Counting marriages or children wrong
Count annulled, religious and customary marriages, and the same person twice if you married twice. List all children under 18, including stepchildren and those living elsewhere.
- 7
Paying the wrong fee
USCIS rejects a form with the wrong fee, the wrong payment method, or more than the fee. Check the fee schedule on the day you file.
- 8
Signing with a typed name, or not at all
Sign Part 11 by hand. USCIS rejects an unsigned form; a photocopy or scan of a hand-signed form is accepted.
- 9
Using correction fluid or old pages
Scanners can read through correction tape. Start a new form instead, and send all 14 pages of the same edition.
- 10
Not answering Selective Service correctly
Men who lived in the United States between 18 and 26 answer 22.a “Yes” unless they were lawful nonimmigrants the whole time. Under 26, register before you apply.
Questions and answers
When can I apply for U.S. citizenship?
Generally after 5 years as a permanent resident, or 3 years if you are married to and living with a U.S. citizen. You may file up to 90 days before that date; USCIS’s Early Filing Calculator shows the first day.
How much does Form N-400 cost?
Fees change: check Form G-1055, the fee schedule, linked from the N-400 page on the day you file. Filing online costs less than on paper. If your household income is at or below 400% of the Federal Poverty Guidelines you may ask for a reduced fee in Part 10, or for a fee waiver with Form I-912; both mean filing on paper.
Can I file Form N-400 online?
Yes, through a USCIS online account, unless you ask for a reduced fee or a fee waiver: then you must file the paper form.
What documents do I send with Form N-400?
A copy of both sides of your green card, plus what applies to you: marriage and citizenship evidence for the spouse basis, Form N-648 for a disability exception, Form N-426 for current military members, court records for any arrest, and evidence for trips over 6 months. Documents in another language need a full certified English translation.
Do I list short trips to Canada or Mexico?
Yes, every trip outside the United States in the period, unless you left and came back within 24 hours. Start with the most recent.
What is on the citizenship test?
If you filed on or after October 20, 2025, the officer asks up to 20 of 128 civics questions and you pass with 12 correct. For English you read 1 of 3 sentences, write 1 of 3, and the officer judges your speaking at the interview. If you fail a part, you are retested on it within 60 to 90 days.
Can I travel abroad after filing?
The instructions say an absence of 1 year or more after you file also breaks continuous residence. Make sure you can receive your biometrics and interview notices, and tell USCIS within 10 days if you move.
My green card is expiring. Can I still apply?
Yes. The N-400 receipt notice extends your green card for 2 years from its expiry date. If the card is lost, you generally still need Form I-90.
I am a conditional resident. Can I apply?
In most cases USCIS can approve your N-400 only after your Form I-751 or I-829 to remove conditions is approved.
When do I become a citizen?
Only when you take the Oath of Allegiance at a naturalization ceremony after approval. You then receive your Certificate of Naturalization and hand in your green card.
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