How to become a US citizen: Requirements, procedures, and processing times

More than 800,000 people become U.S. citizens each year, according to data from U.S. Citizenship and Immigration Services. Most follow a common path: obtaining a green card (permanent residency) first, then applying for U.S. citizenship.

In Vietnam, searches for "how to become a U.S. citizen," "U.S. citizenship requirements," "U.S. naturalization process," or "how long does it take to get U.S. citizenship" have steadily increased each year. This indicates a growing demand for long-term residency and a stable future for oneself and family.

This article will help you:

• Understand how to become a U.S. citizen through common categories

• Accurately grasp the latest U.S. citizenship requirements

• Know the practical path: from green card to citizenship

• Avoid mistakes that lead to prolonged processing or rejection

Whether you have a green card, are married to a U.S. citizen, have U.S. citizen parents, or serve in the U.S. military, each path has its own requirements and strategies. Understanding them correctly from the beginning will save you years of waiting and unnecessary costs.

If your goal is a sustainable future in the U.S., start by understanding the process of becoming a U.S. citizen in a practical and directed manner.

Part 1: U.S. Naturalization Procedures through Permanent Residency

Step 1: How to Get a U.S. Green Card

Family-sponsored Green Card

This is the most common path for Vietnamese people looking into how to immigrate to the U.S. long-term.

• If the sponsor is a U.S. citizen, they can sponsor:

  • Spouse

  • Unmarried children under 21

  • Parents

  • Siblings

  • Married children or unmarried children over 21

• If the sponsor is a permanent resident (green card holder):

  • Only spouse and unmarried children can be sponsored

Practical notes:

• Spouse, parent, and unmarried child under 21 categories for U.S. citizens usually process faster.

• Sibling or married adult child categories have multi-year visa wait times.

• Applications require proof of a genuine and legal relationship; avoid document errors that can prolong processing time.

Employment-based Green Card

If you plan to develop your career in the U.S., this is a sustainable path towards U.S. citizenship.

• Have a full-time job offer from a U.S. company.

• The company sponsors your green card application.

• Some individuals with extraordinary abilities (in science, arts, business, sports, etc.) can self-petition without a company sponsor.

Practical experience:

• Employment-based applications require clear proof of qualifications, degrees, and experience.

• The process often includes obtaining labor certification before filing the green card application.

• This is a suitable option for young professionals with high expertise or long-term investors.

Refugee or Asylum-based Green Card

Individuals recognized as refugees or who have been granted asylum in the U.S. can apply for a green card after:

• 1 year of legal residency in the U.S. under this category.

• Meeting character and legal status requirements.

Important note:

• The application needs clear evidence to support the asylum claim.

• After obtaining a green card, you will then start counting the waiting period to be eligible to apply for U.S. citizenship.

Understanding how to obtain a U.S. green card correctly from the start will help you determine the appropriate path before considering the next step of how to become a U.S. citizen. A green card is not just a right to long-term residency but also a crucial legal foundation for building a stable life and preparing for future naturalization applications.

Step 2: Residency Requirements for U.S. Naturalization

Lawful Admission and Valid Green Card

• You must be granted Lawful Permanent Resident status.

• No fraud in the visa or green card application process.

• No serious violations that could affect legal status.

Practical experience: If there were interruptions in green card status or previous immigration issues, it's advisable to carefully review your records before applying for U.S. citizenship.

Continuous Residency for at Least 5 Years

• You must have lived continuously in the U.S. for at least 5 years before the application date.

• Example: if you plan to apply in January 2026, you must have been a permanent resident since January 2021.

• Cannot leave the U.S. for too long, interrupting continuous residency.

Practical notes:

• If you leave the U.S. for more than 6 months, the continuous residency may be re-evaluated.

• If you leave the U.S. for more than 1 year, you will almost certainly have to restart the residency period (except in special cases).

This is what many people search for when asking: how long after getting a green card can I apply for U.S. citizenship.

Actual Physical Presence in the U.S. for at Least 30 Months

• Within those 5 years, you must have been physically present in the U.S. for at least 30 months (approximately 913 days).

• This is a “physical presence” requirement – different from continuous residency.

Many people misunderstand that just having 5 years is enough. In reality, if you frequently travel abroad for extended periods, you might not meet the physical presence requirement even if you've had a green card for 5 years.

Residency for at Least 3 Months in the Filing State

• Before applying for U.S. naturalization, you must have lived for at least 3 months in the state or district under the jurisdiction of the USCIS office where you are filing.

• If you've recently moved states, you should wait 3 months before applying.

This is especially important for those who frequently change residences due to work.

Step 3: Personal Requirements for U.S. Naturalization

18 Years Old or Older

• You must be at least 18 years old at the time of filing for naturalization.

• If under 18, U.S. citizenship depends on your parents' status under separate provisions.

This is a basic but mandatory requirement for all U.S. citizenship applications.

Basic English Language Ability

• Must be able to read, write, and speak basic English.

• Required to take the naturalization exam, which includes:

  • An English language test

  • A civics test

What you need to know:

• The English test is not overly complex; it primarily assesses basic conversational ability.

• Some elderly individuals and long-term residents may be exempt from or have reduced English requirements as per regulations.

Demonstrate Good Moral Character

You must be deemed a person of “good moral character,” meaning:

• No serious criminal record

• No tax fraud or prolonged tax debt

• No immigration law violations

• Fulfill all financial and legal obligations

Practical experience:

• USCIS typically reviews your conduct over the past 5 years (or 3 years if applying based on marriage).

• Minor infractions may not significantly affect your application, but fraud or serious criminal convictions can lead to rejection.

You not only need to meet the residency duration but also demonstrate your readiness to become a responsible citizen. Properly preparing for personal requirements from the start will help the review process go smoothly and increase your chances of approval.

Step 4: Filing the U.S. Naturalization Application (Form N-400)

Download and Complete Form N-400

• Download Form N-400 – Application for Naturalization from the official USCIS website.

• You can fill it out directly on a computer or print it and write in black ink.

• Read the instructions carefully before filling it out to avoid errors in personal information, residency history, or travel history.

Practical experience:

• Information must be absolutely consistent with your green card, passport, and tax records.

• Many applications are delayed due to underreporting time spent outside the U.S. or incorrect residency addresses.

Prepare Supporting Documents

When applying for U.S. citizenship, you will need to attach:

• Copy of both sides of your Green Card (Permanent Resident Card)

• Required photos (if filing a paper application)

• Relevant documents if there are changes in name, marital status, or criminal record (if any)

Important notes:

• Do not send originals unless requested.

• Missing documents can cause the application to be returned at the initial stage.

Pay naturalization fees

• Application fee: $640

• Biometrics fee (fingerprinting): $85

• Total: $725 (based on fees applied in recent years; should recheck at the time of application submission)

Payment method:

• Check or money order

• Payable to “U.S. Department of Homeland Security”

• Do not abbreviate the agency name

Incorrect payee name is a common error that causes applications to be returned.

Determine where to file the application

• You can file online or mail paper applications to the correct processing center based on your state of residence.

• Check the exact address based on where you live.

• You can call the USCIS hotline to confirm if you are unsure of the filing location.

Submitting Form N-400 officially marks the beginning of your process to become a U.S. citizen. Thorough preparation from the start will help reduce the risk of your application being returned and shorten the waiting time for an interview.

Step 5: Attend biometrics appointment for US naturalization

Receive appointment letter from USCIS

• USCIS will send an appointment letter stating:

  • Appointment date

  • Appointment time

  • Biometrics location

• You must attend at the designated time.

• If you cannot attend, you must follow the instructions in the letter to reschedule.

Practical notes:

• Failure to attend on schedule may delay or close your application.

• You should bring your appointment letter and green card to the center.

Fingerprinting, photo, and signature capture

At the appointment, you will:

• Have your fingerprints taken

• Have your photo taken

• Provide an electronic signature

The process is quick, usually taking about 15-30 minutes if it's not too crowded.

The purpose of this step is to verify your identity and ensure the accuracy of your application.

FBI background check

• Your fingerprints will be sent to the FBI for a background check.

• USCIS will assess whether you meet the "good moral character" standard.

• If you have a criminal record or legal issues, further explanation may be required for your application.

This is a crucial step before you are invited for a U.S. naturalization interview.

Prepare for English and civics tests

After completing biometrics, you should start focusing on studying:

• English test (reading, writing, basic conversation)

• U.S. civics test

USCIS often provides official study materials. It's recommended to use the updated question sets to avoid studying incorrect content.

Step 6: Prepare for the interview and naturalization test

Attend the interview with a USCIS officer

During the U.S. naturalization interview, you will:

• Reconfirm the information provided in Form N-400

• Answer questions about:

  • Residence history

  • Employment

  • Time spent outside the U.S.

  • Tax and legal obligations

• Sign to reconfirm information if there are any corrections

Practical experience:

• Questions often closely follow the information you provided.

• If there are changes in address, employment, or marital status, they must be updated truthfully.

• Answer clearly, concisely, and to the point.

English test during the interview

The English test consists of 3 basic skills:

• Read an English sentence

• Write an English sentence

• Answer simple conversational questions

Note:

• Academic English is not required.

• Content often revolves around personal information or basic daily life questions.

• Some older individuals or long-term residents may be exempt or allowed to take the test in their native language, according to regulations.

If you're wondering how difficult the U.S. naturalization test is, the practical answer is: it's not difficult if you study the right content.

Civics Test

• The officer will ask a maximum of 10 questions from the official 100 questions.

• You need to answer at least 6 questions correctly to pass.

Content revolves around:

• U.S. History

• Constitution

• Government Structure

• Rights and Responsibilities of Citizens

Effective preparation methods:

• Study the updated question set from USCIS.

• Take online practice tests multiple times to get familiar with the questions.

• Practice answering concisely and clearly.

Attend preparation classes if needed

If you feel unsure, you can:

• Attend English and civics test preparation classes in your local community.

• Find free or low-cost support organizations for permanent residents.

• Practice online with sample tests.

The interview is the most important milestone. Serious preparation will not only help you pass the test but also demonstrate your readiness to become a responsible and knowledgeable U.S. citizen.

Step 7: Attend the U.S. naturalization interview

Receive interview appointment letter from USCIS

• The letter will state:

  • Interview date

  • Specific time

  • Location of the USCIS office

• You must attend as scheduled.

• If you cannot attend, you must follow the instructions in the letter to reschedule.

Practical notes:

• Failure to attend on schedule may result in your application being denied or having to reapply from scratch.

• You should arrive 15-30 minutes early for security procedures.

Take the English and civics tests during the interview

During the interview, you will:

• Answer questions to verify the information in Form N-400

• Take the English test (reading, writing, basic conversation)

• Take the U.S. civics test

If you demonstrate clear English proficiency during the conversation, the officer may be flexible with the test portion. However, you should still prepare thoroughly to avoid any risks.

Many people ask: do I have to retake the U.S. naturalization interview, can I retake the U.S. naturalization test if I fail. In reality, if you do not pass, you are usually allowed to retake the failed portion at a subsequent appointment.

Prepare all necessary documents before the interview date

Before the interview, USCIS will send a list of required documents (often called a checklist accompanying the notice).

Typically includes:

• Original Green Card

• Current and old passports (if any)

• Marriage or divorce certificates (if applicable)

• Name change documents (if any)

• Proof of tax payments for recent years (if requested)

Practical experience:

Bring both copies and originals for verification.

• Organize documents clearly to avoid confusion when asked.

The interview is the final evaluation step before approval. Thorough preparation of documents and practicing answers will help you enter the interview room feeling proactive and confident.

Step 8: Oath of Allegiance and U.S. Naturalization

Receive notice to attend the oath ceremony (Form 455)

• USCIS will send an invitation letter with Form 455.

• The letter will state:

  • Date of ceremony

  • Start time

  • Ceremony location

Before attending, you must:

• Answer the questions on the back of Form 455 (regarding legal status, departure, new violations, etc.).

• Confirm that there have been no significant changes since the interview.

Practical notes:

• If there are changes such as arrest, legal violations, or extended absences from the U.S. after the interview, you must truthfully declare them.

• Concealing information may lead to delays or cancellation of naturalization.

Take the Oath of Allegiance

At the ceremony, you will:

• Return your green card

• Swear allegiance to the United States

• Pledge to uphold the U.S. Constitution and laws

After this point, you officially become a U.S. citizen – no longer a permanent resident.

This is a significant milestone because:

• You have the right to apply for a U.S. passport

• You have the right to vote

• You have full rights and responsibilities as a citizen

Receive the Certificate of Naturalization

At the end of the ceremony, you will be given your Certificate of Naturalization.

What to do immediately afterward:

• Carefully check your full name, date of birth, and personal information on the certificate.

• If you find any errors, immediately report them to the responsible officer at the ceremony.

• Safeguard the certificate carefully as it is an important legal document.

The naturalization ceremony is not just an administrative procedure but a milestone marking a change in legal status. Completing this step officially concludes your journey to U.S. citizenship and opens a new chapter with full rights as a U.S. citizen.

Part 2: How to obtain U.S. citizenship through marriage to a citizen

Step 1: Get a U.S. green card through marriage

File a marriage petition (Form I-130)

• The U.S. citizen spouse must file Form I-130 (Petition for Alien Relative) with USCIS.

• The application must include:

  • Legal marriage certificate

  • Proof of bona fide marriage (joint photos, joint accounts, lease agreements, joint tax returns, etc.)

Important note:

• USCIS will thoroughly verify the authenticity of the marriage.

• If the marriage is suspected of being fraudulent, the application may be denied and have long-term consequences for immigration status.

If currently in the U.S. legally: File for Adjustment of Status (Form I-485)

If you:

• Entered the U.S. legally (tourist visa, student visa, work visa, etc.)

• Are currently in the U.S.

You can:

• File Form I-485 (Application to Register Permanent Residence or Adjust Status)

• Often filed concurrently with Form I-130 to shorten processing time

Advantages of adjusting status in the U.S.:

• No need to leave the U.S. to wait for a visa

• Can apply for a work permit while waiting for adjudication

Practical experience:

• Absolutely do not overstay your visa before filing (except in certain exceptions).

• The application must truthfully declare your entry process.

If currently outside the U.S.: Interview at the Consulate

If you are living outside the United States:

• You must wait for the I-130 petition to be approved.

• Then apply for an immigrant visa.

• Attend an interview at the nearest U.S. Embassy or Consulate.

Upon visa approval and entry into the U.S.:

• You will receive your green card after completing entry procedures.

• In some cases, you may need to file Form I-485 to complete the process.

Note:

• Prepare the petitioner's financial documents thoroughly (Affidavit of Support).

• Interviews often focus on the authenticity of the relationship.

After obtaining a marriage-based green card, you can apply for U.S. citizenship after 3 years (instead of 5 years) if you are still living together and maintaining your marriage to a U.S. citizen.

Step 2: Marriage Interview for Green Card

Purpose of the interview

The immigration officer will:

• Verify the authenticity of the relationship

• Check for consistency in the couple's answers

• Cross-reference information with the submitted application

If there are suspicions, the couple may be interviewed separately to compare answers.

Common questions

Questions can be very mundane, for example:

• Where and when did you two meet?

• How many people attended your wedding?

• Who usually cooks? Who pays the bills?

• What did you two do for your last birthday?

• What are your daily routines as a couple?

The purpose is not to make things difficult, but to check for naturalness and consistency.

Note: Some questions may be private. You should answer briefly and to the point, without speculating or adding extra details.

Practical preparation before the interview

• Review all the information declared in Forms I-130 and I-485.

• Agree on key timelines: when you met, wedding date, previous shared addresses.

• Prepare additional joint evidence:

  • Family photos

  • Joint lease or home ownership documents

  • Joint bank accounts

  • Joint bills, insurance, tax returns

Practical experience:

• Answer naturally, as if telling your own true story.

• If you don't remember a small detail exactly, you can say "I don't recall" instead of guessing.

• Calmness and consistency are more important than overly long answers.

Mistakes to avoid

• Memorizing answers rigidly like a script.

• Giving conflicting answers between the two of you.

• Stating information that differs from the application.

Marriage-based naturalization can shorten the citizenship process to 3 years, but the green card interview is the most crucial "gate." Thorough, honest, and clear preparation will help you pass smoothly and get closer to your goal of U.S. citizenship.

Step 3: 3-Year Residency Requirement for Naturalization

Hold a green card for 3 years before filing

• You must have been a permanent resident (green card holder) for at least 3 consecutive years before the date of filing Form N-400.

• The timeframe is calculated from the date on the green card, not the marriage date.

Practical notes:

• You can file up to 90 days early before the 3-year mark (if other conditions are met).

• Filing too early before the time requirement is met will result in rejection.

Continuous residency and sufficient physical presence

During those 3 years, you must:

• Maintain continuous residence in the U.S.

• Be physically present in the U.S. for at least 18 months

Important note:

• Leaving the U.S. for more than 6 months may interrupt continuous residency.

• Leaving the U.S. for more than 1 year usually requires restarting the residency period (except in special cases).

Many applications are delayed due to inaccurate calculation of entry and exit dates.

Maintain marriage to a U.S. citizen for the entire 3 years

• You must have been living in a bona fide marriage with your U.S. citizen spouse for the entire 3 years before filing the application.

• Your spouse must have been a U.S. citizen for that entire period (not just recently naturalized).

If divorced before filing:

• You will have to wait the full 5 years under the regular permanent resident category.

This is the core condition that shortens the naturalization period for marriage-based U.S. citizenship.

Reside in the filing state for at least 3 months

• Before applying for U.S. citizenship, you must have lived for at least 3 months in the state or USCIS district where you file your application.

• If you have recently moved, you should wait 3 full months before applying.

In reality, the marriage-based category shortens the waiting time from 5 years to 3 years, but it comes with stricter conditions regarding the continuity of marriage and residency. Calculating the correct time to file your application will help you take advantage of this category and move faster on your journey to US citizenship.

Step 4: Individual Requirements for Marriage-Based Naturalization

18 years of age or older

• You must be at least 18 years old at the time of filing Form N-400.

• This condition applies to all naturalization categories.

This is a basic but mandatory requirement for all US citizenship applications.

Ability to use basic English

You must be able to:

• Read simple English sentences

• Write basic English sentences

• Communicate during the interview

The English test takes place during the naturalization interview.

Practical notes:

• High proficiency is not required.

• Some older or long-term residents may be exempt or have reduced requirements as per regulations.

Demonstrate good moral character

You need to prove that you are a person of “good moral character,” meaning:

• No serious criminal record

• No tax fraud

• No prolonged tax debt

• No evasion of child support obligations

• No immigration law violations

USCIS typically reviews conduct for the most recent 3 years (because you are naturalizing through marriage), but some serious past offenses can still have an impact.

Practical experience:

• If you have had legal issues, you should consult an attorney before filing your application.

• Honesty is always better than concealing information.

Must have entered the U.S. legally

• You must have lawfully entered the United States.

• You cannot be in the U.S. illegally and then apply for citizenship simply by marrying a U.S. citizen.

• The process of adjusting status must follow proper immigration procedures.

This is a common misconception among those looking for how to obtain US citizenship through marriage. Marriage does not automatically legalize your immigration status if you have previously committed serious immigration violations.

Step 5: Filing the Naturalization Application for Marriage-Based Cases

Complete Form N-400 (Application for Naturalization)

• Download Form N-400 from the official USCIS website.

• Read the instructions carefully before filling out the form.

• Fill in all information completely and truthfully:

  • Residency history

  • Dates of entry and exit

  • Marital status

  • Employment history

  • Tax obligations

Important notes:

• Information must match previous I-130, I-485, and green card records.

• Inaccurate or incomplete reporting of time spent outside the U.S. is a common error that leads to requests for additional evidence.

Prepare supporting documents

Before filing, carefully check the list of required supporting documents. These typically include:

• Copy of both sides of green card

• Marriage certificate

• Proof of spouse's U.S. citizenship (U.S. passport or naturalization certificate)

• Relevant documents if name has changed

• Legal documents if there have been criminal issues

Practical experience:

• Do not send original documents unless requested.

• Organize your application clearly to avoid requests for additional evidence.

Pay naturalization fees

Based on the fees applied in recent years:

• Application fee: $640

• Biometrics fee: $85

• Total: $725

Pay by:

• Money order or check

• Payee: “U.S. Department of Homeland Security”

• Do not abbreviate the agency's name

Incorrectly writing the payee's name is a common technical error that causes applications to be returned.

Determine the correct filing address

• The filing address depends on the state where you reside.

• You can check online or call the USCIS hotline to confirm.

• Filing at the wrong address will delay the processing time.

Filing Form N-400 is the official milestone that transitions you from the "eligible" stage to the "awaiting review" stage. Thorough preparation and correct filing from the outset will help shorten the processing time and increase the likelihood of approval on the first attempt.

Step 6: Fingerprinting for US Citizenship

Receive appointment letter from USCIS

• USCIS will send a notice specifying:

  • Appointment date

  • Appointment time

  • Location of the Application Support Center (ASC)

• You must attend at the designated time.

If you cannot attend:

• Follow the instructions in the letter to reschedule.

• Do not miss an appointment without notice, as this may lead to your application being suspended.

How the fingerprinting process works

At the appointment, you will:

• Have your fingerprints taken digitally

• Have your photo taken

• Provide an electronic signature

The process usually takes only about 15–30 minutes if it's not busy.

Bring:

• Original appointment letter

• Green card

• Photo identification (if requested)

Purpose of fingerprinting

• USCIS sends your fingerprints to the FBI for a background check.

• They will verify whether you meet the "good moral character" standard.

If you have a criminal record or legal issues:

• USCIS may request additional explanatory documents.

• Some serious cases may affect the outcome of your US citizenship application.

The fingerprinting step is not complex but very important. Successfully completing this stage will help your application move smoothly to the interview and citizenship test.

Step 7: US Citizenship Interview

Purpose of the interview

During the interview, the immigration officer will:

• Review all information in Form N-400

• Confirm that there have been no significant changes since the application was filed

• Assess the truthfulness and legality of the application

They may ask about:

• Residency history

• Dates of entry and exit

• Employment

• Marital status

• Tax obligations

If there are any changes (moving, changing jobs, divorce, etc.), you must declare them truthfully.

Prepare all necessary documents according to the checklist

Before the interview, USCIS will send a list of documents to bring. These typically include:

• Original green card

• Current and old passports

• Marriage or divorce certificates (if applicable)

• Proof of recent tax filings

• Relevant documents if there have been legal issues

Practical experience:

• Organize documents clearly by category.

• Bring copies for verification.

• Arrive at least 15–30 minutes early for security procedures.

Things to keep in mind when answering

• Answer concisely and to the point.

• Do not guess if you don't remember accurately; you can say "I don't recall."

• Do not provide information different from what was declared in the application.

The interview is the final verification step before approval and invitation to take the oath. Thorough preparation, honesty, and calmness will help you successfully navigate this stage and move closer to your goal of becoming a U.S. citizen.

Step 8: U.S. Citizenship Test: Civics and English

English Test for U.S. Citizenship

The English test consists of 3 parts:

• Read an English sentence

• Write an English sentence

• Answer basic conversational questions with the USCIS officer

Required level:

• Only basic level, no complex academic knowledge required

• Content usually revolves around personal information or simple daily life questions

Practical notes:

• If you communicate well throughout the interview, the test might be more relaxed.

• Some elderly individuals or long-term residents may be exempt or have reduced requirements according to regulations.

U.S. Civics Test

• The officer will ask a maximum of 10 questions from the official 100-question pool.

• You need to answer at least 6 questions correctly to pass.

Question topics typically relate to:

• U.S. History

• Constitution

• Government structure

• Citizen rights and responsibilities

Effective study methods:

• Study the official question set published by USCIS.

• Practice answering concisely and clearly.

• Take practice tests multiple times to get familiar with the questioning style.

Attend preparation classes if needed

If you are not confident, you can:

• Find local naturalization preparation classes by searching by zip code.

• Attend free support classes from community organizations.

• Practice online with sample tests.

Practical experience from many U.S. citizenship applications: Those who pass on the first try are usually people who study the official question set correctly and practice answering instinctively. There's no need to study extensively; just focus on the content required by USCIS.

Step 9: Attend the U.S. Naturalization Oath Ceremony

Receive Oath Ceremony Notice (Form 455)

• USCIS will send an invitation letter with Form 455.

• The letter will specify:

  • Date of ceremony

  • Start time

  • Location of the ceremony

Before attending, you must:

• Answer the questions on the back of Form 455 (related to changes in legal status after the interview).

• Confirm no new violations or significant changes.

Practical notes:

• If there are changes such as arrests, legal violations, or changes in marital status, you must declare them truthfully.

• Concealing information can affect the citizenship decision.

Take the Oath of Allegiance

At the ceremony, you will:

• Return your green card

• Pledge allegiance to the United States

• Commit to upholding the U.S. Constitution and laws

After this point, you officially transition from a permanent resident to a U.S. citizen.

Receive Certificate of Naturalization

At the end of the ceremony, you will be given your Certificate of Naturalization.

Immediate actions required:

• Carefully check your full name, date of birth, and personal information on the certificate.

• Report any errors immediately for timely correction.

• Keep it safe as it is an important legal document for:

  • Applying for a U.S. passport

  • Sponsoring relatives

  • Exercising citizen rights

The oath ceremony is not just an administrative procedure but the final legal milestone. Completing this step officially makes you a U.S. citizen with full rights and responsibilities as stipulated by law.

Part 3: U.S. Citizenship Eligibility through Parents

Condition 1: U.S. Citizenship through Parents

Born when both parents are U.S. citizens

You automatically acquire U.S. citizenship through your parents if:

• Both parents were U.S. citizens at the time of your birth.

• They were legally married to each other.

• At least one of them had resided in the U.S. or its territories before you were born.

In this case:

• You do not need to apply for U.S. citizenship through naturalization.

• You can apply for a U.S. passport or a certificate of citizenship to prove your citizenship.

What does "resided in the U.S." mean?

At least one of the two parents must have:

• Actually resided in the U.S. or its territories before the child's birth.

• The specific period of residence may depend on the individual case and the law applicable at the time of birth.

This is an important factor. If parents are U.S. citizens but have never resided in the U.S. before the child's birth, the transmission of citizenship may not be automatic.

What to do to confirm citizenship

Even with automatic citizenship, you should:

• File a Consular Report of Birth Abroad (CRBA) if born outside the U.S.

• Or apply for a U.S. passport to confirm citizen status.

Citizenship by bloodline is an "automatic" path and does not require going through the naturalization process. However, proving and registering correctly from the outset will help avoid legal complications later on.

Condition 2: U.S. Citizenship when one parent is a citizen

Conditions regarding parents' marital status

• Parents must be legally married at the time the child is born.

• One of them must be a U.S. citizen when the child is born.

If parents are not married, the regulations will be different and each case needs to be considered separately.

Residency requirements for the U.S. citizen parent

The U.S. citizen father or mother must have:

• Actually resided in the U.S. or its territories for at least 5 years before the child's birth.

• Of which, there must be at least 2 years of residency after turning 14 years old.

This condition ensures a genuine connection to the United States before transmitting citizenship to the child.

Practical notes:

• Residency time does not need to be continuous.

• Multiple periods can be accumulated.

• Proof of residence is required (academic records, tax returns, employment, residency, etc.).

Birth date requirement

• The child must have been born on or after November 14, 1986 for this provision to apply.

• If born before this date, different laws apply and must be reviewed according to older regulations.

This is an important detail but often overlooked when researching how to obtain U.S. citizenship through parents.

What to do to confirm citizenship

Even with automatic citizenship, you should:

• File a Consular Report of Birth Abroad (CRBA) if born outside the U.S.

• Or apply for a U.S. passport to confirm citizen status.

Citizenship by bloodline is the most direct legal path, but it requires accurate proof of the parent's residency time. Preparing sufficient evidence from the beginning will help the citizenship confirmation process proceed smoothly and avoid disputes later on.

Condition 3: U.S. Citizenship when parents are not married

If the mother is a U.S. citizen

The child will automatically acquire U.S. citizenship at birth if:

• The mother is a U.S. citizen at the time of birth.

• The mother had actually been present in the U.S. or its territories for at least 1 continuous year before the child's birth.

Important points:

• The father is not required to be a U.S. citizen.

• Parents are not required to be married.

In practice, this case is usually simpler as it only requires proving the mother's nationality and period of residency.

If the father is a U.S. citizen

If the father is a U.S. citizen and the mother is not, the conditions are stricter. The following must be met:

• The father was a U.S. citizen at the time the child was born.

• Clear and convincing evidence that the father is the biological father (DNA test or legal documents).

• The father must sign a written agreement to financially support the child until they turn 18.

• The father must meet the residency requirements in the U.S. according to the law applicable at the time of birth.

Practical notes:

• The father's residency requirement is often similar to the 5-year rule (including 2 years after age 14) if current law applies.

• Missing a financial support agreement or lack of biological proof are common reasons for delayed applications.

What to do to confirm citizenship

Even if you automatically qualify, you should:

• File a Consular Report of Birth Abroad (CRBA) if born outside the U.S.

• Or apply for a U.S. passport to confirm citizenship.

The unmarried parent category does not require an exam or oath, but it does demand clear legal proof. Preparing all evidence from the beginning will help the citizenship confirmation process proceed smoothly and avoid future risks.

Condition 4: Automatic U.S. citizenship after birth

Applicable Conditions (born after 02/27/2001)

A child will automatically acquire U.S. citizenship if they meet all of the following conditions:

• At least one parent is a U.S. citizen.

• The child is under 18 years old when the conditions are met.

• The child is residing in the United States legally (e.g., with a green card).

• The U.S. citizen parent has legal and physical custody of the child.

When all these factors are met, the child does not need to pass a citizenship test or take an oath.

Residency and Custody Requirements

The two often misunderstood factors are:

• The child must be physically living in the U.S., not just on paper.

• The U.S. citizen parent must have legal custody and provide direct care (physical custody).

If parents are divorced, documentation proving legal custody is required.

Cases for children born before February 27, 2001

If the child was born before this date:

• Different laws will apply.

• Residency period and parental citizenship status requirements may be stricter.

• It is necessary to review the legal regulations in effect at that time.

In practice, many families confuse automatic U.S. citizenship with naturalization through Form N-400. For children who qualify under the 2001 law, citizenship can be recognized automatically without a test or oath.

Condition 5: U.S. Citizenship for Adopted Children

Adopted before age 16 and living in the U.S. for 2 years

A child can automatically acquire U.S. citizenship if:

• Legally adopted by U.S. citizen parents before turning 16 years old.

• The adoptive parents have legal and physical custody.

• The child and adoptive parents have resided together in the U.S. for at least 2 years.

• The child is legally residing in the United States (e.g., has a green card).

Key points:

• There must be a legal adoption order in accordance with the law.

• The 2-year period does not necessarily have to be continuous but must meet the requirements.

Entry under IR-3 or IH-3 classification

If the child:

• Was adopted abroad and the adoption was finalized.

• Enters the U.S. with an IR-3 (orphan) or IH-3 (Convention adoptee) visa.

• The adoption was finalized before the child turned 18 years old.

In this case, the child typically automatically acquires U.S. citizenship upon entry if all legal conditions are met.

This category usually applies when the adoptive parents are U.S. citizens and the adoption was finalized abroad.

Entry under IR-4 or IH-4 classification

If the child:

• Enters the U.S. with an IR-4 or IH-4 visa to finalize the adoption procedures in the U.S.

• The adoption is finalized before the child turns 18 years old.

After the adoption is legally finalized in the U.S. and the child meets the residency requirements, the child can be recognized as a citizen.

Practical notes:

• IR-4 and IH-4 visas typically require completing adoption procedures in a U.S. court.

• Only after legal finalization will the child be eligible for automatic citizenship.

The adoption category is a separate mechanism for minors. Adoptive parents should complete citizenship confirmation procedures (apply for a U.S. passport or certificate of citizenship) to ensure the child's long-term legal rights.

Part 4: Naturalization through Military Service

Step 1: Good Moral Character Requirements for Naturalization

No serious legal violations

USCIS will consider:

• Criminal records

• Immigration fraud

• Perjury in applications

• Serious offenses (especially serious felonies)

Typically:

• USCIS assesses conduct within 3 years (marriage-based) or 5 years (standard permanent residency) before filing.

• However, serious past violations can still have long-term effects.

Fulfill all legal obligations

You must demonstrate that you are law-abiding, including:

• Filing and paying taxes in full

• No long-term tax debt or a clear plan to repay debt

• Fulfilling child support obligations (if any)

• Complying with Selective Service registration requirements if applicable

Failure to pay taxes or evasion of financial obligations are common reasons for U.S. citizenship applications to be delayed.

Honesty in all applications

• Do not conceal information

• Do not misrepresent criminal history, marital status, or entry/exit records

• Do not use false documents

USCIS has the right to cross-reference information with numerous federal databases. Concealment can be more serious than the initial violation.

If you have a criminal record or legal issues

• Do not speculate about your chances of approval or denial.

• Consult an immigration lawyer before submitting Form N-400.

• Some offenses can lead to denial or even deportation proceedings.

The good moral character factor is not just a legal requirement but also an overall assessment of civic responsibility. Preparing transparent applications, fulfilling obligations, and proactively addressing legal issues before applying will significantly increase your chances of approval.

Step 2: English Language and Civics Knowledge Requirements

Demonstrate English proficiency

You need to show that you can:

• Read a simple English sentence

• Write a basic English sentence

• Communicate directly with the interviewing officer

The English test takes place during the naturalization interview.

Practical tips:

• No high academic proficiency is required.

• Content usually revolves around personal information and everyday questions.

• If you communicate well throughout the interview, the test will be smoother.

U.S. Civics Test

In addition to English, you must demonstrate knowledge of:

• U.S. government structure

• The Constitution

• U.S. history

• Rights and responsibilities of citizens

Test format:

• The officer will ask up to 10 questions from the official list of 100 questions.

• You need to answer at least 6 questions correctly to pass.

Practical tips:

• Studying the official question set is sufficient.

• Concise, to-the-point answers are more likely to pass than long-winded ones.

Prepare before the test

To increase your chances of passing on the first attempt:

• Download the official civics test questions from the USCIS website.

• Take practice tests multiple times to familiarize yourself with the question format.

• Practice answering reflexively instead of rote memorization.

The English and civics tests are not designed to trick you, but to ensure you have a basic understanding of the country you are about to become a citizen of. Preparing with the right materials and practicing regularly will help you pass smoothly.

Step 3: U.S. Naturalization for Peacetime Service

Honorable service for at least 1 year

• You must serve in the U.S. military for at least 1 year.

• The period of service must be considered honorable service.

This means:

• No serious disciplinary violations.

• No dishonorable discharge.

Possess a valid green card

• You must be a lawful permanent resident (possess a U.S. green card).

• Military service does not automatically replace the requirement for lawful residency.

In reality, many people mistakenly believe that simply enlisting is enough. However, legal immigration status remains a mandatory requirement.

File the application at the right time

You must file your application:

• While still in active duty, or

• Within 6 months of discharge.

If you exceed this deadline, you may have to apply under regular provisions and will no longer receive the priority given to military personnel.

Advantages of military naturalization

Compared to the regular process:

• May be exempt from certain residency time requirements.

• Applications are often processed faster.

However, you must still:

• Meet good moral character standards.

• Pass the English and civics tests (unless eligible for exemption).

Peacetime military service is a special path for those who contribute to the United States. Preparing your application on time and ensuring valid legal status will help you maximize the benefits of this category.

Step 4: U.S. Naturalization for Wartime Service

Service during designated periods of conflict

• A period of “hostilities” declared by the U.S. President.

• The U.S. has been considered to be in this phase since 2002 and it will last until an official declaration of its end.

If you serve during this period and your service is deemed honorable service, you may be eligible to apply for U.S. citizenship under priority provisions.

Can apply immediately

Unlike peacetime service:

• No requirement to serve for a full year.

• Can apply for U.S. citizenship almost immediately while in active duty.

In many cases, residency requirements are also waived or significantly relaxed.

Must still meet basic requirements

Despite priority, you still need to:

• Serve honorably.

• Meet good moral character standards.

• Complete background checks.

Some English and civics knowledge requirements still apply, unless eligible for exemption under specific regulations.

Advantages of wartime naturalization

• Processing time is usually faster.

• May be exempt from some long-term residency requirements.

• Provides an opportunity to become a U.S. citizen much earlier than through the regular process.

Wartime service is a special mechanism to recognize the contributions of military personnel to the United States. However, preparing the application correctly and ensuring clear legal status remains a decisive factor for quick approval.

Step 5: Filing the U.S. Naturalization Application for Military Service

Contact the responsible department at your unit

• Each military unit usually has personnel responsible for assisting with naturalization procedures.

• Typically part of the Personnel Office or the Judge Advocate General (JAG) Office.

The first thing you should do is:

• Contact them directly for guidance.

• Receive the application package and specific instructions for military personnel.

Practical experience:

• Working through your unit helps ensure the application is accurate and processed faster.

• Avoid filing on your own without confirmation from your commanding officer.

Complete Form N-400 and Form N-426

You will need to prepare:

• Form N-400 – Application for Naturalization.

• Form N-426 – Request for Certification of Military or Naval Service.

Form N-426 must be certified by your military unit before being submitted to USCIS. This document proves your eligibility under military provisions.

Important note:

• If Form N-426 is missing, the application may be returned.

• Carefully review all information before submitting.

Waiver of filing fees

A major advantage for military applicants:

• Exemption from the N-400 filing fee.

• No biometrics fee, unlike regular applicants.

This significantly reduces costs compared to other U.S. citizenship application types.

USCIS support for military personnel

USCIS has a dedicated team to support:

• Active duty military personnel.

• Military families.

You can:

• Call the dedicated military support line during business hours.

• Or send an email to the specialized department for answers.

Close coordination with your unit and correct completion of forms are the most crucial factors. Thanks to priority mechanisms and fee waivers, this is one of the fastest and most convenient ways to become a U.S. citizen if you are serving honorably in the military.

Step 6: Oath of Allegiance to Finalize U.S. Citizenship

Commitment to the U.S. Constitution

When taking the oath, you will:

• Pledge allegiance to the United States.

• Respect and defend the Constitution.

• Renounce allegiance to other countries (as per the oath content).

• Be ready to perform civic duties as required by law.

This is a mandatory requirement for all U.S. citizenship applications.

Time of oath administration

• Usually takes place at a naturalization ceremony after the application is approved.

• For military personnel, it may be held at their unit or a special location as arranged by USCIS.

After completing the oath:

• You officially become a U.S. citizen.

• You will receive a Certificate of Naturalization.

Legal significance of the oath

Before taking the oath, you are still a permanent resident.
After taking the oath, you have all the rights and responsibilities of a citizen, including:

• The right to apply for a U.S. passport.

• The right to vote.

• The right to sponsor relatives as a citizen.

The oath is the final legal milestone confirming your commitment to the U.S. legal system and Constitution. Completing this step means you officially transition to U.S. citizenship.

Can you apply for U.S. citizenship with a criminal record?

Not all criminal records lead to immediate denial

USCIS will consider:

• The type of offense (minor or serious).

• When the offense occurred (within the last 3 or 5 years).

• Whether you have completed your legal obligations.

Some minor violations may not automatically lead to rejection. However, serious crimes (especially those involving fraud, drugs, or violence) may disqualify you from naturalization.

The risk is not just denial

In some serious cases:

• USCIS may refer the case for deportation consideration.

• Information declared on Form N-400 can lead to a review of your immigration status.

Therefore, filing an application without carefully assessing the risks can lead to more significant consequences than mere denial.

Why consult an immigration lawyer?

If you have a criminal record, you should:

• Bring all court records and related documents for the attorney to review.

• Clearly identify the offense under immigration law (which sometimes differs from state criminal law).

• Assess eligibility before filing Form N-400.

U.S. immigration law has many complex provisions, and some seemingly minor offenses can be classified as a “crime involving moral turpitude” under federal law.

Do not misrepresent or conceal information

• USCIS has access to federal databases and criminal records.

• Concealing a criminal record can be considered immigration fraud, making the situation more serious.

Having a criminal record does not automatically mean rejection, but it is an issue that needs to be professionally evaluated before applying. Proactively consulting with an attorney will help you understand your chances of success and avoid unnecessary legal risks.

References

1. AllLaw. (n.d.). How to get citizenship through military service. Retrieved from http://www.alllaw.com/articles/nolo/us-immigration/how-get-citizenship-through-military-service.html
2. AllLaw. (n.d.). How to get a green card after marriage to a U.S. citizen. Retrieved from http://www.alllaw.com/articles/nolo/us-immigration/how-get-green-card-after-marriage-citizen.html
3. AllLaw. (n.d.). What happens at a green card marriage interview. Retrieved from http://www.alllaw.com/articles/nolo/us-immigration/what-happens-green-card-marriage-interview.html
4. Cury, V. (n.d.). Expert interview. Immigration Attorney.
5. FindLaw. (n.d.). How to become a U.S. citizen by marriage. Retrieved from https://archive.findlaw.com/blog/how-to-become-a-us-citizen-by-marriage/
6. Illinois Legal Aid Online. (n.d.). Good moral character and immigration status. Retrieved from https://www.illinoislegalaid.org/legal-information/good-moral-character-and-immigration-status
7. U.S. Citizenship and Immigration Services (USCIS). (n.d.). Green card. Retrieved from https://www.uscis.gov/green-card
8. U.S. Citizenship and Immigration Services (USCIS). (n.d.). Green card for employment-based immigrants. Retrieved from https://www.uscis.gov/green-card/green-card-eligibility/green-card-for-employment-based-immigrants
9. U.S. Citizenship and Immigration Services (USCIS). (n.d.). Form N-400 instructions. Retrieved from https://www.uscis.gov/sites/default/files/document/forms/n-400instr.pdf
10. U.S. Citizenship and Immigration Services (USCIS). (n.d.). What to expect during the naturalization process. Retrieved from https://my.uscis.gov/citizenship/what_to_expect
11. U.S. Citizenship and Immigration Services (USCIS). (n.d.). Civics practice test (2008 version). Retrieved from https://www.uscis.gov/citizenship/civics-practice-test-2008
12. U.S. Citizenship and Immigration Services (USCIS). (n.d.). I am married to a U.S. citizen. Retrieved from https://www.uscis.gov/citizenship/learn-about-citizenship/citizenship-and-naturalization/i-am-married-to-a-us-citizen
13. U.S. Citizenship and Immigration Services (USCIS). (n.d.). I am the child of a U.S. citizen. Retrieved from https://www.uscis.gov/citizenship/learn-about-citizenship/i-am-the-child-of-a-us-citizen
14. U.S. Citizenship and Immigration Services (USCIS). (n.d.). Naturalization through military service. Retrieved from https://www.uscis.gov/military/naturalization-through-military-service

Translated by: Lesley Collins Tran.