A Mexican national can become a U.S. citizen through naturalization, which requires first holding a green card, meeting federal residency and character rules, passing English and civics tests, and taking the Oath of Allegiance. Most applicants qualify after five years as a lawful permanent resident, or three years if married to and living with a U.S. citizen. The naturalization stage itself typically takes six to ten months from filing to oath, but the years spent obtaining and holding the green card stretch the full timeline much longer.
Step One: Get a Green Card
Citizenship starts with lawful permanent residence. For Mexican nationals, the most common paths are family sponsorship and employment sponsorship. Immediate relatives of U.S. citizens (spouses, unmarried children under 21, and parents) have no annual cap and move fastest. Other family preference categories carry country-specific backlogs that fall hard on Mexico.
The October 2025 Visa Bulletin shows how long those waits run. Unmarried adult children of U.S. citizens (F1) were being processed from priority dates in November 2005. Married adult children (F3) sat at September 2004. Siblings of adult citizens (F4) waited from November 2006. The F2A category for spouses and minor children of green card holders was relatively current at February 2024.1U.S. Department of State. Visa Bulletin for October 2025 Employment-based green cards through the EB-1, EB-2, and EB-3 preference categories are another route, requiring employer sponsorship or demonstrated extraordinary ability.2U.S. Citizenship and Immigration Services. Green Card for Employment-Based Immigrants
Once the green card is in hand, the clock starts on the residency you need before you can file for naturalization.
Who Qualifies for Naturalization
You must be at least 18 when you file.3eCFR. 8 CFR Part 316 – General Requirements for Naturalization Most applicants need five years of continuous residence as a permanent resident. If you are married to a U.S. citizen and have lived together in marital union for three years, the residency requirement drops to three.4eCFR. 8 CFR Part 319 – Spouses of United States Citizens You can file Form N-400 up to 90 calendar days before you complete that continuous residence period, so long as you will meet it by the time of your interview.5U.S. Citizenship and Immigration Services. N-400, Application for Naturalization
Physical Presence and Time Abroad
Under the five-year track, you must have been physically present in the United States for at least 30 months, roughly 913 days. Under the three-year spousal track, the requirement is 18 months.6U.S. Citizenship and Immigration Services. Chapter 4 – Physical Presence
Travel is allowed, but long trips carry consequences. An absence of more than six months but less than a year creates a presumption that you broke your continuous residence, which you can rebut with evidence like a maintained U.S. home, continued employment, or filed tax returns. An absence of one year or more automatically breaks continuous residence, and you would generally need to wait four years and one day after returning before applying.7U.S. Citizenship and Immigration Services. Chapter 3 – Continuous Residence If work requires extended time abroad, filing Form N-470 before you leave can protect your continuous residence clock.
Good Moral Character
USCIS must find that you have good moral character throughout the statutory period and up to your oath. Officers review criminal history, tax compliance, and general conduct. An aggravated felony conviction is a permanent bar. Fraud to obtain immigration benefits, failure to pay court-ordered child support, and drug convictions during the statutory period can also lead to denial.8Office of the Law Revision Counsel. 8 USC 1427 – Requirements of Naturalization
Men who lived in the United States between ages 18 and 26 must have registered with the Selective Service.9U.S. Citizenship and Immigration Services. Form N-400 Application for Naturalization A knowing failure to register can defeat both the character requirement and the officer’s assessment of your willingness to accept civic duties.10Selective Service System. USCIS Policy Manual – Selective Service Registration
Filing Form N-400
Form N-400 asks for detailed personal history across the full statutory period. Every residential address with months and years lived there. Every job, with employer names, addresses, and titles. Every trip outside the United States, with exact departure and return dates. Passport stamps are the most reliable way to reconstruct travel. Any trip over six months will need extra documentation showing you did not abandon residence.
Common supporting documents include a valid Permanent Resident Card, tax returns or IRS transcripts covering the statutory period, and, for spousal filers, a marriage certificate plus proof of the spouse’s citizenship. Any foreign-language document, including a Mexican birth certificate, must come with a certified English translation.
You can file online through a USCIS account or by mail. The filing fee is $710 for online submissions and $760 for paper, with biometric processing included in both.5U.S. Citizenship and Immigration Services. N-400, Application for Naturalization A full fee waiver is available on Form I-912 if household income is at or below 150% of the Federal Poverty Guidelines.11U.S. Citizenship and Immigration Services. Form I-912, Instructions for Request for Fee Waiver A reduced $380 fee applies to household incomes between 150% and 400% of the guidelines.12U.S. Citizenship and Immigration Services. Fact Sheet – Form N-400 Filing Fees Active-duty military members pay no fee.
Biometrics, Interview, and the Tests
After USCIS accepts your application, you receive a biometrics appointment at an Application Support Center for fingerprints, a photo, and a signature. Missing it without rescheduling can lead to denial.
The naturalization interview takes place at a USCIS field office, typically five to eight months after filing. An officer reviews your N-400 responses and evaluates your English through the conversation itself. You must also read aloud one of three English sentences and write one of three sentences the officer dictates.13eCFR. 8 CFR Part 312 – Educational Requirements for Naturalization
The 2025 Civics Test
If you filed your N-400 on or after October 18, 2025, you take the 2025 civics test. It draws from a pool of 128 questions. The officer asks up to 20, and you must answer at least 12 correctly.14U.S. Citizenship and Immigration Services. 128 Civics Questions and Answers (2025 Version) Applicants 65 or older with at least 20 years as permanent residents take a reduced version: 10 questions from a designated subset of 20, with 6 correct answers needed.15Federal Register. Notice of Implementation of 2025 Naturalization Civics Test Applicants who filed before October 18, 2025, take the older 2008 test drawn from 100 questions, with 10 asked and 6 correct answers required.16U.S. Citizenship and Immigration Services. Civics (History and Government) Questions for the Naturalization Test
Waivers and Retesting
The English requirement is waived entirely for applicants over 50 with at least 20 years as permanent residents, or over 55 with at least 15 years. These applicants may take the civics test in their native language. Applicants with a physical or developmental disability or mental impairment can request a waiver of both tests using Form N-648.17Office of the Law Revision Counsel. 8 USC 1423 – Requirements as to Understanding the English Language, History, Principles and Form of Government of the United States
Failing either portion is not final. USCIS schedules a second exam within 60 to 90 days, and you only retake the portion you failed. Failing again, or missing the retake without a reasonable rescheduling request, results in denial.18U.S. Citizenship and Immigration Services. Chapter 4 – Results of the Naturalization Examination
The Oath Ceremony
Once your application is approved, USCIS sends Form N-445, the Notice of Naturalization Oath Ceremony. It includes a short questionnaire asking whether anything has changed since the interview, including arrests, marital status, or trips abroad. Answer honestly. False statements at this stage can unwind the whole case.
At the ceremony, you take the Oath of Allegiance in a public setting. The oath includes a declaration that you renounce allegiance to foreign sovereigns and will support and defend the U.S. Constitution.19eCFR. 8 CFR Part 337 – Oath of Allegiance You surrender your Permanent Resident Card and receive a Certificate of Naturalization (Form N-550), your primary proof of U.S. citizenship and the document you use to apply for a passport.20U.S. Citizenship and Immigration Services. USCIS Redesigns Citizenship and Naturalization Certificates You become a citizen the moment you complete the oath, not when the certificate arrives.
Do You Lose Your Mexican Nationality?
No. Mexico amended Article 37 of its constitution in 1997, and since the amendment took effect on March 20, 1998, no person who is Mexican by birth can be stripped of Mexican nationality, even after voluntarily acquiring citizenship in another country. You keep your Mexican nationality after taking the U.S. Oath of Allegiance, despite the oath’s renunciation language, and you can hold both a U.S. and a Mexican passport.
The rule differs for people who became Mexican through naturalization rather than by birth. Naturalized Mexican citizens can lose their Mexican nationality by voluntarily acquiring another country’s citizenship. For Mexican-born applicants, dual nationality is fully permitted under Mexican law.
After You Are Naturalized
A few updates should happen quickly. Apply online with the Social Security Administration for a replacement card that reflects your updated citizenship status; you will schedule an appointment and bring your Certificate of Naturalization, and the new card typically arrives within 5 to 10 business days.21Social Security Administration. Update Citizenship or Immigration Status Apply for a U.S. passport at a passport acceptance facility using the certificate as proof of citizenship. Register to vote in federal, state, and local elections.
Foreign Account Reporting
This catches many new citizens from Mexico off guard. If you hold bank, investment, or other financial accounts in Mexico with a combined value exceeding $10,000 at any point during the year, you must file a Report of Foreign Bank and Financial Accounts (FBAR) through FinCEN’s electronic filing system by April 15, with an automatic extension to October 15. The obligation applies to all U.S. citizens, and penalties for non-compliance are severe.22Internal Revenue Service. Comparison of Form 8938 and FBAR Requirements
A separate requirement, Form 8938 (Statement of Specified Foreign Financial Assets), applies at higher thresholds. If you are single and your foreign financial assets exceed $50,000 on the last day of the tax year or $75,000 at any point during the year, you must attach Form 8938 to your federal return. For married couples filing jointly, the thresholds are $100,000 and $150,000.22Internal Revenue Service. Comparison of Form 8938 and FBAR Requirements If you still hold accounts in Mexico, plan for these forms during tax season.
If Your Application Is Denied
USCIS denies applications for failure to meet continuous residence or physical presence, lack of good moral character, inability to pass the tests, or pending removal proceedings, among other reasons.18U.S. Citizenship and Immigration Services. Chapter 4 – Results of the Naturalization Examination
If your application is denied after the interview, you can request a hearing by filing Form N-336 within 30 calendar days of receiving the denial, or 33 days if the decision was mailed. The hearing fee is $780 online or $830 by paper, with fee waiver eligibility available.23U.S. Citizenship and Immigration Services. N-336, Request for a Hearing on a Decision in Naturalization Proceedings24U.S. Citizenship and Immigration Services. G-1055 Fee Schedule A different USCIS officer conducts the hearing and reviews the original decision. If that hearing also results in denial, you can seek judicial review in federal district court.