How to become a U.S. citizen: naturalization requirements, Form N-400 and the 2025 civics test

The short answer

Most green card holders can apply for U.S. citizenship after 5 years of permanent residence, or 3 years if married to and living with a U.S. citizen, provided they meet continuous residence, physical presence, good moral character and English and civics requirements. You apply on Form N-400, which costs $710 online or $760 on paper today. If you file on or after October 20, 2025, you take the 2025 civics test: up to 20 questions from a list of 128, with 12 correct answers needed to pass.

U.S. citizenship is the last step of the immigration journey for most green card holders. It brings the right to vote, a U.S. passport, protection from removal, and the ability to sponsor a wider group of relatives. The process, called naturalization, is mostly predictable when you understand the rules and prepare your evidence. This guide walks through eligibility, timing, fees, the interview and the 2025 civics test.

Who can apply for U.S. citizenship

Naturalization is for lawful permanent residents (green card holders). The general requirements come from the Immigration and Nationality Act and are explained in Volume 12 of the USCIS Policy Manual. To apply on the general 5 year basis you must:

• be at least 18 years old when you file;
• have been a lawful permanent resident for at least 5 years;
• have continuous residence in the United States for those 5 years;
• have been physically present in the United States for at least 30 months of those 5 years;
• have lived for at least 3 months in the state or USCIS district where you apply;
• show good moral character for the statutory period;
• show you can read, write and speak basic English;
• show knowledge of U.S. history and government (civics);
• show attachment to the principles of the U.S. Constitution and be willing to take the Oath of Allegiance.

The 3 year rule for spouses of U.S. citizens

If you are married to a U.S. citizen, you may apply after 3 years as a permanent resident if:

• you have been married to and living with the same U.S. citizen spouse for the last 3 years;
• your spouse has been a U.S. citizen for that whole 3 year period;
• you have at least 18 months of physical presence in the 3 years.

Other special routes

Certain groups have different rules, including members and veterans of the U.S. armed forces, some spouses of U.S. citizens employed abroad, and children who may already be citizens through their parents. Children under 18 with a citizen parent often do not need to naturalize at all; they may acquire or derive citizenship automatically and can apply for a certificate of citizenship instead.

Residence and physical presence, explained

These two requirements cause more problems than any other.

Long trips abroad

Continuous residence is judged on the length of your trips outside the United States:

Practical tip: list every trip outside the United States in the statutory period before you apply. Use passport stamps, flight records and the CBP travel history tool. The N-400 asks for all trips of more than 24 hours.

When you can file: the 90 day early filing rule

USCIS accepts the N-400 up to 90 days before you reach the 5 year or 3 year permanent residence mark. You must meet every other requirement on the day you file. USCIS offers an early filing calculator on its website. Filing even a day too early leads to denial and loss of the fee.

How much it costs

The proposed 2026 fee increase

On June 23, 2026, DHS published a proposed rule (Docket USCIS-2026-0265) that would:

• raise the online N-400 fee from $710 to $1,280;
• raise the paper N-400 fee from $760 to $1,330;
• remove the $380 reduced fee;
• end fee waivers for the N-400 and the N-336 appeal form, keeping exemptions for military applicants.

The comment period closed on August 24, 2026. At the time of writing the rule had not been finalized, and the current fees still applied. The fee that counts is the one in force on the day USCIS receives your application, so check the USCIS fee page before you file.

Step by step: the naturalization process

Step 1: Confirm you are eligible

Count your permanent residence time from the "resident since" date on your green card. Add up your days outside the United States. Review any arrests, tax issues, unpaid child support or past immigration problems with a qualified lawyer before filing, because the N-400 asks about all of them.

Step 2: Gather your documents

Most applicants need:

• a copy of both sides of the green card;
• evidence of marital status and, on the 3 year route, proof of your spouse's citizenship and your shared life;
• records of trips abroad;
• court records for any arrest or citation, even if dismissed;
• tax transcripts if relevant to your case;
• the fee payment.

Step 3: File Form N-400

You can file online through a USCIS account or on paper. Online filing costs less, lets you upload evidence and gives you case updates. Answer every question truthfully. Inconsistencies between your N-400 and earlier immigration filings are a common reason for extra scrutiny.

Step 4: Attend biometrics

USCIS schedules an appointment at an Application Support Center to take fingerprints, a photograph and a signature for background checks. In some cases USCIS reuses earlier biometrics.

Step 5: Attend the interview and tests

A USCIS officer reviews your application under oath and gives the English and civics tests. Bring your green card, passport, state ID and the originals of documents you submitted, plus anything the interview notice asks for.

Step 6: Receive the decision

The officer may approve the case, continue it (often to request more evidence or retest you), or deny it. Approved applicants receive a notice for the oath ceremony.

Step 7: Take the Oath of Allegiance

You become a citizen only when you take the oath at a ceremony. You return your green card and receive your Certificate of Naturalization. Then you can apply for a U.S. passport and register to vote.

The English test

The English test has three parts:

• Speaking: assessed by the officer during the interview.
• Reading: read one of up to three sentences correctly.
• Writing: write one of up to three sentences correctly.

English test exemptions

The 2025 civics test

USCIS introduced the 2025 Naturalization Civics Test for applicants who file Form N-400 on or after October 20, 2025. Applicants who filed before that date take the 2008 test.

Applicants who qualify for the 65/20 special consideration are asked 10 questions from a smaller set of 20 and pass with 6 correct.

How to study effectively

• Use the official USCIS question list for the version that applies to you. Studying the wrong list is a common and avoidable mistake.
• Learn answers that apply to you personally, such as your state's senators, your U.S. representative and your state capital, and check they are current close to your interview date.
• Practice out loud, because the test is oral.
• Use the free USCIS study materials and flash cards.

Good moral character

USCIS looks at your conduct during the statutory period (5 or 3 years) and can consider earlier conduct too. Some issues are permanent bars; others are assessed case by case.

If any of these apply to you, speak to a licensed immigration attorney before filing. An N-400 can lead to removal proceedings in serious cases, not just a denial.

Common reasons for delays and denials

1. Filing too early. Count the 90 day window precisely.
2. Too much time abroad. Physical presence and continuous residence are calculated strictly.
3. Undisclosed arrests or citations. Disclose everything, even if a case was dismissed or sealed.
4. Studying the wrong civics test. Check your filing date.
5. Inconsistent marriage evidence on the 3 year route. You must show you lived together for the full period.
6. Missing tax filings. Bring IRS transcripts and payment plans if relevant.

How long naturalization takes

Processing times vary widely by USCIS field office. Check the official USCIS processing times tool for the office handling your case. Once approved, some offices hold same day oath ceremonies; others schedule them weeks later.

What to bring to your interview

Your interview notice lists the documents USCIS wants to see. Most applicants should bring the following, with originals and copies:

Arrive early, bring an organized folder and answer questions directly. If you do not understand a question, ask the officer to repeat it.

After the oath: what to do next

Becoming a citizen changes several records. After your ceremony:

1. Apply for a U.S. passport. Your naturalization certificate is proof of citizenship, but a passport is easier to carry and is needed for international travel.
2. Update your Social Security record so it shows you are a citizen. This avoids problems with work verification and benefits.
3. Register to vote in your state, if you wish. Some ceremonies offer voter registration on site.
4. Keep your certificate safe. Replacing a naturalization certificate is slow and expensive. Do not laminate it or make unauthorized copies for official use.
5. Review family petitions. As a citizen you can now sponsor parents, married children and siblings, and any pending F2A or F2B petitions usually upgrade.

Dual citizenship

U.S. law does not require you to give up your other citizenship when you naturalize, although the oath includes renouncing allegiance to other states. Whether you keep your original nationality depends on the law of that country. Some countries end citizenship automatically when a national naturalizes elsewhere. Check with your country's embassy or consulate before your ceremony if this matters to you.

Naturalization at a glance

Frequently asked questions

When can I file Form N-400?

USCIS accepts applications up to 90 days before you reach the 5 year (or 3 year) permanent residence requirement, provided you meet every other requirement on the day you file.

How much does it cost to apply for U.S. citizenship?

Currently $710 if you file online or $760 on paper, with a reduced fee of $380 for eligible households. DHS proposed in June 2026 to raise the fee to $1,280 online and $1,330 on paper and remove fee waivers; that proposal is not final, so check the USCIS fee page before you file.

What is on the 2025 civics test?

An officer asks up to 20 questions from 128 official questions on American government, history, symbols and holidays. You pass with 12 correct answers, and the officer stops once you reach 12 correct or 9 incorrect.

Can a trip abroad break my continuous residence?

A trip of more than 6 months but less than 1 year creates a presumption that continuous residence was broken, which you can try to rebut with evidence. A trip of 1 year or more breaks continuous residence unless you obtained an approved Form N-470 in advance for certain types of work abroad.

What happens if I fail the English or civics test?

You get a second opportunity to retake the part you failed, usually 60 to 90 days after the first interview. Failing again leads to denial of that application.

Sources

1. USCIS: Form N-400, Application for Naturalization (checked November 6, 2026)
2. USCIS Policy Manual, Volume 12: Citizenship and Naturalization (checked November 6, 2026)
3. USCIS: Naturalization Test and Study Resources (2025 civics test, 128 questions) (checked November 6, 2026)
4. USCIS: Form G-1055, Fee Schedule (checked November 6, 2026)
5. DHS proposed rule: Naturalization Application Fee Adjustments, 91 Fed. Reg. 37,500 (June 23, 2026), Docket USCIS-2026-0265 (checked November 6, 2026)
6. USCIS: Form N-470, Application to Preserve Residence for Naturalization Purposes (checked November 6, 2026)

Cite this page: Jessica Parker and Daniel Brooks, "How to become a U.S. citizen: naturalization requirements, Form N-400 and the 2025 civics test", Immigrantset, last checked November 6, 2026, https://immigrantset.com/guides/us-citizenship-naturalization-n400/