Path to U.S. citizenship: when and how to apply

Step 1 — Find your path to citizenship

USCIS’s first step is to check whether you are already a citizen (USCIS — 10 Steps): if a parent was a U.S. citizen before you turned 18, you may already have a claim, filed on Form N-600 (USCIS — G-1151).

The main paths (USCIS — Citizenship and Naturalization):

• 5 years as a permanent resident — the most common path (USCIS — LPR of 5 years);
• 3 years as a permanent resident, married to a U.S. citizen — “living in marital union” with your spouse during those 3 years and while USCIS decides your case (USCIS — Married to a U.S. citizen);
• military service, with its own rules (USCIS — Citizenship and Naturalization).

USCIS’s online Eligibility Tool “does not determine if you are actually eligible”; USCIS decides after you apply (USCIS — Eligibility Tool).

Step 2 — Learn the main requirements

On the 5-year path, USCIS requires (USCIS — LPR of 5 years):

• Age: at least 18 when you file Form N-400.
• Continuous residence: at least 5 years as a permanent resident, immediately before you file. It must also continue until you become a citizen (USCIS Policy Manual).
• Physical presence: at least 30 months in the U.S. out of those 5 years — 913 days, in the N-400 instructions (USCIS — N-400 Instructions). USCIS counts the days you leave and return as days in the U.S.; you prove the time with documents, not just your green card (USCIS Policy Manual).
• Where you live: at least 3 months in the state or USCIS district that covers your home before you file (USCIS Policy Manual). Students who depend financially on their parents may apply where they study or where their family lives (USCIS — LPR of 5 years).
• Good moral character for 5 years before you file (USCIS — LPR of 5 years) and until the Oath of Allegiance (USCIS Policy Manual).
• English and civics: basic reading, writing and speaking, plus knowledge of U.S. history and government (USCIS — LPR of 5 years).
• Attachment to the Constitution, and taking the Oath of Allegiance (USCIS — LPR of 5 years), in which you sincerely renounce all foreign allegiance (USCIS Policy Manual).

On the marriage path: 3 years of continuous residence, 18 months of physical presence and 3 years of good moral character (USCIS — Married to a U.S. citizen). The N-400 checklist asks for proof that your spouse has been a U.S. citizen for those 3 years (USCIS — N-400).

Exceptions. Under the “50/20” and “55/15” exceptions (age and years as a permanent resident), you skip the English test but still take the civics test, which you may take in your own language with an interpreter you bring. People with certain disabilities can request an exception with Form N-648 (USCIS — Exceptions).

Trips abroad. You won’t meet the continuous residence requirement if you left the U.S. without USCIS’s approval for 1 year or more during the required period, or after filing. After an absence of more than 6 months but less than 1 year, you must show you didn’t break your residence (USCIS — N-400 Instructions). See traveling abroad as a green card holder.

Men: the N-400 asks about Selective Service (USCIS — N-400 Instructions); see Selective Service for immigrant men.

Step 3 — Know the 2025–2026 changes

• Good moral character. A USCIS memorandum of August 15, 2025 says this review “involves more than a cursory mechanical review focused on the absence of wrongdoing” (USCIS — PM-602-0188). Officers weigh positive factors, such as community involvement, family caregiving, education, stable lawful employment and “compliance with tax obligations.” They also look more closely at conduct, even acts that are “technically lawful,” like “reckless or habitual traffic infractions” (USCIS — PM-602-0188).
• Neighborhood investigations. A policy alert of August 25, 2026 “reintroduces personal investigations, also known as neighborhood investigations” (USCIS — PA-2026-10). Unless USCIS waives it, investigators may interview people near your home and work about your conduct, reputation and community ties (USCIS Policy Manual). Reference letters are optional, preferably from U.S. citizens who know you, such as neighbors or co-workers; USCIS doesn’t consider letters from relatives. It says at least two letters sent with your N-400 can help it decide whether to waive the investigation (USCIS Policy Manual).
• New civics test. If you file on or after October 20, 2025, you take the 2025 civics test (USCIS — Interview and Test). See preparing for the citizenship test.

These policies can change; re-check the USCIS pages before you file.

Step 4 — Pick your date: the 90-day window

USCIS says you may file Form N-400 “90 calendar days before you complete your continuous residence requirement,” on the 5-year path or the 3-year marriage path (USCIS — N-400). The N-400 instructions add two cautions (USCIS — N-400 Instructions):

• you must still meet every other requirement on the day you file (for example, 3 years of marriage, or the age and years for an English test exception);
• “We will reject your application if you submit it too early.”

The instructions also point to an Early Filing Calculator (USCIS — N-400 Instructions), but that link now leads to a page in USCIS’s archive, labeled out of date (USCIS — Early Filing Calculator, archived). The Policy Manual explains how USCIS counts the 90 days (USCIS Policy Manual).

Step 5 — Prepare and file Form N-400

• Online or on paper. Online filing uses a free USCIS online account (USCIS — N-400; USCIS — 10 Steps).
• Fee help. To request a reduced fee or a fee waiver, you must file on paper (USCIS — N-400). Read who qualifies on the official pages (USCIS — Reduced fee; USCIS — I-912).
• Documents. The N-400 checklist depends on your situation (marriage records, court records, proof of residence after long trips). If you owe taxes, it asks for a signed agreement with the tax office showing you filed and arranged to pay. Foreign-language documents need a certified translation (USCIS — N-400).
• Sign it. “We will reject any unsigned form” (USCIS — N-400).
• Tell the whole truth. Knowingly hiding or falsifying a material fact leads to denial and possible criminal prosecution (USCIS — N-400 Instructions).

USCIS then sends a receipt notice (USCIS — 10 Steps); keep a copy of your application (USCIS — G-1151).

Step 6 — Go to your biometrics appointment

If USCIS needs your biometrics (fingerprints, photograph and/or signature), it mails you an appointment notice. There you sign an oath that your application is true; if you miss the appointment, USCIS may deny your application (USCIS — N-400 Instructions). This photo may appear on your Certificate of Naturalization, so USCIS recommends dressing for it (USCIS — N-400).

Step 7 — The interview, the test and the decision

The officer places you under oath and asks about your application and your eligibility (USCIS Policy Manual). Unless you qualify for an exception, you also take the English test (speaking, reading and writing) and the civics test. You get two attempts; a failed part is retested 60 to 90 days later (USCIS — Interview and Test).

Bring your appointment notice (USCIS — 10 Steps); your green card, a state ID and all your passports, valid and expired (USCIS — G-1151); and IRS tax transcripts, especially after a trip abroad of more than 6 months (USCIS — N-400 Instructions).

The decision: granted, continued (for example, more documents needed, or a failed first test) or denied (USCIS — 10 Steps). After a denial, Form N-336 lets you request a hearing (USCIS — N-336).

Step 8 — Take the Oath of Allegiance

You may take the oath the same day as your interview; otherwise USCIS mails a notice, Form N-445, with the date and place (USCIS — Ceremonies). At the ceremony (USCIS — Ceremonies):

• an officer reviews your N-445 questionnaire, so complete it beforehand;
• you return your green card;
• “You are not a U.S. citizen until you take the Oath of Allegiance”;
• you check your Certificate of Naturalization and report errors before leaving.

If you can’t attend, return the N-445 to your local office with a letter asking for a new date; missing the ceremony more than once may lead to denial (USCIS — Ceremonies).

Step 9 — First steps as a citizen

Only citizens can vote in federal elections, serve on a federal jury and run for federal office; citizens travel with a U.S. passport and generally get priority when petitioning for family; some government jobs require citizenship (USCIS — Should I Consider Citizenship?). Until your oath, see voting and other civic rules for noncitizens.

After the ceremony (USCIS — Ceremonies):

• Passport: an application comes in your welcome packet; allow time before any trip.
• Voting: you get a voter registration application after the oath.
• Social Security: update your record, generally at least 10 days after the ceremony.