Citizenship for children: automatic citizenship vs. Form N-600

Under INA 320 (the Child Citizenship Act), a child born outside the U.S. becomes a U.S. citizen automatically, with no application, test or oath, when all of these are true at the same time before the child turns 18:

• At least one parent is a U.S. citizen, by birth or through naturalization (adoptive parents included).
• The child is under 18.
• The child is a lawful permanent resident (has a green card).
• The child lives in the U.S. in the legal and physical custody of the U.S. citizen parent.

The conditions can be met in any order, as long as all are met before the 18th birthday. The rule applies to children who met them on or after February 27, 2001.

When you take the oath, each of your children who is under 18, has a green card, and lives with you in your legal and physical custody becomes a citizen at that moment.

If a child gets a green card after your oath, the child becomes a citizen on the day the last condition is met, as long as it is before age 18. A child without a green card, or who was already 18 when the last condition was met, does not become a citizen this way and generally has to naturalize on their own with Form N-400.

Since a 2020 law, children living abroad with a citizen parent who is a U.S. service member or government employee stationed abroad can also qualify, if the other requirements are met.

Automatic citizenship needs no document to exist, but your child will need proof. Two common options:

• A U.S. passport from the Department of State (travel.state.gov). A valid passport is proof of citizenship.
• A Certificate of Citizenship from USCIS, requested with Form N-600.

The N-600 costs $1,385 on paper or $1,335 online as of October 2026. It is free for certain adopted children, and for current or former members of the U.S. armed forces requesting a certificate for themselves (children of service members do not get this exemption). A fee waiver with Form I-912 is possible on paper. A parent or legal guardian files for a child under 18, and USCIS waives the oath for children under 14.

INA 322 is for children who live outside the U.S. and so cannot use automatic citizenship. A citizen parent applies with Form N-600K (same fee as the N-600). In general:

• The child must be under 18 and live abroad in the legal and physical custody of the citizen parent.
• The citizen parent must have been physically present in the U.S. for at least 5 years, including at least 2 years after age 14. If not, a citizen grandparent's physical presence can be used.
• The child must be lawfully admitted and physically present in the U.S., in lawful status, for the approval and the oath. USCIS waives the oath for children under 14.

The process must be finished before the child turns 18, so apply early.

A child born outside the U.S. may already be a citizen at birth if a parent was a U.S. citizen at the time, depending on the parent's time in the U.S. and the law in force on the child's birth date. These children usually document citizenship with a Consular Report of Birth Abroad from a U.S. embassy or consulate, a passport, or a Form N-600.

Rules for children born at different times, adopted children and stepchildren are complex. Check the USCIS Policy Manual, Volume 12, Part H, or talk to an immigration attorney or DOJ-accredited representative. This guide is general information, not legal advice.