Citizenship through a U.S. citizen parent

For the modern rule, citizenship arises by operation of law when all statutory conditions are satisfied. Form N-600 normally documents that citizenship; it does not create it.

• At least one parent is a U.S. citizen by birth or naturalization.
• The child is under 18 when the statutory conditions are satisfied.
• The child is residing in the United States in the legal and physical custody of the citizen parent pursuant to a lawful admission for permanent residence.

Congress also created special INA 320(c) rules for certain children residing abroad with U.S. citizen armed-forces members or U.S. government employees. Those cases should not be forced into the ordinary “residing in the United States” rule.

INA 322 is different: it is an application-based path for a qualifying child who regularly resides outside the United States. Form N-600K is the operative application.

• The child regularly resides outside the United States and is under 18.
• A qualifying U.S. citizen parent (or, in specified circumstances, a U.S. citizen grandparent) meets the physical-presence requirement.
• The child is in the legal and physical custody required by the statute and USCIS instructions.
• The child generally must be temporarily present in the United States pursuant to a lawful admission for the interview and oath, subject to special rules for children residing abroad with qualifying U.S. armed-forces members.