A child born abroad to a US citizen parent is often a US citizen from birth, without applying. Under INA §§ 301 and 309, it depends on whether the parents were married, whether one or both were citizens, and whether the citizen parent lived in or was physically present in the United States long enough before the birth. The law in effect on the birth date controls.
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| Governing law | INA §§ 301 and 309, as in effect on the date of birth |
|---|---|
| Key requirement | The citizen parent’s residence or physical presence in the United States before the birth |
| Proof abroad | Consular Report of Birth Abroad, applied for at a US embassy or consulate before age 18 |
| Proof in the US | A US passport, or a Certificate of Citizenship on Form N-600 |
| Child living abroad | Form N-600K under INA § 322, where the child did not acquire citizenship at birth |
| Attorney fee | A flat fee, agreed in writing; government fees paid separately |
Is a child born abroad to a US citizen automatically a citizen?
Many children born abroad to a US citizen parent are US citizens from the moment of birth. That happens automatically if the child met the requirements of INA § 301 or § 309 on the day of birth. No application creates that citizenship. A Consular Report of Birth Abroad, a passport or a Certificate of Citizenship only proves it.
Three facts decide the question. First, whether one or both parents were US citizens at the time of the birth. Second, whether the parents were married to each other. Third, how long the citizen parent had lived or been physically present in the United States before the birth.
The birth date matters as much as the facts. Congress has changed the transmission requirements several times. As a result, USCIS judges a child by the rules in force at birth, not by today’s rules. So a parent who could not pass on citizenship to an older child may pass it on to a younger one, or the other way around.
How long must the citizen parent have lived in the United States?
Take a child born on or after November 14, 1986 to married parents, one a US citizen and one not. Here, the citizen parent must have been physically present in the United States for five years before the birth. At least two of those years must fall after the parent turned 14. Other combinations follow different rules.
| Parents at the time of birth | What the citizen parent must show |
|---|---|
| Both US citizens, married | At least one parent had a residence in the United States before the birth (INA § 301(c)) |
| One US citizen and one US national, married | The citizen parent was physically present for one continuous year before the birth (INA § 301(d)) |
| One US citizen and one noncitizen, married, birth on or after November 14, 1986 | Five years of physical presence, at least two after age 14 (INA § 301(g)) |
| Same, birth before November 14, 1986 | Ten years of physical presence, at least five after age 14 |
| Parents not married | The rules above, plus the additional conditions in INA § 309 |
Physical presence means days actually spent inside the United States, not legal residence or a green card. Time abroad can count in some situations, such as service in the US armed forces. Employment with the US government or certain international organizations also counts. So does time as the unmarried dependent child of someone in one of those roles.
Older births can involve rules that no longer apply to new cases. For example, some once required the child to live in the United States later. Those cases turn on the exact statute in force at the time.
What if the parents were not married?
Children born abroad to unmarried parents can still acquire US citizenship at birth. However, INA § 309 adds conditions. They differ depending on whether the citizen parent is the father or the mother.
A US citizen father
For a child born on or after November 14, 1986, the father has to meet the physical presence requirement. The case also has to show the following.
- Blood relationship A biological relationship between father and child, established by clear and convincing evidence, which sometimes means DNA testing.
- Citizenship at birth The father was a US citizen when the child was born.
- Written support agreement Unless he has died, the father agreed in writing to support the child financially until age 18.
- Legitimation or acknowledgment One of three things happened before the child turned 18. The child was legitimated under the law of the child’s residence or domicile, or the father acknowledged paternity in writing under oath. Otherwise, a court established paternity.
A US citizen mother
In the past, INA § 309(c) let an unmarried citizen mother pass on citizenship after a shorter period of physical presence. The Supreme Court held that difference unconstitutional in Sessions v. Morales-Santana in 2017, and which requirement applies to a particular child now depends on the birth date. Children born through surrogacy or assisted reproduction raise their own questions about which parent counts.
How do you document citizenship for a child born abroad?
Parents of children born abroad document citizenship in one of three ways. The options are a Consular Report of Birth Abroad (Form FS-240) from a US embassy or consulate, a US passport, or a Certificate of Citizenship from USCIS. All three are proof of the same citizenship; they come from different agencies at different stages of life.
- Consular Report of Birth Abroad Issued by the State Department on an application made at the embassy or consulate, usually with a first passport. It is available only before the child turns 18.
- US passport Also issued by the State Department, at any age, on proof of citizenship. You have to renew it.
- Certificate of Citizenship Issued by USCIS on Form N-600 to a person in the United States, at any age. It does not expire.
Registering a birth at the embassy soon after it happens is simpler than rebuilding the evidence later. Twenty years on, schools have discarded records and employers have closed. The Certificate of Citizenship page covers the N-600 route in detail.
What if the child moves to the United States later?
A child who acquired citizenship at birth travels to the United States as a citizen, on a US passport. No immigrant visa is needed. Otherwise, a child who did not acquire citizenship at birth can often become a citizen after moving here, under INA § 320.
Section 320 applies when a child under 18 is a lawful permanent resident with at least one US citizen parent. The child must also live in the United States in that parent’s legal and physical custody. Citizenship follows automatically the moment the child meets the last of those conditions. The green card usually comes through a parent’s immigrant petition, described on the parent and child petitions page. That case often finishes through an immigrant visa interview abroad.
Adopted children can qualify under § 320 too, if the adoption meets the definitions in the Immigration and Nationality Act. Some families discover years later that a child who entered on a green card had in fact been a citizen from birth. In that case, the task is simply to document what already existed.
Can a child who lives abroad become a citizen without moving?
A child who lives outside the United States, and did not acquire citizenship at birth, can apply under INA § 322 on Form N-600K without immigrating. The process has strict conditions and has to finish before the child turns 18.
- Eligibility The child is under 18, has at least one US citizen parent, and lives abroad in that parent’s legal and physical custody.
- Physical presence The citizen parent was physically present in the United States for five years, at least two after age 14. Alternatively, a US citizen grandparent of the child meets that requirement instead.
- Filing The parent files Form N-600K with USCIS and asks for the interview at a particular field office.
- Travel and interview The child comes to the United States on a lawful temporary admission, such as a visitor visa. The child keeps that status for the interview.
- Oath Before turning 18, the child takes the Oath of Allegiance and receives a Certificate of Citizenship. USCIS can waive the oath for a young child.
What goes wrong in children-born-abroad cases?
Most problems come from evidence rather than eligibility: the parent qualified, but cannot now prove it. The others come from applying the wrong version of the law or missing an age deadline.
- Thin physical presence evidence A parent who grew up in the United States but left young may have years of presence. Yet that parent may hold very few documents to show it.
- Counting presence after the birth Only time before the child was born counts toward acquisition at birth.
- Legitimation not completed For a child of an unmarried citizen father, a missing acknowledgment or support agreement before age 18 can defeat the claim.
- Turning 18 The Consular Report of Birth Abroad and the N-600K route both close at 18. Derivation under § 320 also requires the child to meet the conditions before then.
A US passport issued to a child does not settle the question forever. If the underlying facts were wrong, the State Department can later revoke it. Evidence assembled carefully at the start protects the child later.
What does a children-born-abroad matter cost?
We quote a citizenship matter for children born abroad as a flat fee, agreed in writing before any work begins. The same applies whether it leads to a Consular Report of Birth Abroad, an N-600 or an N-600K. USCIS or the State Department sets government filing fees, and you pay them separately, directly to the government.
The first consultation is free and takes about thirty minutes, in person or by phone or video. Our fees and consultations page explains the rest. For the other matters, see the citizenship and naturalization overview.