Families usually think of Portuguese citizenship as something for the applicant, but children are part of the picture too. The rules depend on whether your child was born before or after you became Portuguese, and, since 19 May 2026, they also differ depending on whether the child was born in Portugal to foreign parents. This guide explains the main situations in plain terms and flags where the 2026 changes matter.
Important: This article is general information for educational purposes, not legal advice. Portuguese nationality law is detailed and changed substantially in 2026, and any individual case depends on its particular facts. The position described here is current as of October 2026. Always verify your situation with the Portuguese authorities (the IRN, Instituto dos Registos e do Notariado, and the Conservatória dos Registos Centrais) or a qualified professional before acting.
Children born after you are Portuguese
If you are a Portuguese citizen and your child is born abroad, the child can be Portuguese from birth, provided the birth is registered in the Portuguese civil registry. That is why registering births abroad is such a routine step for Portuguese families, and it is covered in our guide to citizenship through a parent. If you obtained your citizenship by descent or declaration, check that your own registration is complete before the child’s birth is registered.
Not sure where to start with your Portuguese ancestry?
Get the Portuguese Genealogy Quick-Start Checklist — a 5-step path to your first real ancestor record, plus the two-surname naming system that trips up almost every beginner.
Children born before you became Portuguese
This is the situation that surprises families. Citizenship is not automatically extended to a child who was already born when you acquired nationality. Instead, a child under 18, or an adult who needs accompaniment, whose parent acquires Portuguese nationality after the child’s birth, may acquire it by a declaration. A few points follow from the law as described by commentators:
- The declaration is signed by the child’s legal representatives, in principle the parents, who may act through an attorney.
- The child’s ID and the parent’s registration of nationality are part of the file, along with proof of the foreign nationality and a certified translation where needed.
- An effective connection to the Portuguese community has to be shown, and school or vaccination records have been mentioned as the kind of evidence used.
- The authorities can oppose the declaration on grounds that include the absence of an effective connection.
How effective connection is proven for a child
Commentators say that the connection is generally treated as shown where, for example, the child has lived legally in Portugal for at least five years, a parent holds a valid residence permit, or the child has gone through school in Portugal. For a family abroad, this is the hard part: a child who has never lived in Portugal may find it harder to show a connection. If your family is considering a move, the timing of a child’s school years in Portugal can matter. Because the 2026 regulation that should define proof in detail has not yet been published as far as we can tell, check the current position (see the still-pending nationality regulation).
Babies born in Portugal to foreign parents
The rules for a child born in Portugal to foreign parents became stricter on 19 May 2026. Before that date, a child could be Portuguese from birth if one parent had lived in Portugal for just one year. Since then, commentators say at least one parent must have lived legally in Portugal for five years at the time of the birth. Applications already submitted before 19 May 2026 are still decided under the earlier rules, but a family that never made the declaration should not assume the old one-year rule still works for them.
A child who is not Portuguese at birth is not without options. Commentators say a minor born in Portugal can apply for naturalisation once a parent reaches five years of legal residence, provided the child is attending compulsory school, and a child can also acquire nationality through a parent who later becomes Portuguese.
Think you may qualify? Start with our citizenship guide, then build your document chain with the requirements and process article. Verify specifics with the IRN or a qualified adviser.
A worked example (an illustrative composite)
The following is an illustrative composite, not a real family. A mother in Massachusetts becomes Portuguese through her grandmother. Her son, born before she acquired nationality, is 12. Her daughter, born after, is a newborn. The newborn’s birth is registered in the Portuguese civil registry and she is Portuguese from birth. The son is a different case: because he was born before his mother acquired nationality, he can acquire it by a declaration signed by his parents, but he will need to show an effective connection to the Portuguese community. If the family waits until he is 18, he will have to apply in his own right. The difference between the two children is the date of their birth relative to the mother’s acquisition, and that is why the order of events matters.
When a child later wants to claim on their own
If a child reaches 18 before the declaration is made, they would generally apply in their own right and meet the conditions that apply to an adult applicant on that route, including any language requirement. That is why, for many families, the practical advice is to plan the declaration while a child is still a minor. Our guides to the grandparent route and the parent route explain what adults must show on each.
Practical checklist
- List each child’s birth date and compare it with the date you acquire nationality.
- Register births of children born after through the Portuguese civil registry as soon as possible.
- For older children, plan the declaration while they are still minors.
- Gather evidence of connection, such as school and health records, if the route requires it.
- If you plan to live in Portugal, think about the child’s schooling and residence.
For the general picture of what each route requires, see our guide to Portuguese citizenship by descent, and for records, see how to order Portuguese records from abroad.
