Short answer. Under Civil Code Article 364, a legitimate or legitimated child shall principally use the surname of the father. This is the default rule — the child carries the father's family name, and it applies from the time of registration at birth.

What the law says

Legitimate and legitimated children shall principally use the surname of the father.

Civil Code, Article 364 — Surname of Legitimate Children. Read the full provision →

The rule: father's surname as the principal surname

Article 364 states the rule plainly: legitimate and legitimated children shall principally use the surname of the father. The word 'principally' is significant. It establishes the father's surname as primary — the name that appears first, the name by which the child is known — without prohibiting the use of the mother's surname in the middle name position, which is common practice in the Philippines. The rule applies whether the child was born of a valid marriage or was later legitimated because the parents married after the child's birth.

Legitimate versus legitimated children

Article 364 covers two categories. A legitimate child is one born of parents who were validly married at the time of birth or who were conceived before the marriage and born after. A legitimated child is one who was born outside of marriage but whose parents subsequently married and whose legitimation was recognised under the law. Both carry the father's surname under Article 364. The moment of legitimation — typically upon the marriage of the parents — is when the legitimated child acquires the right to the father's surname and the legal status that goes with it.

What 'principally' does not mean

The word 'principally' does not require the child to drop the mother's surname entirely. Philippine naming practice historically places the mother's maiden surname in the middle-name position. Article 364 does not disrupt that. What it does is establish the father's surname as the family name — the last name, the name that identifies the child within the father's line. The child is not free to adopt a different surname entirely, nor can the mother register the child under her own surname in preference to the father's, as long as the child is legitimate.

Changing a child's surname is not straightforward

Because Article 364 sets the father's surname as the child's principal name by operation of law, departing from it requires a formal proceeding. A parent who wishes to have a legitimate child's registered surname changed must file a petition in court or, where permitted by later rules, before the civil registrar. The process is not simply a matter of filing a correction. The legitimacy of the child — and the corresponding right to the father's surname — is a matter of civil status that cannot be altered informally. If you are dealing with a surname dispute for a child, a lawyer can advise on which procedure applies in your specific situation.

Cases citing this provision

These Supreme Court decisions cite the provision above. We list them so you can read them yourself; the summaries of what each decided are not ours to give.

Related provisions

Note. Statute text quoted on this page is reproduced from the official enactment and is linked to the full provision. The explanation around it is general legal information from Vivas & Nobles Law Office, not legal advice. Whether it applies to your situation depends on facts only a lawyer reviewing them can assess.