Can a child use father's surname?

Can a Child Use the Father’s Surname?

Yes, a child can use the father’s surname—even if born outside of marriage—provided the father voluntarily acknowledges the child. Under Republic Act No. 9255, also known as the "Act Allowing Illegitimate Children to Use the Surname of Their Father," a child can legally bear the father’s last name if the father executes an affidavit of recognition or another valid public document acknowledging paternity.

This law was a significant step toward fairness for children in the Philippines, ensuring that paternal recognition isn’t blocked solely due to the parents’ civil status. It’s important to note, however, that using the father’s surname does not automatically legitimize the child under Philippine law. Legitimacy is tied to the parents’ marital status at the time of birth and carries additional legal implications—such as inheritance rights—that are not granted simply by using the father’s surname.

The process is straightforward: the father must execute a formal acknowledgment, typically attached to the child’s birth certificate during registration or through a legal amendment if the birth was already registered. This document must be filed with the Local Civil Registry or the Philippine Statistics Authority (PSA).

While emotional and social stigmas around family structure still exist, laws like R.A. 9255 reflect a growing recognition of a child’s right to identity and connection with both parents. For many, having the father’s surname is more than a legal formality—it’s a meaningful affirmation of belonging.