Can an Illegitimate Child Use the Surname of His Father?

Yes, if the child was born before August 3, 1988 or born on March 19, 2004 onwards.

The Civil Code of the Philippines (which governs births before the effectivity of the Family Code) provides that the child shall use the surname of the father so long as the child is acknowledged by both parents.

For births that occur on March 19, 2004 onwards, an illegitimate child can use the surname of the father provided an Affidavit to Use the Surname (AUSF) is executed.

Please note that the AUSF is executed not by the father but by the mother if the child is 6 years old and below; by the child himself attested by the mother or guardian if the child is 7 years old to 17 years old; and the person himself without the mother or guardian’s attestation, if the person is 18 years old above.

However, just because an illegitimate child is qualified to use his father’s surname doesn’t mean he can’t refuse it.

According to Art. 176 of the Family Code as amended by RA 9255, a father can’t compel or force his illegitimate child to use his surname. 

It reads:

“Article 176. … illegitimate children may use the surname of their father if their filiation has been expressly recognized by the father through the record of birth appearing in the civil register, or when an admission in a public document or private handwritten instrument is made by the father.”

In the case of Grande vs. Antonio, G.R. No. 206248, the Supreme Court ruled that the right to decide whether an illegitimate child will use the surname of the father is lodged with the child – and not with the father. This is because Art. 176 of the Family Code, as amended by RA 9255, uses the word “may”.

“The use of the word ‘may’ in the provision readily shows that an acknowledged illegitimate child is under no compulsion to use the surname of his illegitimate father. The word ‘may’ is permissive and operates to confer discretion upon the illegitimate children.”

Go back to the main article: An Ultimate Guide to an Illegitimate Child’s Rights, Birth Registration, and Legitimization