Using the Mother’s Surname for Children in the Philippines: RA 9255 and Name-Change Rules

1) Why surnames matter in Philippine law

In the Philippines, a child’s surname affects identity, filiation, inheritance, travel documents, school and medical records, and a host of civil-status questions. The rules are largely found in the Family Code, Republic Act (RA) No. 9255 (and its IRR), the Civil Registry Law and its administrative issuances, and the Rules of Court for judicial name changes. This article maps the full landscape—centered on the use of the mother’s surname—then situates RA 9255 within it.

2) Baseline rule: whose surname does a child carry?

A. Legitimate child (parents married to each other at the time of birth)

Default surname: the father’s surname (Family Code, Arts. 174–175).
Using the mother’s surname instead is not automatic but may be allowed by a court through a Rule 103 petition (see §8), if the court finds proper and reasonable cause (jurisprudence recognizes maternal-surname changes on compelling facts such as abandonment, estrangement, potential harm, or long-settled usage).

B. Illegitimate child (parents not married to each other at the time of birth)

Default surname: the mother’s surname (Family Code, Art. 176, as amended).
This default reflects the law’s baseline identification of the mother as the known parent at birth.

3) Where RA 9255 fits—and what it actually changed

RA 9255 (effective 2004) did not require illegitimate children to use the father’s surname. Instead, it created an option: an illegitimate child may use the father’s surname if the father voluntarily acknowledges the child and the required documents are executed and recorded with the civil registrar.

Key points:

If no valid acknowledgment + no valid request to use the father’s surname, the child keeps the mother’s surname—full stop.
RA 9255 does not take away a child’s right to continue using the mother’s surname even if the father later acknowledges paternity; the statute merely opens the door to switch to the father’s surname if the legal steps are followed.

4) How illegitimate children use the father’s surname under RA 9255 (for contrast)

To understand when a child keeps the mother’s surname, it helps to know when the child can lawfully switch:

Prerequisites

Acknowledgment of paternity by the father via any of the instruments recognized by the IRR:
- Affidavit of Admission of Paternity (AAP) executed by the father; or
- A private handwritten instrument or other document clearly acknowledging paternity; or
- A court judgment establishing filiation.
Affidavit to Use the Surname of the Father (AUSF):
- If child is below 7: the mother executes the AUSF on the child’s behalf.
- If 7 to below 18: the mother and the child (with the child’s consent) sign.
- If 18 or above: the child personally executes the AUSF.

Registration & annotation

The LCRO/PSA annotates the child’s birth record to reflect use of the father’s surname.
Without the above documents, the registrar cannot change the surname administratively.

Middle name note

As a matter of registration practice, an illegitimate child does not acquire the father’s middle name even when using the father’s surname under RA 9255. (Middle-name formatting for illegitimate children has been treated conservatively by civil registrars; expect local practice to be strict.)

5) Keeping the mother’s surname: common scenarios

Illegitimate child, no paternal acknowledgment or AUSF
- Child retains the mother’s surname indefinitely.
Illegitimate child, father acknowledged paternity but no AUSF filed
- Acknowledgment alone does not change the surname; the child continues using the mother’s surname unless an AUSF is validly executed and annotated.
Illegitimate child originally using mother’s surname, later wants to adopt father’s surname
- Follow RA 9255 steps in §4. Before completion, the child still uses the mother’s surname.
Illegitimate child already using father’s surname wants to revert to mother’s surname
- RA 9255 does not provide a “toggle back” form. Reversion generally requires a judicial petition for change of name under Rule 103 (see §8), showing proper and reasonable cause. Civil registrars typically cannot undo an AUSF via clerical-error proceedings.
Legitimation by subsequent marriage of the parents
- Legitimation (Family Code) transforms the child’s status; surname rules follow legitimation, typically resulting in the father’s surname. If the family wishes the mother’s surname post-legitimation, that usually requires judicial relief.
Adoption
- Adoption carries its own surname rules; administrative corrections or amendments in adoption decrees are not substitutes for Rule 103 petitions when seeking a maternal-surname outcome at odds with the default rule.

6) Birth-certificate errors vs. true name changes

It’s critical to separate clerical corrections from substantive changes:

RA 9048 (Clerical Error Law) as amended by RA 10172 allows administrative correction of:
- Clerical/typographical errors;
- Change of first name or nickname;
- Correction of day/month of birth and sex when due to clerical error.
But RA 9048/10172 does not allow administrative changes of surnames (except where a special law expressly allows it—e.g., RA 9255 via AUSF annotation, or amendments flowing from adoption/legitimation orders).
Wrongly-entered surnames (e.g., registrar mistakenly typed the father’s surname despite no basis) may be corrected administratively as a clerical error if documentary evidence proves the mistake. This is not a discretionary “change”; it is a correction to conform the record to facts/law.

7) Practical steps to ensure (and defend) the mother’s surname

A. At or soon after birth (illegitimate child):

Ensure the Certificate of Live Birth (COLB) lists the mother’s surname as the child’s surname.
Do not sign, or allow to be filed, any AUSF unless you intend to adopt the father’s surname.

B. If the father later acknowledges paternity but you prefer the mother’s surname:

Simply do not file an AUSF. The acknowledgment alone won’t change the surname.
If a registrar annotated the father’s surname without a valid AUSF, you may pursue administrative correction for lack of basis, or judicial relief if contested.

C. If records are inconsistent (e.g., school IDs vs. PSA copy):

Align them to the PSA birth certificate. Where a clerical mistake exists in the PSA entry, use RA 9048 correction; where a conscious change is sought, consider Rule 103.

D. Travel & passports:

The passport must match the PSA record (or the annotated record). If the child’s daily life uses the mother’s surname but the PSA has already been annotated to the father’s surname, you’ll need to address the record first before DFA issuance/renewal to avoid mismatches.

8) Judicial change of surname to the mother’s surname (Rule 103 primer)

When the law’s default (e.g., father’s surname for legitimate children, or a completed AUSF for an illegitimate child) is already in place, a court petition under Rule 103 may be used to change the surname to the mother’s surname.

Essentials:

Venue: Regional Trial Court where the petitioner resides.
Parties: The child (represented by the mother/guardian if a minor) is the petitioner; the Civil Registrar and Office of the Solicitor General/City Prosecutor typically appear to represent the State’s interest in the stability of names.
Standard: Courts require “proper and reasonable cause.” Factors may include: long and exclusive use of the mother’s surname, estrangement or abandonment by the father, risk of confusion or harm, best interests of the child, and substantial identity interests (e.g., all siblings carry the mother’s surname).
Effect: A granted petition results in a court order directing the LCRO/PSA to annotate the change.

Good practice for success:

Show consistent usage of the mother’s surname in school, medical, and community records;
Present clear reasons tied to the child’s welfare, not mere personal preference;
Include the father’s stance (notice and opportunity to be heard), or document failed efforts to locate him.

9) Special issues & frequently misunderstood points

Acknowledgment ≠ automatic change. AAP or filiation proof alone does not switch the surname; the AUSF (or a court order) does.
You generally cannot “undo” an AUSF at the civil registrar. Once properly executed and annotated, reverting to the mother’s surname typically needs a Rule 103 petition (unless the original annotation is legally defective).
Middle name rules are conservative. For illegitimate children, civil registrars usually do not allow carrying the father’s middle name—even when the child uses the father’s surname under RA 9255. Expect the middle name field to be blank (or, depending on local practice, to reflect conservative formatting).
Subsequent marriage (legitimation) changes the legal landscape. After legitimation, the surname rules align with legitimate-child rules. If a maternal surname is still desired, you’re looking at Rule 103.
Administrative vs. judicial paths.
- Administrative: clerical correction (RA 9048/10172) or AUSF (RA 9255).
- Judicial: Rule 103 (change of name) and court-driven amendments (adoption, filiation judgments).

10) Document checklists (practical, not exhaustive)

If the child will keep the mother’s surname

PSA/LCRO Certificate of Live Birth showing mother’s surname.
If the father later acknowledged paternity but you never filed an AUSF, keep copies of any AAP/acknowledgment to show why the child still uses the mother’s surname (i.e., acknowledgment does not force a change).

If the child accidentally carried the father’s surname without legal basis

Evidence showing no AUSF was executed and the father’s surname entry was a clerical mistake or premature annotation → pursue RA 9048 correction.

If the child wants to change to the mother’s surname but records already show the father’s surname

Prepare for Rule 103:
- Proof of residence;
- PSA birth record;
- IDs and records showing long-time use of the mother’s surname (if applicable);
- Evidence of best interests (e.g., siblings’ surnames, social identity, absence/abandonment facts, safety concerns);
- Proof of notice to the father and the civil registrar.

11) Strategy guide by life stage

Infancy/early childhood: Lock in the mother’s surname at registration unless and until a deliberate decision is made to use the father’s surname via RA 9255.
School age: Keep all records (school, health, benefits) aligned with the PSA entry to avoid passport/visa issues later.
Age 7–17: The child’s consent is needed for AUSF; if the family prefers the mother’s surname, do not sign AUSF.
Age 18+: The child personally decides on AUSF (to adopt the father’s surname) or may pursue Rule 103 to move to the mother’s surname if records show the father’s surname.

12) Quick answers to common questions

Q: My child is illegitimate. We want the mother’s surname. Do we need to file anything? A: No. The default is the mother’s surname. Just register that way.
Q: The father signed an AAP later. Will the surname change automatically? A: No. It changes only if an AUSF is validly executed and annotated.
Q: Can we switch back to the mother’s surname after filing an AUSF? A: Not administratively. You generally need a Rule 103 petition and a court order.
Q: We are married (legitimate child) but the child has always used the mother’s surname at school. Can we formalize it? A: Possibly via Rule 103, if you can show proper and reasonable cause and it’s in the child’s best interests.
Q: The birth certificate shows the father’s surname but we never signed AUSF and we weren’t married. What now? A: That looks like a clerical/registrar error. Explore RA 9048 correction to restore the mother’s surname.

13) Takeaways

For illegitimate children, the law’s starting and staying point is the mother’s surname, unless RA 9255 is affirmatively used.
RA 9255 is permissive, not mandatory; it enables (but does not force) use of the father’s surname.
Administrative remedies handle clerical issues and RA 9255 annotations; judicial remedies (Rule 103) handle true changes—including shifts to the mother’s surname when the default or a prior annotation stands in the way.
Align all records to the PSA entry before travel, school transitions, or major applications.

Friendly disclaimer

This overview is for general information on Philippine law and civil-registration practice. Specific facts can change outcomes. For live cases—especially contested ones—consult a Philippine lawyer or your local civil registrar for document-level guidance.