I. Plain-English overview

In the Philippines, a child’s surname follows legal filiation and the civil-registry record, not day-to-day preference. If the birth certificate shows the father’s surname, changing it to the mother’s surname is not a clerical edit—it usually needs a court order (unless you undo the legal basis for the father’s surname, e.g., cancel a flawed acknowledgment or prove non-paternity). This guide explains who may change, when, how, and the documents you’ll need—covering both illegitimate and legitimate children.

II. Surnames by default (why your child has the father’s surname now)

Illegitimate child (parents not married at birth)
- Default: uses the mother’s surname.
- Exception: upon the father’s voluntary acknowledgment (e.g., Affidavit of Admission/Recognition of Paternity or his signing the birth certificate) and the mother’s consent when required, the child may use the father’s surname. This is how many children end up carrying the father’s surname despite being illegitimate.
Legitimate child (parents married at birth or later legitimated)
- Default: uses the father’s surname by operation of law (unless changed later by court on compelling grounds).

Key point: Once the father’s surname is on the PSA birth certificate through a valid legal act, reverting to the mother’s surname is not automatic even if parents separate, annul, or the father stops supporting the child.

III. The three lawful pathways to change from father → mother

Path A — Judicial Change of Name (Rule 103)

When used: The father’s acknowledgment is valid and paternity is not in dispute, but you want the child to carry the mother’s surname for best-interest reasons (e.g., abandonment, non-support, safety/VAWC context, bullying, long-term use of mother’s surname, identity consistency).
Who files:
- If the child is a minor: the mother (or legal guardian) files as guardian ad litem.
- If the child is 18+: the child files personally.
What to prove: “Proper and reasonable cause” / best interests of the child, not mere convenience. Courts weigh: parental authority (for illegitimate children, mother’s sole authority), history of care/support, risk of confusion, child’s wishes (especially if of discernment), school/community usage, and harm/trauma concerns.
Outcome: Court grants a change of surname from father to mother. After finality, the LCR and PSA annotate the birth record.

Path B — Cancellation/Correction of Civil Registry Entry (Rule 108)

When used: The father’s surname appears because of a defective or void basis, e.g.:
- forged or coerced acknowledgment;
- acknowledgment without legal capacity (e.g., minor/fraud);
- subsequent DNA or judgment disproves paternity;
- the entry was erroneous (not mere misspelling but a substantive mistake).
What happens: You ask the court to cancel the acknowledgment/annotation or correct the entry. If paternity is set aside, the child reverts by law to the mother’s surname (no separate Rule 103 petition needed).

Path C — Status-changing proceedings that automatically drive a surname change

Adoption: If the child is adopted (e.g., by the mother’s new spouse), the child typically takes the adopter’s surname (not the mother’s maiden name).
Legitimation/Nullity/Annulment/Divorce recognition: These affect status but do not automatically change a child’s surname from father to mother. You still need Path A or B unless the legal basis for the father’s surname is extinguished.

Not available administratively: RA 9048/10172 (administrative correction) does not allow changing surnames (except clerical/typographical errors). A father→mother change is substantive and needs the court unless you’re undoing an invalid acknowledgment under Path B.

IV. Strategy by scenario (choose the track that fits)

Scenario 1 — Illegitimate child uses father’s surname via valid acknowledgment; paternity is not disputed

Use Path A (Rule 103). Build a best-interest dossier:
- Mother’s sole parental authority (default for illegitimate children);
- Non-support, abandonment, or safety concerns (attach proofs: demands, chats, police reports, VAWC orders where applicable);
- Child’s consistent use of mother’s surname in school/medical records;
- Psychosocial impact statements (guidance counselor/psychologist);
- Affidavits of caregivers/teachers on confusion or harm.
Child’s consent: If the child is of discernment (often 7+), courts value the child’s express preference.

Scenario 2 — The acknowledgment is defective or paternity is false

Use Path B (Rule 108) to cancel the acknowledgment or correct the entry. Support with:
- DNA results or compelling proof of non-paternity;
- Evidence of fraud, duress, or forgery;
- Proof of legal incapacity when the acknowledgment was executed.
Once granted, PSA reverts the surname to the mother’s without a Rule 103 case.

Scenario 3 — Legitimate child (parents married) seeks mother’s surname

This is harder, but possible via Path A (Rule 103) upon showing exceptional, child-centered reasons (identity continuity with custodial mother, long separation, compelling welfare concerns). Courts will not grant it for convenience or to sever the father-child legal link.

V. Step-by-step procedure (for Path A or B)

Hire counsel (recommended): These are special civil actions with publication and notice requirements.
Gather evidence:
- PSA documents: Birth Certificate (SECPA), parents’ civil status records (marriage certificate if any), acknowledgment/Affidavit that placed the father’s surname, and any PSA annotations.
- Best-interest proofs: school records, medical files, counseling notes, barangay/police reports, VAWC orders, affidavits.
- Non-paternity proofs (for Path B): DNA, expert reports, exemplars.
File Petition in the RTC where the civil registry record is kept or where the petitioner resides (venue rules apply).
Publication & notice: The court orders publication in a newspaper of general circulation and notifies the LCR, PSA, and interested parties (including the father).
Hearing: Present testimonial and documentary evidence; if feasible, the child may be heard (in chambers) on preference and welfare.
Decision: If granted, obtain Entry of Judgment after finality.
Civil registry implementation:
- File certified copies with the LCR of the place of registration.
- LCR endorses to PSA for annotation of the birth certificate.
Update downstream records: school, PhilHealth, passports, bank, vaccinations, SSS/GSIS (if any), and LGU IDs. Bring the PSA-annotated birth certificate.

VI. Evidentiary tips that move courts

Continuity & identity: Show long, consistent use of the mother’s surname in daily life (IDs, school nameplates, clinic records).
Welfare impact: Detail stigma/bullying, safety risks (e.g., if the father is a VAWC respondent), or administrative burdens (travel consent/confusion).
Parental roles: Document who actually cares and pays for the child; courts look at substance over labels.
Good faith: Make clear the petition is not to erase filiation or deny support; the change is to protect the child’s welfare and identity.

VII. FAQs

Q1: We’re separated/annulled. Does the child automatically switch to my (mother’s) surname? No. Marital breakup does not change a child’s surname. You still need Path A (Rule 103) or Path B (prove a defective recognition/non-paternity).

Q2: Can I do this at the LCR under RA 9048 or 10172? Generally no—those laws cover first names, clerical errors, and specific birth-date/sex corrections. Surname changes are substantive and usually judicial.

Q3: The father never supported us. Is that enough? It helps, but courts still assess the child’s best interests holistically (identity, safety, stability). Combine non-support evidence with welfare and usage proofs.

Q4: Will changing the surname cut the father’s support or inheritance duties? No. Surname choice does not alter filiation. If paternity remains recognized, the child keeps the right to support and succession.

Q5: Can the father block the petition? He may oppose. The court will weigh both sides, but the decisive standard is the child’s best interests and the strength of your evidence.

Q6: My child is already 18. Can they file? Yes. An adult child can personally petition to adopt the mother’s surname, explaining proper and reasonable cause.

Q7: Do I need DNA? Only if you’re claiming non-paternity (Path B). For best-interest changes (Path A), DNA is not required.

VIII. Special notes

Parental authority: For illegitimate children, the mother has sole parental authority unless a court orders otherwise—this supports mother-led petitions.
Child’s voice: Courts increasingly credit the child’s own preference, especially when the child is of school age and can articulate reasons.
Muslim/indigenous personal laws: Customary norms on filiation/naming may apply alongside national statutes; consult counsel familiar with these regimes.

IX. Model petition outline (for guidance only)

Parties & jurisdiction/venue
Facts (birth details, current PSA entries, how the father’s surname got in)
Grounds
- Path A: Best interests (detail welfare, usage, confusion, safety)
- Path B: Defective acknowledgment / non-paternity (attach proofs)
Reliefs sought
- Change/cancellation; directive to LCR/PSA to annotate records
Prayer for publication/notice
Annexes: PSA docs, affidavits, school/medical/counseling records, DNA (if applicable)

X. After the grant—clean-up checklist

☐ Secure Entry of Judgment and certified decision
☐ File with LCR; get PSA-annotated birth certificate
☐ Update school, PhilHealth, passport/DFA, bank/e-wallet, vaccination, LGU ID, SSS/GSIS (if any)
☐ Keep both old and annotated PSA copies for cross-reference during transitions

XI. Key takeaways

Changing a child’s surname from father → mother is legally doable, but it’s not administrative; expect a court process unless you’re canceling a defective recognition.
Choose Path A (Rule 103) for best-interest reasons, or Path B (Rule 108) if the father’s acknowledgment is invalid or paternity is disproved.
The change does not affect filiation or support rights—only the surname label.
Strong, child-centered evidence—identity continuity, welfare, safety, non-support, child’s preference—wins petitions.
After judgment, follow through with LCR/PSA annotation and update the child’s everyday records to avoid confusion.

If you want, tell me your child’s current PSA entries (illegitimate/legitimate; how the father’s surname got on record; child’s age; any safety/non-support issues), and I’ll map the faster viable path and a document checklist tailored to your case.