Changing a minor child’s surname in the Philippines is strictly regulated because the surname is a fundamental marker of filiation, family identity, and legal status under the Family Code and civil registration laws. Arbitrary changes are not permitted only on grounds expressly allowed by law. Any change must result in either an annotated Certificate of Live Birth (COLB) or an entirely new birth certificate, and the process is never done by mere private agreement or notarized deed alone.

There are five legally recognized ways to change a minor child’s surname:

Administrative correction of clerical or typographical error (Republic Act No. 9048, as amended by RA 10172)
Use of the father’s surname by an illegitimate child (Republic Act No. 9255)
Automatic change upon legitimation by subsequent marriage of parents (Arts. 177–182, Family Code)
Change upon adoption (RA 8552 – Domestic Adoption Act; RA 8043 – Inter-Country Adoption Act)
Judicial change of name under Rule 103, Rules of Court (only on very limited grounds)

Below is a complete, updated (as of November 2025) guide to each method.

1. Administrative Correction of Clerical or Typographical Error

(RA 9048 as amended by RA 10172)

Applicable when:
The surname on the birth certificate is wrong due to a clear clerical or typographical error (e.g., “Santos” misspelled as “Santus,” “Dela Cruz” written as “De La Cruz” without justification, or the child’s surname was mistakenly entered as the mother’s when it should have been the father’s because the child is legitimate).

Not applicable when:
The requested change is substantial (e.g., from mother’s surname to father’s surname because the child was originally registered as illegitimate but is actually legitimate, or because the father now wants to acknowledge the child — these fall under RA 9255 or court petition).

Who may file:

Both parents jointly, or
The surviving parent, or
The guardian (with Special Power of Attorney if abroad), or
The child himself/herself if already 18 years old at the time of filing.

Where to file:

City/Municipal Civil Registrar (C/MCR) of the place where the birth is registered, or
Philippine Consulate/Embassy if the birth is registered abroad (Consularized Record).

Requirements (2025):

Certified true copy of the Certificate of Live Birth (PSA-authenticated)
At least two (2) public or private documents showing the correct surname (e.g., baptismal certificate, school records, medical records, immunization card)
Affidavit of Explanation (notarized)
NBI clearance of petitioner(s)
Police clearance (if petitioner is resident of the city/municipality)
Proof of payment of fees (approx. ₱3,000 for correction of surname + ₱1,000 publication fee if required)
For minors: joint affidavit of both parents or court-appointed guardian

Procedure:

File petition with the C/MCR
10-day posting period
If no opposition, decision is rendered within 30–60 days
Annotation is made on the original COLB; PSA issues annotated copy

Processing time: 2–4 months in practice (longer if abroad).
Cost: ₱3,000–₱5,000 total depending on the local government unit.

2. Use of Father’s Surname by Illegitimate Child

(Republic Act No. 9255 – “An Act Allowing Illegitimate Children to Use the Surname of Their Father”)

This is the most common reason for changing a minor’s surname.

Applicable when:

Child was registered as illegitimate (using mother’s surname)
Father now executes an Affidavit to Use the Surname of the Father (AUSF) or the recognition appears in a public document or private handwritten instrument signed by the father

Two scenarios:

A. At the time of birth registration – AUSF is attached to the COLB; child is immediately registered with father’s surname.
B. After birth registration – Child is already using mother’s surname; father now wants child to use his surname.

Procedure for Scenario B (change after registration):

Father executes a notarized Affidavit to Use the Surname of the Father (AUSF)
If the father is abroad, the AUSF must be consularized or apostilled
Mother must give consent (usually executed in the same instrument or separately)
File the AUSF together with the PSA-authenticated COLB at the C/MCR where the birth is registered
Pay registration fee (₱1,000–₱2,000)
The civil registrar shall annotate the COLB: “The child is now authorized to use the surname of the father pursuant to RA 9255”
PSA will issue a new COLB bearing the father’s surname

Important notes:

The mother’s consent is required if the child is below 7 years old.
From age 7–17, the child’s written consent is also required.
At 18, the child may execute the AUSF himself/herself even without parents’ consent.
This is administrative, not judicial — no court order needed.

3. Change upon Legitimation by Subsequent Marriage

When the biological parents of an illegitimate child marry each other, the child becomes legitimate and automatically entitled to the father’s surname.

Procedure:

Parents marry (submit marriage certificate to C/MCR)
Execute Joint Affidavit of Legitimation (notarized)
File at the C/MCR where the child’s birth is registered
C/MCR issues a new Certificate of Live Birth showing:
- Status: “Legitimate”
- Surname: Father’s surname
- Parents: “Married on [date]”

Cost: ₱2,000–₱3,000
Time: 1–3 months

4. Change upon Adoption

Domestic Adoption (RA 8552):
The adopted child’s new COLB will bear the adopter(s)’ surname. The original birth certificate is sealed forever.

Inter-country Adoption (RA 8043): Same effect.

The change is automatic upon issuance of the Decree of Adoption and the amended birth certificate by PSA.

5. Judicial Change of Name (Rule 103, Rules of Court)

This is the last resort and is rarely granted for minors unless extremely compelling.

Valid grounds for a minor (as consistently ruled by the Supreme Court):

The surname is ridiculous or dishonorable
The change is necessary to avoid confusion
The child has been known by another surname since childhood (e.g., raised by stepfather and uses his surname informally)
The change is a legal consequence of legitimation or adoption (but these now have separate procedures above)
The surname causes extreme prejudice or embarrassment

Grounds almost always rejected for minors:

“I just don’t like the surname”
“The father abandoned us, I want to drop his surname” (Supreme Court has repeatedly ruled that abandonment is not a ground to change surname; filiation cannot be erased)
Wanting to use stepfather’s surname without adoption (not allowed)

Who may file:

Both parents (or surviving parent)
Guardian with court authority
The minor himself/herself if at least 14 years old (with parental consent)

Where to file: Regional Trial Court (RTC) of the province/city where the petitioner resides (family court branch if available).

Requirements:

Verified petition stating grounds
PSA birth certificate
Affidavits of at least two disinterested persons
NBI clearance, police clearance, barangay clearance
Proof of publication of the petition and hearing date in a newspaper of general circulation for three consecutive weeks
For minors: school records, baptismal certificate, etc.

Procedure:

File petition
Court orders publication (3 weeks)
Hearing (OSG and local civil registrar notified)
If approved, court issues Order
Order is registered with the C/MCR
PSA issues new birth certificate

Success rate for minors: Very low unless the ground is exceptionally strong (e.g., surname is “Hitler,” “Bin Laden,” or similar cases that have been granted).

Cost: ₱150,000–₱300,000 including publication and lawyer’s fees.
Time: 1–3 years.

Summary Table of Options

Method	Ground Required	Venue	Court Needed?	Typical Cost	Typical Time
RA 9048 (clerical error)	Typographical error	Local Civil Registrar	No	₱3,000–₱5,000	2–4 months
RA 9255 (illegitimate → father’s surname)	Father’s recognition/AUSF	Local Civil Registrar	No	₱1,000–₱2,000	1–3 months
Legitimation	Parents subsequently marry	Local Civil Registrar	No	₱2,000–₱3,000	1–3 months
Adoption	Decree of Adoption	Local Civil Registrar	Yes (adoption case)	Part of adoption cost	6–24 months
Rule 103 (judicial)	Compelling legal ground	Regional Trial Court	Yes	₱150k–₱300k	1–3 years

Final Notes

A child below 7 years old has no legal capacity to choose his/her own surname; the law decides for him/her.
From 7–17 years old, the child’s consent is required in RA 9255 cases and is given weight in Rule 103 petitions.
Once a child reaches 18, he/she may file for change of surname with much broader (though still limited) grounds.
Abandonment, hatred toward the father, or preference for the stepfather are not valid grounds to drop the biological father’s surname while the child is still a minor.

This constitutes the complete legal framework for changing a minor’s surname in the Philippines as of November 2025. Always consult a lawyer for the particular circumstances of the child, as factual nuances can dramatically affect which procedure is proper.