In the Philippines, “informal adoption” — also referred to as de facto adoption, private adoption arrangement, or simple foster care by relatives — is extremely common. A child is taken in and raised by non-biological parents (usually relatives or close family friends) without any court decree or amended birth certificate. While emotionally and socially the child becomes part of the new family, legally the child remains the child of the biological parents. Consequently, the child’s birth certificate and legal surname remain unchanged.

This creates practical problems: the child uses the adoptive family’s surname in school, in the barangay, and in daily life, but the PSA (Philippine Statistics Authority) birth certificate still reflects the biological parents’ surname. Banks, passport applications, school credentials, and inheritance matters will require the legal surname. The only ways to permanently and legally change the child’s surname to that of the person who has been raising him/her are the following:

1. Formalize the Adoption Through Judicial Adoption (Most Common and Cleanest Solution)

Under Republic Act No. 8552 (Domestic Adoption Act of 1998), as amended, and the Amended Implementing Rules and Regulations (AIRR) issued in 2019, any person who has been taking care of a child for at least three (3) years may file a petition for adoption even if the arrangement began informally.

Key Requirements for Domestic Adoption When the Child Has Been Informally Adopted

Petitioner must be at least 27 years old and at least 16 years older than the adoptee (waivable in certain cases, e.g., when adopting a relative).
Petitioner must have the capacity to act as parent (emotional, moral, financial).
The child must be below 18 years old at the time of filing (if already 18 or above, adoption is no longer possible).
Consent requirements:
- Consent of the biological parents or legal guardian (if they are still alive and have not abandoned the child).
- If biological parents are unknown or have abandoned the child for at least three (3) continuous years, consent may be dispensed with.
- Consent of the child if 10 years old or over.
- Consent of petitioner’s spouse, if married.
Child Study Report and Home Study Report prepared by a licensed social worker (DSWD or accredited agency).
Posting requirement (publication in newspaper of general circulation once a week for three consecutive weeks) is now dispensed with under the AIRR if the petition is for adoption of a relative within the 4th degree of consanguinity or if the child has been in the petitioner’s care for at least three years.
The entire process now takes approximately 6–12 months (much faster than pre-2019).

Effect on Surname

Once the adoption decree becomes final and executory, the law automatically grants the adopted child the right to use the adopter’s surname (Article 189, Family Code; Section 13, RA 8552). The Civil Registrar will issue a new Certificate of Live Birth showing the adopter(s) as the parent(s) and the child bearing the adopter’s surname. The original birth certificate is sealed and becomes confidential.

This is the cleanest and most complete solution because it not only changes the surname but also creates legal filiation: the child becomes a legal heir, entitled to support, inheritance, and all rights of a legitimate child.

2. Rectification of Simulated Birth Under Republic Act No. 11222 (Simulated Birth Rectification Act of 2019)

Before RA 11222, the most common way to “informally adopt” was through simulation of birth — the adoptive parents went to the hospital or local civil registrar and registered the child as if the adoptive mother gave birth to the child. This was technically falsification of public documents but was socially accepted for decades.

RA 11222 decriminalized past simulation of birth and provided an administrative and judicial remedy.

Two Tracks Under RA 11222

A. Administrative Rectification (DSWD) – for cases where the biological parents are known and consent

The person who simulated the birth and the biological parent(s) jointly file an affidavit of admission/acknowledgment with DSWD.
DSWD issues a Certificate of Foundling or Certificate of Child Available for Adoption.
The simulated birth certificate is rectified administratively: the biological parents are restored, and the child is declared legally available for adoption.
The “adoptive” parent may then file for adoption under RA 8552 (fast-tracked).

B. Judicial Rectification (Regional Trial Court – Family Court)

Used when biological parents cannot be located, refuse consent, or have abandoned the child.
The petitioner (person who simulated the birth) files a verified petition.
After hearing and publication, the court issues an order rectifying the birth record and simultaneously granting adoption if the requisites are met.

Effect on Surname

After rectification and adoption, a new birth certificate is issued with the adopter’s surname. This remedy has been widely availed of since 2019; thousands of families have regularized their status this way.

3. Petition for Change of Name Under Rule 103 of the Rules of Court (Rarely Granted for Minors in Informal Adoption Cases)

A pure change-of-name petition (not anchored on adoption) is almost never granted when the purpose is to make the child use the surname of a non-biological parent. The Supreme Court has repeatedly ruled that:

Surname indicates filiation; changing it without legal adoption would violate public policy (Republic v. Lim, G.R. No. 168155, 2005; In re: Petition for Change of Name of Julian Lin Carulasan Wang, G.R. No. 159966, 2005).
Mere long use of the adoptive surname or affection of the foster parent is not sufficient ground.
The petition will be denied if it appears that the real purpose is to establish artificial paternity/maternity.

There are, however, exceptional cases where the Supreme Court has allowed the addition (not substitution) of the maternal surname or the use of the stepfather’s surname when the biological father is completely absent and has never supported the child (Alfon v. Republic, G.R. No. L-21284, October 11, 1968; Republic v. Hernandez, G.R. No. 117209, February 9, 1996). But these are old cases and are applied very restrictively today.

In practice, family courts now almost automatically deny Rule 103 petitions for minors when the obvious intent is informal adoption, and instead advise the petitioner to file adoption.

4. Use of Stepfather’s Surname After Marriage of the Mother (Limited Application)

If the biological mother marries the man who has been raising the child, Article 369 of the Civil Code and Republic Act No. 9255 allow the child to use the stepfather’s surname with the stepfather’s written consent, but this does not change the birth certificate. It is merely authorized use for school and other purposes. The PSA birth certificate remains unchanged, and for legal purposes (passport, inheritance, etc.) the original surname must still be used.

Summary Table: Options Available to Change Child’s Surname After Informal Adoption

Option	Legal Effect on Filiation	Surname Change on PSA Birth Certificate	Time Frame	Success Rate (2020–2025)	Best For
Domestic Adoption (RA 8552)	Full legal child	Yes (new birth certificate)	6–18 months	Very high (>95%)	All cases, especially relatives
RA 11222 Simulated Birth Rectification	Full legal child after adoption	Yes	8–24 months	Very high	Families who used simulated birth
Rule 103 Change of Name	None	Almost never	1–2 years	Extremely low (<5%) data-preserve-html-node="true"	Almost never viable
Stepparent surname use	None	No	Immediate	N/A	Only for school/social use

Practical Recommendation (2025)

The overwhelming majority of family law practitioners and DSWD social workers now advise: File for domestic adoption under RA 8552 (or RA 11222 if simulated birth was used). The process has been drastically simplified since 2019, the three-year care period is almost always present in informal adoption cases, and the success rate is extremely high. Once the adoption decree is final, the surname change is automatic and permanent.

Attempting to change only the surname without adoption will almost certainly fail and waste time and money.

Families who have been raising a child informally for years should consult a licensed social worker or a family law lawyer specializing in adoption to begin the process. The child’s best interests — having legal parents, inheritance rights, and a birth certificate that matches reality — are best served by formalizing the parent–child relationship through adoption.