You’ll need to prepare the ff:
1. Affidavit of Admission of Paternity or the Affidavit of Acknowledgment/Recognition, executed by the father, admitting and acknowledging paternity over the child.
2. Affidavit to Use the Surname of the Father (AUSF) - an affidavit to be executed by the father of the child, acknowledging paternity and allowing the child to use his surname
3. Certified True Copy of the Certificate of Live Birth of the child
4. Valid identification for both parents
Where to File:
The AUSF, together with the other documents, shall be filed at the Local Civil Registry Office (LCRO) where the child was born, if the birth occurred within the Philippines. If the child was born outside the Philippines, the AUSF shall be filed at the Local Civil Registry Office (LCRO) of Manila.
When to File:
The AUSF shall be registered within twenty (20) days from the date of its execution, otherwise the procedures of late registration shall be applied.
The LCRO will register the documents (the AUSF and the Affidavit of Admission of Paternity), and annotate them on the Certificate of Live Birth. Afterwards, the Birth Certificate will now bear the annotation: “ "The surname of the child is hereby changed from (original surname) to (new surname), pursuant to RA 9255."
P1,000-1,500 ang fees at the LCRO.