Registering legitimation of a child (Kor Ror 11)
How a father registers legitimation of a child at the district office, including the consent of the child and the mother required by section 1548 of the Civil and Commercial Code.
A child born to a woman who is not married to the father is by law the legitimate child of the mother (Civil and Commercial Code section 1546). The father becomes the legal father only through one of the routes in section 1547: a later marriage between the parents, registration of legitimation, or a court judgment declaring the child to be his.
Registration at the district office uses form Kor Ror 11. Section 1548 requires the consent of both the child and the mother. If either cannot or does not appear to consent, the registrar cannot proceed and the father must apply to the Juvenile and Family Court for a judgment in place of that consent.
Once registered, the child is the father's legitimate child, may take his family name, inherits as a statutory heir and is entitled to maintenance. Foreign authorities frequently ask for this record when assessing dependant visas or benefits for the child.
For use abroad, obtain a certified copy of the legitimation record from the registrar, have it translated into the destination language and run it through the Department of Consular Affairs and the destination country's embassy in the order that the receiving authority requires.
Documents to prepare
- National ID card or passport of the father, the mother and the child where applicable
- The child's birth certificate
- House registration of the father, the mother and the child
- Evidence of any change of name or family name
- Witnesses as required by the registrar
- Certified translations of foreign documents where a parent is a foreign national
Certification order
- Check the child's civil-registration status and whether the father is named on the birth certificate
- Arrange for the father, the mother and the child to attend the district office together
- File the legitimation application and give statements to the registrar
- Collect the legitimation record (Kor Ror 11) and certified copies
- Translate and certify the translation if the record will be used abroad
- Legalise at the Department of Consular Affairs and the destination embassy in the required order
Pre-filing checklist
- Confirm the child and the mother can genuinely attend and consent; otherwise prepare a court application
- Check that name spellings match across the birth certificate, house registration and passports
- Ask the district office in advance about witnesses and any local document requirements
- For overseas use, ask the receiving authority which language and which legalisation order it needs
Frequently asked questions
Can the father register legitimation on his own?
No. Section 1548 of the Civil and Commercial Code requires the consent of both the child and the mother. Without that consent the father must obtain a court judgment instead.
The father is already named on the birth certificate — is he the legal father?
Not yet. Being named is a civil-registration entry. Legal paternity arises only under section 1547: a later marriage to the mother, registered legitimation, or a court judgment.
The child is too young to give consent. What then?
Where the child cannot meaningfully consent, the registrar cannot complete the registration under section 1548, so the father applies to the Juvenile and Family Court for a judgment declaring the child to be his.
Can the child take the father's family name straight away?
Once the child is legitimate, the family-name change is possible under the Department of Provincial Administration's registration rules, but it is a separate application at the district office — it is not automatic.
What extra documents does a foreign father need?
Usually a passport, evidence of marital status and any foreign documents translated into Thai with the certification the registrar requires. Requirements vary by district, so ask before attending.
Can the legitimation record support a foreign visa application?
Yes, where the destination embassy accepts it. Normally you obtain a certified copy from the registrar, translate it, have the Department of Consular Affairs legalise it and then follow the embassy's own requirements.
How does legitimation affect inheritance?
A legitimated child is a descendant heir under Book VI of the Civil and Commercial Code and inherits from the father in the share the law provides.
The mother refuses to consent because of a dispute. What are the options?
The matter goes to the Juvenile and Family Court, which decides on the evidence — including scientific testing if a party asks for it — whether the child is the applicant's child.
For a document review before filing with a registrar or court, contact LINE @nycli, phone +66-83-249-4999 or email nycli@ilc.ltd. Our team will confirm the steps, anything still missing and a realistic timeline.