Regulations

1. Last names must not resemble, or be intended to resemble, the names of the King or Queen.
2. Last names must not resemble, or be intended to resemble, the name of royal titles, unless conferred by the King on the person's parents or children
3. Last names must not be the same as last names conferred by the king or other Last names previously registered.
4. Must not contain any vulgar language nor meaning.
5. Must not be more than 10 syllables, unless it is royal title.
6. Must have a meaning in Thai language according to the Thai dictionary, with correct spelling.
7. Last names not conferred by the King will not be permitted to use "Na" in front of the Last name.
8. Last names must not resemble the name of Bangkok or any of His Majesty the King's residences.

Required Documents

1. House Registration Certificate.
2. Identification Card.
3. Alien Registration Card (applicable to aliens).

Procedures

1. File a request with the local Registrar where the House Registration Certificate is registered.
2. The Local Registrar will review the documents for accuracy before forwarding them to the Registrar at Central Registration Office.
3. Once the request proceeds and is approved by the Registrar at the Central Registration Office, the local Registrar will issue a Change of Last Name Certificate to the applicant as evidence. A service fee of 50 baht is required.