1. A person legally born to a Thai father or Thai mother, whether born in or outside Thailand, are automatically granted Thai citizenship by birth. 
2. The applicant's name on the Thai Birth Certificate must match (i.e. written in Thai as it is pronounced in English) the name on the U.S. Birth Certificate
3. The last name of the applicant for a Thai Birth Certificate must be either the last name of a father or mother, and the spelling must adhere to the Thai documents of the father/mother.  

1. Before handing in the U.S. Birth Certificate to The Royal Thai Embassy, it must be authenticated by the Secretary of State of the issuing state. Click here to find more information

2. After having the U.S. Birth Certificate certified by the Secretary of State or state Authentication of the issuing state, the applicant must register, complete an application, and upload supporting documents for a Thai Birth Certificate online. This will allow an officer to verify the completness of the documents. 

Note: The applicant must register an application online and receive an approval by the officer before submitting the required documents to the Embassy by mail. Click here to fill out the application online 

3. After the officer has verified the documents and approved for accuracy, please send the documents to the consular section by mail using the address below:

Royal Thai Embassy (Consular Section) Attn. Registration 

2300 Kalorama Rd., N.W.

Washington D.C. 20008

1. An original and a copy of the authenticated U.S. birth certificate from Secretary of State

2. Two 2x2 inch color photographs of the applicant

3. An original and a copy of certificate from the hospital and a birth weight confirmation letter. This is specifically needed if the U.S. birth certificate does not specify the name of the hospital and/or birth weight.

4. Valid U.S. local ID cards of the parents, such as a Driver's License or State ID

5. Valid Thai ID cards of the parents 

6. Valid Thai passports of the parents

7. A marriage certificate

8. The following forms:

• Thai Birth Certificate application (which can be downloaded from the email used for registration) 
• A legal petition form for applying for a Thai Birth Certificate Download
• Mother's Testimonial Record (in case the father is a foreign national) Download
• Mother's Testimonial Record (in case the father and mother are not registered as married) Download

Note:

• If you do not wish to send the original documents such as the Thai passport, U.S. driver's license, and actual marriage certificate, you can use certified copies of these documents by a Notary Public instead.
• The person reporting the birth must come to the consular office to sign and pick up the documents in person by bringing a valid passport or Thai ID card that on the day of the appointment.
• If you wish to apply for a Thai passport, you can schedule an appointment with the officers to sign and receive your Thai Birth Certificate on the same day as your passport appointment. This option is available only if you intend to apply for a Thai passport within 30 days from the date of receiving your Thai Birth Certificate.

1. An original and a copy of the authenticated U.S. birth certificate from Secretary of State

2. Two 2x2 inch color photographs of the applicant

3. An original and a copy of certificate from the hospital and a birth weight certificate This is specifically needed if the U.S. birth certificate does not specify the name of the hospital and/or birth weight.

4. Valid U.S. local ID cards of the parents, such as a Driver's License or State ID

5. Valid Thai ID cards of the parents

6. Valid Thai passports of the parents

7. A marriage certificate

8. The following forms:

• Thai Birth Certificate application (which can be downloaded from the email used for registration) 
• A legal petition form for applying for a Thai Birth Certificate Download
• Mother's Testimonial Record (in case the father is a foreign national) Download
• Mother's Testimonial Record (in case the father and mother are not registered as married) Download
• Notary Public for Signature Download

9. Two Postal envelopes for sending the Thai Birth Certificate back via USPS Priority Mail, with stamps priced at USD 10.45 each. Please clearly write your name, address, and phone number on the front of the envelope addressed to yourself. To ensure against loss, your postage envelopes must have a Tracking Number.

Note:

• If you do not wish to send the original documents such as the Thai passport, U.S. driver's license, and actual marriage certificate, you can use certified copies of these documents by a Notary Public instead.
• The officer will send supporting documents and the actual Thai Birth Certificate to the notifier for signature in the 'Notifying person' section. After the notifier has signed, please proceed promptly to deliver the aforementioned Thai Birth Certificate to the officer for verification and storage in the system for the next steps
• If the notifier is unable to return the signed Thai Birth Certificate to the officer, the Thai Birth Certificate application will be considered incomplete.