Are the witnesses and or executor/administrator supposed to be of Thai or foreign nationality?

Witnesses and or executor/administrator of a last will in Thailand can be Thai and/or foreigner.

Witness:

The following person cannot be witness of the last will:

1. Person not yet of legal age (i.e. section 19 civil code: a person, on completion of twenty years of age ceases to be a minor and becomes sui juris (meaning possessing full social and civil rights; not under any legal disability, or the power of another, or guardianship) or section 20: a minor becomes sui juris upon marriage, provided that the marriage is made in accordance with the provisions of section 1448)
2. Person of unsound mind or quasi-incompetent person under Court’s order
3. Deaf or dumb or blind person
4. The Legatee of or under the last will and his or her spouse.

Executor:

The following person cannot be executor :

1. Person not yet been on completion of legal age (see above under 1)
2. Person of unsound mind or quasi-incompetent person under Court’s order
3. Bankrupt Person under Court’s judgment

Under Thai law there is no registration system for the last will but the last will can be made by the testator (generally only applies to Thai nationals):

1. in the form of giving statement to the authority about your last or final wishes and then the competent authority will prepare the last will for you (using their own Thai script format), or
2. you prepare and execute the last will yourself and seal it and then bring it to the competent authority for their retaining (the secret last will).

Option 1: Official Last Will.

1. The testator has to bring 2 witnesses to district office and give statement to the official before the 2 witnesses to write the last will for him.
2. The official will then record the statement and read and speak out the content to the testator and the witnesses.
3. Following the statement given the testator and witnesses sign in the last will.
4. The district official will date and endorse the last will and affix government seal.

Option 2: Secret Will.

1. The testator has to execute the last will (sign last will without witness), seal it (envelop) and then sign across it.
2. The testator has to bring 2 witnesses and the signed last will inside the envelope to district office and give statement to the before the witnesses that the paper inside the envelope is his/her last will. The testator also has to notify the name and address (domicile) of the person who write or prepare the last will.
3. The district official will make a record of above statement and dated on the envelope on which the last will being covered, the official will endorse and affix the government seal on the envelope and the 2 witnesses will also sign there.