A Thai having alien spouse who has a foreign spouse (either by legal or illegal marriage) who would like to purchase an alien spouse has to confirm in a certify letter that the spending on land is his/her separate property or personal asset. The proceeding of certify letters are as follows:​

1. In case an alien spouse lives in Thailand:

1.1 In case an alien is a legally spouse, a Thai and an alien spouse have to give joint confirmation in certify letter according to the forms which were specified by the Department of Lands in front of the competent officer in the date of registration of rights and juristic act that thespending on land is sin suantua (personal property) of a Thai not sin somros (marital property between husband and wife) of the spouse.

1.2 In case an alien is an illegally spouse, a Thai and an alien spouse have to give joint confirmation in certify letter according to the forms which were specified by the Department of Lands in front of the competentofficer in the date of registration of rights and juristic act that the spending on land is personal asset of a Thai only not common property.

2. In case an alien spouse lives in Thailand but could not proceed according to No.1: In case an alien spouse lives in Thailand but in the date of registration an alien could not give written confirmation together with a Thai in front of the competent officer at the registration land office. A Thai and an alien spouse shall lodge the application of testimony form for confirming that the spending on land is sin suan tau or personal asset of only a Thai not sin somros orcommon property by lodging the application to the competent officer at provincial land office or any branch land office. After, a Thai who would like topurchase land shall bring original of certify letter to the competent officer for registration of rights and juristic act accordingly.

3. In case an alien spouse lives in oversea and could not lodge the application of testimony form according to No.1 and No.2. An alien has to contacts the embassy, consular or notary public for giving testimony of an alien spouse in certify letter according to the forms which were specified by the Department of Lands that the spending on land is sin suan tau or personal asset of a Thai not sin somros or common property one. The embassy, consular or notary public has to certify that person, who applies for certify letter, is truly spouse or they live together as husband and wife with a Thai. After, a Thai who would like to purchase land shall bring original of certify letter to the competent officer for registration of rights and juristic act accordingly.

4. In case a Thai who has legal or illegal alien spouse, if a Thai could show the evidence indicates that the spending on land is sin suan tau or personal asset according to section 1471 and section 1472 of The Civil and Commercial Code, the competent officer could registers rights and juristic act for a Thai without testimony form of Thai nationality and an alien spouse according No.1 – No.3.

5. In case a Thai, who has alien spouse, purchased land before 23 March B.E. 2542 but informed or submitted a false document declaring that he/she is single. For relaxation of rule to a Thai, who has legal or illegal alien spouse, purchased or owned land after the date of marriage. And a Thai informed or submitted a false document to the competent officer declaring that he/she is single or a Thai has no alien spouse prior to the date of issuing letter of Ministry of Interior, Urgent No. MOI 0710/Circulation 792 dated 23 March B.E. 2542. An alien spouse and a Thai shall together give a written confirmation in certify letter in front of the competent officer that the spending on land is sin suantau or personal asset of only a Thai not sin somros or common property one. After, the competent officer retains documents in dealing file. If an alien spouse who lives oversea and could not give written confirmation together in front of the competent officer, an alien has to contacts the embassy, consular or notary public for giving testimony of an alien spouse in certify letteraccording to the forms which were specified by the Department of Lands that the spending on land is sin suan tau or personal asset of a Thai not sin somros or common property one. The embassy, consular or notary public has to certify that person, who applies the certify letter, is truly spouse or they live together as husband and wife with a Thai. After, a Thai who would like to purchase land shall bring original of certify letter to the competent officer for retaining documents in dealing file.

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