An important consideration in any Thailand Real Estate Law and Planningtransaction is finance. A mortgage is a document that is normally used to support a loan agreement. The document allows the lender to foreclose on a property to be paid for a loan that a debtor has defaulted on. In Thailand, a mortgage agreement must be in Thai language, registered and meet other requirements of Thai law.

A land mortgage must be executed in writing, meet the requirements of Thai law as found in sections 702-746 of the Thailand Civil and Commercial Code
and be registered with a relevant office of the Land Department. However, a land mortgage does not necessarily cover the rights over buildings built on the land after the mortgage date, unless it has been explicitly stated in the mortgage agreement. Buildings and other immovable property may be mortgaged separately from the land.

The documents required at the Land Department vary based on whether the lender is a foreigner, a Thai national or company, or other juristic entity. There are several government forms which must be completed in addition to the private mortgage agreement.

A mortgage allows the lender to foreclose on land if a debt on the land is unpaid. The land will typically be sold by public auction. If the funds realized from a sale are not sufficient to pay the underlying loan, a deficiency judgment for the unpaid amount may be obtained.