The validity period for licences may be extended for goods that are manufactured to specifications or for items which require a longer delivery period. Payment for Imports Payments for imports are usually made by authorised banks upon submission of documents such as commercial invoice, bill of lading and import licence. To enable the importer to open an import letter of credit, the exporter must furnish a pro forma invoice. The tariff in Thailand is based on the Harmonised Commodity Description and Coding Systems. Duty rates apply on the same basis to all countries.
Most customs duties are ad valorem, though some are specific.
Import Duties on Computers Effective from July 1991, Thailand has reduced import duties on computers and computer parts. Preferential rates are granted to goods originating from any of these countries. Agricultural goods are excluded from the scheme. Methods of Payment Payments for imports are purchased by authorised banks upon submission of documents eg. Letters of credit are the most commonly used mode of payment.