National Internal Revenue Code (NIRC)
Section 182. Stamp Tax on Foreign Bills of Exchange and Letters of Credit. - On all foreign bills of exchange and letters of credit (including orders, by telegraph or otherwise, for the payment of money issued by express or steamship companies or by any person or persons) drawn in but payable out of the Philippines in a set of three (3) or more according to the custom of merchants and bankers, there shall be collected a documentary stamp tax of Thirty centavos (P0.30) on each Two hundred pesos (P200), or fractional part thereof, of the face value of any such bill of exchange or letter of credit, or the Philippine equivalent of such face value, if expressed in foreign currency.