The Inland Revenue Department doesn't care whether you write off foreign exchange income. If you export them, he will return them to you. The tax bureau and the administration of foreign exchange belong to two different departments.

However, it should be noted that if the payment is not received within 180 days from the date of export, it is necessary to apply to the foreign exchange bureau for an extension of write-off. Moreover, the safe allows the difference to be written off, and the difference between the amount written off and your foreign exchange income can be written off within 5%.