Those who need to pay taxes and those who serve foreign trade must pay taxes. However, if the amount is less than the equivalent of $30,000, the bank will not review the tax certificate of external payment, and banks above 30,000 will require tax certificates. Non-trade payment of foreign exchange refers to the behavior of domestic enterprises to pay foreign exchange to overseas enterprises or institutions when they have labor income or obtain domestic profits, interests, rents, royalties and other income related to capital projects.