How is it possible that for US income the lower tax treaty is applied?

The United States has introduced a system where, under certain conditions, the lower tax treaty rate can directly be applied at source. DEGIRO has entered into an agreement with the Internal Revenue Service (US tax authority) to make use of this system. This way DEGIRO enables its clients to benefit from the lower tax treaty rates provided for in the tax treaty between their country of tax residence and the United States. In general, the U.S. tax treatie provide for a reduced withholding tax rate of 15% on dividend income.