Taiwan is also a member of the WTO and its import of goods is subject to WTO rules. The mainland and Taiwan have not realized the three links so far, and many goods from Taiwan are re-exported into the mainland. Therefore, all the commitments of China's accession to the WTO are applicable to Taiwan. Because the nature of the WTO is different from that of the United Nations, accession to it is not subject to the strict limitations of sovereign states. Therefore, some non-sovereign countries also join in the name of regions or special customs zones. This is the case with Hong Kong and Taiwan. The WTO's MFN clause applies to Taiwan.
So, the duty rate is calculated according to the most-favored-nation rate.