Do you mean that international transportation companies can't declare at other ports after tax registration at several domestic ports? Yes According to the regulation of "Non-resident Enterprises Engaged in International Transport Business at Multiple Ports in China", if they want to carry out international transport business at multiple ports in China, they only need to choose a place where the business takes place and go through tax registration. If the business takes place at other ports, you only need to register with the competent tax authorities where the business takes place.