Kōshi has a well-developed transport infrastructure, featuring Kumamoto Airport located about 20 km away, which offers international flights. The railway network is served by the JR Kyushu line, connecting major cities. Major courier services such as Yamato Transport and Sagawa Express operate here, providing reliable delivery options. Typical delivery times from abroad range from 3 to 7 days, depending on the shipping method chosen. Notable customs features include the requirement for invoices on goods and adherence to safety standards.