In order to improve mail processing efficiency, (Taiwan) Chunghwa Post will implement a new 3+3 postal code system (i.e. 6-digit postal code) starting from March 2020. The first three digits of "Administrative District Code" remain unchanged. The last 3 digits "delivery section code" are increased from the original 2 digits to 3 digits. Plan delivery sections in more detail, simplify processing operations, improve mail sorting efficiency, and improve delivery accuracy. Therefore, in the future,