Postal codes (Chinese: 郵遞區號; pinyin: Yóudì qūhào; Pe̍h-ōe-jī: Iû-tē khu-hō) in Taiwan is a system of three + three digits used by Chunghwa Post.[1] There are 368 sets of three-digit codes for townships, county-administered cities, and districts in Taiwan.
The cities of Chiayi and Hsinchu have a single code covering all their districts. The uninhabited islands Pratas (Dongsha) and Spratly (Nansha) each have a single code. The uninhabited Senkaku Islands (Diaoyutai) (administered by Japan) have a code, but there are no deliveries.
Omitting the supplementary three digits is ordinarily acceptable, especially for general public, while using a six-digit code is expected for corporate customers who send large-volume mails, which will speed the delivery of the mail.[2]