Postal codes in China
Postal codes in the People's Republic of China (邮政编码) are postal codes used by China Post for the delivery of letters and goods within mainland China. China Post uses a six-digit all-numerical system with four tiers: the first tier, composed of the first two digits, show the province, province-equivalent municipality, or autonomous region; the second tier, composed of the third digit, shows the postal zone within the province, municipality or autonomous region; the fourth digit serves as the third tier, which shows the postal office within prefectures or prefecture-level cities; the last two digits are the fourth tier, which indicates the specific mailing area for delivery.