Frank'S Compulsive Guide to Postal Addresses Postal Codes Postal codes, in countries that have them, are usually numeric, sometimes containing a space or a hyphen. Different countries use different terms for postal codes (e.g. Zone Improvement Plan, Postleitzahl) and different abbreviations for the terms (e.g. ZIP, PLZ, CEP, CAP, PIN). See the Wikepedia page on Postal codes.