Tags: postal codes, database address fields, Univeral Postal Union (UPU)
Afghanistan now has a 4-digit postal code, placed below the city or province name. Countries continue to establish postal codes (ZIP code, PIN code, PLZ, etc.) with the encouragement of the Universal Postal Union (UPU). Postal codes confer all kinds of benefits: allowing for better automated mail sorting, helping with sorting mail addressed in different scripts or languages, identifying a geolocation, and more.
Whether those postal codes are used is a completely different issue. From Afghanistan and Albania alphabetically to Vietnam and Zambia, the postal codes are not frequently used in 55 of the 170 countries with codes. Indeed, the code use can best be described as occasional to rare in those 55 countries.
When designing response forms or designing a database, a required postal code field for all countries that official have one is going to create problems. That field will not be completed on forms, leading to abandoned inquiries or orders. In a database, it will not contain a valid value in some or most cases, resulting in poor data quality. Nobody wants to encourage either of these problems.
Yet you do want to have a postal code if possible and certainly want them in countries where they are used. Here are a couple suggestions to find out if postal codes are used or not.
1. Buy the completely revised 2012 edition of the Guide to Worldwide Postal Code and Address Formats. We are now accepting pre-publication orders that will be shipped in February. The online version is continually updated and we’re adding information on whether the codes are used or not as we update to the 2012 edition.
2. Check the designated postal operator’s postal address on their web site if they provide one. If there is no postal code, then it is not used consistently in practice.
3. Check the addresses of embassies in that country’s capital. Larger countries list their embassies online and provide local addresses for them in most cases.
As always, I can be reached by email if you have questions or want more information.