ZIP+4 Codes - GeoTAX_Premium - 7 - 7.7

GeoTAX Premium for Windows, UNIX/Linux, and z/OS

Product type
Software
Portfolio
Verify
Product family
Geo Addressing
Product
GeoTAX Premium
Version
7.7
Language
English
Product name
GeoTAX Premium
Title
GeoTAX Premium for Windows, UNIX/Linux, and z/OS
Copyright
2023
First publish date
1998
ft:lastEdition
2023-10-19
ft:lastPublication
2023-10-19T16:49:54.924301

The ZIP+4 Code is a recent innovation (introduced in late 1983) designed to direct mail to a more specific locality than the 5-digit ZIP Code provides. Essentially, the ZIP+4 Code is a subdivision of the ZIP Code geographic area.

In metropolitan areas, a ZIP+4 Code is normally assigned to each side of a street, between intersections — this is also called the block front.  In addition, ZIP+4 Codes are often assigned to a single PO Box or a group of PO Boxes, to a single building, to a single apartment or a range of apartments, or to a single firm, when the volume of mail warrants such an assignment. Every mailable address in the country is assigned to at least one ZIP+4 Code. And sometimes there is both a block-face and a building code, with or without a firm code, all available to an address. In this case, all are correct, but one is finer (smaller and more specific) than the others.

In non-metropolitan areas, boundaries for ZIP+4 Codes are not always so clearly defined. Nevertheless, they still are smaller subdivisions of a 5-digit postal zone and represent a great deal of geographic specificity useful for cross-referencing census geography.