ZIP Code Overlays: Boundaries, Polygons and Points

In GeoMetrx there are three ZIP Code Overlay options: Boundaries; Polygon; and Point.

– The Boundaries overlay provides exactly that, a visible boundary, or border, around a polygon shape representing a STANDARD ZIP Code area, which is assigned to a particular geographic area of homes and businesses.

– The Polygon Overlay adds the STANDARD ZIP Code Number to the map.

– The Point Overlay adds ZIP Code numbers to the map that are assigned to either P.O. Boxes or UNIQUE addresses. UNIQUE addresses are ZIP Codes that have been assigned to a single high-volume mail recipient such as a business, university or government entity.

In the above example 75208 is a Standard ZIP Code assigned to all the homes and businesses within the blue polygon boundary surrounding it, while 75285 and 75263 are assigned to a Unique entity and P.O. Box, respectively, and are represented as points.

When uploading data to GeoMetrx it’s important to understand the difference between the polygon ZIP Codes and point ZIP Codes. If your dataset includes any Unique or P.O. Box ZIP Codes, and you only select ZIP (Polygon) the software will treat those codes as invalid. However, if you choose the ZIP (Point/Poly) option when uploading all the ZIP Codes in your dataset will upload properly.

If you still bump up against and invalid ZIP Code when uploading data, it may truly be invalid. Our GeoMetrx ZIP Code database is updated regularly in conjunction with USPS changes. The USPS regularly realigns ZIP Codes in an effort to accommodate population growth and operational needs. The USPS maintains an up-to-date online look-up tool which is the best resource to check the validity of a ZIP Code. To access this resource visit:

If you click the “Cities by ZIP Code” tab, you can input individual ZIPs without also providing an address. The look-up results are displayed immediately in the dialog window as shown below:

For more information on how to obtain access to GeoMetrx datasets, contact us today at 1.888.848.4436.