Provider: Sammamish Data Systems, Inc.

Spatial Insights is pleased to offer Sammamish Enhanced TIGER ZIP + 4 Centroids. Based on the new TIGER/Line 2002 files and updated quarterly, the ZIP + 4 centroid files combine the latest information from the new TIGER/Line 2002 files, the U.S. Postal Service’s latest AMS-II files, U.S. Geological Service survey data and our own proprietary data.

Several unique features are incorporated to produce more accurate ZIP+4 centroids. For example, they are distributed along street segments as the addresses change. In addition, most centroids are offset about 30 feet from the street segment on the proper side of the street. These offset centroids clearly separate the ZIP+4 centroids on facing blocks, thus contributing to more accurate and useful ZIP+4 centroid locations.

This extremely accurate and detailed file is ready for use with desktop mapping and GIS systems.

Please contact us for pricing information.

Learn More About Sammamish ZIP+4s


Since 1993, Spatial Insights has been leveraging unique partnerships with the industry’s leading providers of mapping software and data to provide solutions tailored specifically to meet our clients’ diverse needs.


For more information about our services, or how we could help your business, please contact us at 800.347.5291 or fill out the form below.