Postal/Zip code data files are always tough to track down. The GISDataDepot gets numerous requests from people looking for resources and pointers to help them find free postal code GIS datasets. Unfortunately, free postal data in a useable format is very tough to come by. We've put together this collection of resources to help you out. Commercial data is available, however, don't expect to get it for free - lots of work has gone into developing this data and keeping it up to date. Unfortunately, many people have now come to expect data to be easy to find and available for free. This is not the case with quality postal/Zip code data, particularly since the data requires constant updates. Note, this page is continually updated so please check back or feel free to contribute a resource.

ZIP Code Resources

Election Data Services
Election Data Services Inc. is a political consulting firm specializing in redistricting, election administration, and the analysis and presentation of census and political data with GIS.ZIP+DISTRICT is a database that links 5- and 9-digit ZIP Codes with congressional and state legislative districts (Senate and House) in all 50 states. The ZIP+DISTRICT database is updated with quarterly releases of new postal data and district boundary changes.

Imagem Sensoriamento Remoto
Brazilian street centerlines with ZIPs for many Brazilian cities. Contact fmortara@img.com.br

US Census Bureau
This Equivalency file contains the 300 characters in the identification section of the data dictionary used in all 1990 STF's. It equates 1990 census block numbers with the areas that approximate October 1991 ZIP Codes used by the USPS to deliver mail. The File provides a 5-digit ZIP Code for each land block number within each State with a few exceptions

The 1990 Zip Code by State file is comma separated values, ASCII text, one record per line. The field/record layout is as follows: Click Here to Download 670 kb

Field 1 - State Fips Code
Field 2 - 5-digit Zipcode
Field 3 - State Abbreviation
Field 4 - Zipcode Name
Field 5 - Longitude in Decimal Degrees (West is assumed, no minus sign)
Field 6 - Latitude in Decimal Degrees (North is assumed, no plus sign)
Field 7 - 1990 Population (100%)
Field 8 - Allocation Factor (decimal portion of state within zipcode)

The TIGER 98 CD file, distributed by the Census Bureau and available (usually for free, or nominal duplication charge) throughout the United States from Affiliated State Data Centers, contain zip+4 points in zip-compressed file format. By extracting these files and importing them into any GIS package which can read TIGER file format, a user can develop "relatively" accurate zip+4 geo-coding capability at virtually no cost (other than staff & cpu time to build the data set). Kevin F. Byrnes, demographer with Virginia Dept. for the Aging did this for the Commonwealth of Virginia in less than 4 hours using PK-Zip and Caliper's Maptitude 4.1 on his home PC and now has a data layer for Virginia containing over 450,000 zip+4 data points. Thanks for the tip Kevin!

National Address Server
Given a valid U.S. postal address, this server attempts to rewrite the address in the proper format along with the ZIP+4 code. If it is successful, you can retrieve a Postscript or a GIF file of the address for printing, with a barcode!

Map Analysts's European ZIP Code Map
Seamless European zip-code map for 35 countries. Netherlands, Belgium, Luxembourg, France, Spain, Portugal, Italy, Swiss, Austria, Germany, Denmark, UK, Ireland (Wards), Norway, Sweden, Finland, Poland, Czech Republic, Slovakia, Hungary, Romenia, Greece, Latvia, Lithuania, Estonia, Turkey, Bosnia, Slovenia, Croatia, Former Yugoslavia, Macedonia (incl. Andorra, Monaco, Liechtenstein and Vatican City) (Bulgaria one position) - Commercial Data Product

Japanese Zip Codes
Japanese zip code info is available here (in Japanese). If help or additional details are required you can contact Reese W. Plews at plews consulting, Tokyo, rplews@tkb.att.ne.jp

UK - AFD Postcode Address Management Solutions
Graticule sells desktop and Internet products from AFD Software Ltd for name and address management. The products offer easy, accurate and cost-effective access to the Royal Mails Postcode Address File. AFD software helps you handle names, addresses and mailing lists on your computer. Products include Postcode & ZipAddress, Postcode Plotter, Postcode Plus, Names & Numbers

Geoplan
In association with Royal Mail in the UK, are the leading producers of UK Postal boundaries for any desktop mapping system/ GIS. The available products range from: 1.6 million unit Postcode boundaries, 9,000 Postcode Sector boundaries, 2,700 Postcode District boundaries, and 124 Postcode Area boundaries. All products are supplied with their associated centroids together with residential, non-residential and large user delivery point counts and provide complete and seamless coverage of the UK. The Postcode boundaries are maintained from Royal Mail information and updated files are released every six months. All data is available in a wide range of formats including ArcView, ArcInfo, MapInfo, Tactician, DXF, Atlas BNA and many others. In addition, Geoplan offer associated census, business and media information for strategic business planning applications.

Sammamish Data Systems
Providers of Postal Carrier Route files that are updated quarterly within a month of the release of the Postal Service's ZIP+4 database. Boundaries literally go down back fence lines as they do in the real world. The timely, quarterly updates allows mailers to use these files to incorporate their CASS certified lists with the latest carrier route configurations. The only supplier of ZIP+2 boundary files in the United States. They also have ZIP+4 Centroid files which are also updated quarterly and incorporate information from several sources to insure the highest level of precision. Data are available in GeoSight's .RFX format, MapInfo's .MID/.MIF format and an ASCII string format. Printed maps are also available for individual areas.

Mediapost
In France MEDIAPOST, (www.mediapost.fr) subsidiary of the french Post Office, sells Franch Zip codes (around 500 Euros)

ZCTAs
The Census Bureau has developed a product known as ZCTAs. ZCTAs are not U.S. Postal Service ZIP Codes. ZCTAs are approximate area representations of United States Postal Service (USPS) ZIP Code service areas. The U.S. Census Bureau has created ZCTAs to meet requests by data users for statistical data by ZIP Code area. The term ZCTA was originated to differentiate between true USPS ZIP Codes and these approximations. More info is available from the Census Bureau website. Look for this product to be available as a free download in the future! (we hope)

ZIPList5 Geocode from Zipinfo.com
ZIPList5 Geocode is a ZIP code database (Canada or USA) containing the latitude, longitude, city name, state abbreviation, county name and county FIPS code, primary telephone area code, ZIP code type, time zone, and daylight savings time flag for each of the nearly 43,000 5-digit ZIP codes defined by the US Postal Service. Updated monthly. They also have a free mechanism on the website where you can enter a zipcode and you are returned the lat/long, time zone, county name, area code, or congressional district... pretty cool!

ZIPTracker
Zip Tracker is a Shareware product that enables you to get a listing of all the ZIP+5 codes for a city or State in question. A 1MB free download iss available from the website.

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