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Free or Low-end ZIP Code Databases

ZIP Code Database Alternatives (free & low-cost)

Our sources and verification processes deliver products based on very high standards. We believe most businesses will yield a greater return on investment by choosing a superior product. However, we also understand not every purpose requires this level of quality. Therefore we’d like to suggest alternatives for cases such as these.

Navigating the low-end Market

You can buy repackaged USPS ZIP Code data from several sources for under $50; however, for this level we feel you may as well go with a decent free database. Since low-end sources tend to come-and-go in any industry, it’s good to have some familiarity. Here are traditionally free sources that GreatData.com considers reputable. Please note, we do not have a relationship with these organizations nor are we responsible their products or service in any way whatsoever.

semaphorecorp.com (ZIP Codes and several other services as well)
boutell.com (a free ZIP Code database resource)
census.gov/geo/www/tiger (free US Census Tiger Data - which is what many low-end 3rd party ZIP Code databases are based on - read this first)

Critical Considerations

As mentioned, some free or low-end ZIP Code data is derived from Census data.

  • Be aware that Census data does not have every ZIP Code (only for General Delivery). This misses a large percentage of the ZIPs.
  • Census data is only accurate to the decade.
  • The census bureau uses a ZCTA code (which is ZIP Code like, but not exact as illustrated below) – see www.census.gov/geo/ZCTA/zcta

zcta versus zip code


Watch our ZCTA vs. ZIP Code video: ZCTA or ZIP Code Video

Others use straight USPS data. It goes without saying, free or low-end data offerings usually can’t bear the overhead of extensive data cleansing (and USPS data is not clean). However, we're already assuming that is acceptable in your case, so lets focus on other things to be on the look-out for.

  • Be particularly wary of using old data. ZIP Codes change a great deal every month.
  • If a ZIP Code boundary covers more than one city, determine if you need each city listed (~57,000 separate records) -OR- if you only need the primary city for each ZIP Code (normally around 43,000+ records). Most locators and address validation utilities need the former (57k recs).
  • Most low-end latitude and longitude centroids are based on geometric calculations - meaning they could fall in the middle of forestry land, large lakes, parks (e.g. Central Park) where no people live for miles. According to your needs, that may be fine for you. If you need population based centers, you will probably need commercial data (see our ZIP Codes with Lat/Lon; click the ‘more details’ tab at the top for an explanation of this topic).

Informative Resources

stackoverflow.com (read entire thread)
usps.gov
census.gov
zipcodereview.com
wikipedia.org/Postal_codes

Complements of GreatData.com...

Free ZIP Code Database (our own low-end, free ZIP Code database)