ZIP Code Database with Lat/Long - Free File
Starting July 2015, the free ZIP Code database is no longer available. For those looking for a similar product (lower-end than GreatData's commercial products, but reputable*), you might like this one at softwaretools.com. ($29.99 commercial license, updated regularly)
* How the softwaretools.com
file differs from GreatData’s Enterprise ZIP Code Database: The softwaretools database provides unrefined postal data to those who’s needs allow the level of quality inherent in USPS data with little to no processing. It’s similar to many low-priced products on the market. Conversely, Greatdata’s enterprise grade database
uses multiple sources and algorithms that have matured for 20 years making it a truly Enterprise Class data that is highly accurate. Our verification and standardization process ensures that it is extremely clean, rigidly standard/ uniform, and has no duplicates. It contains precise population-based latitude/ longitude centroids, Area Codes, Time Zones, FIPS, MSA Codes, and much more.