PostalCodeData.com is a company of GreatData and a reseller of US, Canadian, and Mexican postal databases. Unlike GreatData's core products, this data is relatively untouched by our processes. We add only minimal refinements (usually case consistencies and such) plus latitude and longitude fields. In a nutshell, you get the same data you can buy from the postal system; but geocoded and at a fraction of the price. Like most companies who resell licensed postal data, we are able to do so at a lower price while being profitable by selling large quantities.
What can you expect regarding quality? We believe the quality of this product is similar to most comparably priced products on the market. It's always up-to-date and will only contain the imperfections that are already inherent in the data sold by the postal service (US Postal Service, Canada Post, and Mexican Postal Service). If this meets your specific need, we hope you’ll give us a try. If your need calls for enterprise-class data that is extremely accurate, highly refined, and cross-verified from multiple authoritative sources, may we humbly request that you consider the enterprise-class products at GreatData.com