Why is the zips database missing zip codes?

Sometimes users will compare our zip code data to other sources and find that it doesn't contain every zip code in their other data source.  Almost always, this is because our database only includes valid and active zip codes.  You can go to the USPS website to see if an zip is valid:

https://tools.usps.com/zip-code-lookup.htm?citybyzipcode

If the zip code is not valid, you'll see an image like this:

If the zip code is valid and you believe that it is missing from our database, please contact us.