United states postal code contains 5 digits to be used in postal services. A postal code is used by the United States Postal Service (USPS). It was first introduced in 1963, with the basic format consisting of five digits. With the help of zip code/postal code, one can send and receive parcels as it is mandatory for sending shipments from one place to another place. Zip codes play a vital role in shipments and also finding a zip code of a particular state, county or city can be a very hectic and time-consuming job that can take several hours. So here we worked very hard for you in order to provide you with all united states postal codes for each and every state, county and city in a very easy and sorted manner which makes it easier to find out particular USA zip codes without much effort.