What are ZIP+4 Codes? - PostGrid

TABLE OF CONTENTS What are ZIP+4 Codes? Imagine you are living in Georgia and want to mail a letter or a postcard to your customer residing in Atlanta. So, Georgia is the first carrier to receive the mail item and does not need to know the exact a…

source https://www.postgrid.com/what-are-zip4-codes/

source https://byronnoell.blogspot.com/2022/06/what-are-zip4-codes-postgrid.html