An Outward Code is the first part of the postcode(before space). It is 2-4 characters long and always start with a letter but may end up with a number or letter. It is used to indicate the local area where a mail needs to be delivered. In the postcode DH6 4SB , DH6 is the Outward Code. Postcode finder tool is designed to explain the Outward Code of the address you are searching. An Outward Code is further divided into Postcode Area and Postcode District.