If you choose the "standard return address" option, you’ll be able to add endorsements to your envelopes that tell the Post Office™ what to do with undeliverable mail. Your address will also be validated against our list of official delivery addresses.

If you choose custom text, you’ll be able to put anything you want in the upper left of your envelope - such as a company motto or description - along with the return address. But, you won’t be able to add endorsements.