Addressing an envelope to a post office box address is just like addressing envelopes to any other type of address. Of course, before you can address the envelope, you need the name of the recipient, the post office box number and the city, state and Postcode. This information should be written neatly on the front of the envelope. And, when addressing any type of mail, be sure to follow the U.S. Postal Service guidelines.
Place the recipient's name on the first line. You should include the person's full name. The name should be near the centre of the envelope.
List a company name, if applicable, underneath the person's name.
Enter the post office box number next. Write it as "PO Box 1234," for example.
Enter the city, state and Postcode on the next line. Use the Postal Service's two-letter state abbreviations. Be sure to use the correct Postcode as well. Find Postcodes on the Postal Service's website.
Avoid using commas or periods when addressing mail, according to the Postal Service. Instead of writing, "P.O. Box," write "PO Box." Also, do not put a comma after the city.