Yes. This is a common question ask daily. You can send USPS Certified Mail to a P.O. Box in the United States. USPS Certified Mail letters are addressed and delivered to the PO Box with no changes in mailers process.   In other words you just address the letter using the PO Box instead of the street delivery address.
 
When the letter carrier delivers the letter the process that documents the letter was recieved  at the delivery address is a little bit different.  A delivery notification card is placed inside the PO Box instructing the recipient they have a Certified Mail waiting for pick up from the Post Office window clerk.  Because USPS requires someone to sign for each Certified Mail letter when each letter is delivered the delivery notification card must be presented to the window clerk at the USPS Post Office. Then the  recipient signs the delivery confirmation and the Signature, date and time of the delivery confirmation are electronically captured and recorded by USPS. This is how the United States Postal Service handles the delivery when you send a USPS Certified Mail letter to a PO Box.

You can save time and money by sending USPS Certified Mail using Electronic Return Receipts available as apart of each Certified Mail Envelope. These envelopes have been approved by USPS and do not use any forms or stickers. This makes sending USPS Certified Mail with the Electronic Return Receipt fast and easy.  The Certified Mail Envelopes provide proof of mailing, in-route delivery tracking  and final proof of delivery from USPS even if you are sending the letter to a P.O. Box. This replaces the old fashioned Green Card that would get lost and is hard to manage for mailers. You can address your letter then print Certified Mail tracking and article numbers, bar codes and more online.  No software to buy, or forms to fill out. Log-on to www.Certified-Mail-Envelopes.com and begin to send your USPS Certified Mail fast and easy.

To learn more about automating USPS Certified Mail through our enterprise solutions call us 800-406-1792.