When is the right time to use Certified Mail? Upgrade to Stamps.com Premier Purchase Certified Mail Forms USPS Information Track your Certified Mail Certified Mail is an affordable, efficient way to get tracking information and signature confirmation on mail sent using a variety of USPS mail classes. Certified Mail gives you peace-of-mind for important documents and packages and meets legal requirements as proof of mailing and delivery. Here are a few more things you should know about Certified Mail: You can use Certified Mail in conjunction with Priority Mail or First Class Mail only. The USPS maintains a record of delivery for all Certified Mail at the local Post Office where your mailpiece was delivered. To receive this proof of delivery, you may purchase Return Receipt when you send the original Certified Mail ($1.75) or at any time after the mailpiece has been delivered ($3.25). A new electronic Return Receipt is currently being tested by the USPS. For an additional fee you can specify that only a particular individual signs for a piece of mail. This extra security feature provides peace of mind when sending highly sensitive documents or packages.