Certificate of Mailing — Firm - USPS
about.usps.com › forms › ps3665of the form, number them consecutively to show sheet number and total number of sheets (such as “Page 1 of 4,” “Page 2 of 4,” etc.). 11. Present PS Form 3665 and the mailing as follows: ¡ When the mailing has fewer than 50 mailpieces and less than 50 pounds, present the form and mailing at a retail Post Office™ location.