5-2.4 PS Form 3877, Firm Mailing Book for Accountable Mail

You need to submit PS Form 3877, Firm Mailing Book for Accountable Mail, only when using approved extra services listed in DMM 503.1.0 (“Extra Services for Express Mail”). Postal Service acceptance personnel sign and date the PS Form 3877, which serves as a record of the pieces shipped. PS Form 3877 is available at http://about.usps.com/forms/ps3877.pdf.