How to Use a PS Form 3877 Firm Mailing Book

USPS Form PS 3877, the Firm Mailing Book for Accountable Mail, is a document used to obtain proof of mailing for multiple items at once. It is designed for situations where a business or individual is sending three or more pieces of mail that require an extra service, such as Certified Mail, Insured Mail, Signature Confirmation, or Registered Mail. Instead of getting a separate receipt for each item, this form consolidates the information, creating a single, official record of acceptance by the United States Postal Service (USPS) for your records.

Preparing Your Firm Mailing Book

You must obtain the current version of PS Form 3877. The official form is available on the USPS website for download. While the official form is recommended, privately printed or computer-generated versions that are nearly identical to the official PS Form 3877 may be used. However, these custom forms must be approved in writing by the local postmaster or the manager of Business Mail Entry where the mail will be presented. Before filling out the form, gather all mailpieces and their corresponding documentation.

The form must be completed in ink. At the top, you will enter your name and full return address. For each entry, you must record the full name and address of the recipient exactly as it appears on the mailpiece.

Next to the recipient’s information, you will find columns for postage and fees. You must enter the applicable postage amount for the weight and service level of the item. You will also record the fees for any extra services used, such as Certified Mail, Return Receipt, or Insured Mail. The article number, a unique number found on forms like the Certified Mail PS Form 3800, must be transcribed into the designated column on the PS Form 3877. This number links the entry on the firm mailing book directly to the physical mailpiece.

If you are sending items that are not in the same order as they are listed on the form, you must number each line on the sheet and lightly write the corresponding number on the mailpiece itself. After listing all the articles, you will total the number of pieces and enter it in the space provided at the bottom of the form. For certain services, such as Collect on Delivery (COD), Priority Mail Express, and Registered Mail, a duplicate copy of the form is required.

Submitting Your Mail at the Post Office

You must bring both the completed form and the corresponding articles to a retail associate. The mailpieces should be organized in the order they appear on the form unless you have numbered them. This preparation facilitates a smoother and faster transaction at the counter.

The postal clerk will perform a verification process. They will compare the details on each mailpiece against the entries on your PS Form 3877. The clerk checks the recipient’s address, the article number, and the services and fees listed to ensure everything matches.

Once the clerk confirms the accuracy of your form and mail, they will accept the mail. The clerk will then use a round-dated stamp to postmark your PS Form 3877. This stamp imprints the date and post office location, validating the document. The stamped form is then returned to you and serves as your legal proof of mailing. The USPS does not keep a copy, so it is your responsibility to retain this receipt for your records.