Proof of Mailing

Understanding the confusion surrounding what is considered ‘Proof of Mailing’, according to the USPS

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Understanding ‘Proof of Mailing’
There are various times when individuals and organizations must be able to provide or retain proof that a mailpiece was submitted to the USPS for mailing or a mailpiece has been received by the recipient. Oftentimes, this need is driven by state or local requirements, resulting in fines if published guidelines are not met. Others may just want the peace of mind knowing an important document or package has been delivered.
Proof of Mailing is not listed as product or service within the USPS, yet the USPS offers various products to provide information necessary that provides proof that will meet individual’s needs.
Products that can meet expectations for proof of mailing are varied in service and costs. When there are written requirements, it is important to know if a specific service is required to meet proof of mailing. Often, requirements are not specific, and it is left to the mailer to determine what to provide to meet requirements. Communicating with the entity requiring proof of mailing is probably the best way to prevent unwanted fines.
Proof of Mailing and Delivery sources are the USPS Retail Receipt, the Certificate of Mailing, whether single or bulk mailings.
USPS Retail Receipt
When presenting a package for mailing at a USPS retail facility, you receive a receipt that can be retained as proof of mailing and lists a tracking number. With this, you will notice that the receipt does not list the recipient address.
Certificate of Mailing

A true method for providing proof of mailing through the USPS is accomplished by using Certificate of Mailing. Certificate of Mailing is a process to provide mailing to the USPS and have a receipt showing the pieces were received by the USPS for mailing. To utilize this service, you must complete the USPS form 3817, listing the recipient and address for your 1-3 mail pieces. Each mailpiece must have the required First-Class postage affixed to it. You will pay the fee for the service and affix the postage for the service to form 3817.

As of January 9, 2022, the fee for Certificate of mailing from form 3817 is $1.65.

For mailings of more than three pieces you will need to complete USPS form 3665, listing all mail pieces in the mailing. You can use as many copies of the form, to include all the pieces in your mailing. Within the Form 3665 you can include a specific identifier for each mail piece for your purpose, such as an Account Number, registration number, etc.

You are also responsible for filling in the postage and fee for each item. Again, you must affix the applicable First-Class postage to each mailpiece and affix postage for the total price for the service for all pieces. As of January 9, 2022, the fee for Certificate of Mailing for each piece is $0.47. Therefore, if you are mailing twenty-five pieces, you must affix postage of $11.75 to cover the applicable fees for the service provided.

Again, the USPS will confirm that all items listed on your form are in your mail and will date stamp your form as proof that they received each of those individual pieces in your mail and return it to you. It is your responsibility to keep the forms for your proof of mailing. You are allowed to create a facsimile of the form 3665 to accommodate large mailings and eliminate pages, but it must be approved by the USPS before presenting and mailing.

Bulk Certificate of Mailing
The USPS provides another product that is a more economical method to receive proof of mailing, Bulk Certificate of Mailing. This mailing service is accomplished by using USPS form 3606. With this form you provide the number of mailpieces, mailing weight and your information and affix the applicable fee for the number of pieces being presented. All mailpieces must have the applicable USPS First-Class postage affixed.
When you submit the mailing to the post office, they will validate they received the number of mailpieces listed on the form 3606. It is up to you to retain the documentation for the items presented to prove they were part of the mailing.
Only quantity received is validated when using Bulk Certificate of Mailing; you are responsible for maintaining the documentation of what was included in the mailing.

As of January 9, 2022, the cost for Bulk Certificate of Mailing is $9.35 for the first 1,000 pieces (or fraction thereof), each additional 1,000 (or fraction thereof) costs $1.20.

  • A 3,500-piece mailing would calculate as follows:
    • 1,000 @ $9.35
    • 2,500 (3, 1,000s or fraction thereof) 3 @ $1.20
    • $9.35 + $3.60 = $12.95 total fee + applicable postage for each piece
  • Comparing that same mailing as mailed Certificate of Mailing at $.47 per piece 3,500 x $.47 = $1,645
You can truly see the opportunity for savings with Bulk Certificate of Mailing. Certified Mail, Certified Mail Return Receipt and Registered Mail are the sources of Proof of Delivery.
Certified Mail

Certified Mail permits the mailer to affix the USPS form 3800 to a mailpiece with the required First-Class Mail postage and the fee for the Certified Mail service to have the ability to verify a mailpiece has been delivered or what the final disposition of the mailpiece if it was undeliverable. The form must be affixed to the top of the envelope with the dotted line folded over the envelope, being sure to not obscure the postage. The form 3800 provides a unique tracking number that can be tracked via USPS Tracking:

Tracking information is available for two years, so mailers should print delivery information for their permanent record if they feel it will be needed.

The mailpiece must be submitted to the USPS to be date stamped that the piece was received by the USPS. At that time, they should scan the barcode for the tracking number for tracking. They will tear off the perforated copy with the date stamp and return that to the mailer for their records.

The cost for Certified Mail is $3.75 plus applicable First-Class mail postage.

Certified Mail can only be used for mailing to US states, possessions, and territories.
Certified Mail Return Receipt

Return Receipt is an additional service that can be used in conjunction with Certified Mail to receive a signed document confirming receipt of a mailpiece. By affixing US form 3811 to a mailpiece with a Certified Mail form 3800 affixed as well with the form filled out on both the front and the back. The fee for the Return Receipt must be included with the total postage. As of January 9, 2022, the fee for Return Receipt is $3.05.

Total postage for Certified Mail Return Receipt:
  • One ounce First Class postage – $0.58
  • Certified Mail Fee – $3.75
  • Return Receipt Fee – $3.05
  • Total Fee – $7.38

It is important to fill out the form 3811 completely, ensuring you include all the information necessary to process the signed receipt upon return. If the mailpiece is undeliverable, the entire mailpiece will be returned to the mailer with a reason why the piece was undeliverable. Return Receipt is NOT required to mail Certified Mail, it is a separate service.

Once the mailpiece is delivered, mailers can choose to utilize Electronic Return Receipt to receive signature confirmation by email. Along with your email address, you must enter the Return Receipt tracking number on USPS tracking to request the signed Return Receipt. Large mailers who mail 25 or more Certified mailpieces per day can register for the Bulk Proof of Delivery Program and receive signature data by accessing a file provided by the USPS. Mailers interested in Bulk Proof of Delivery can access PostalPro for more details.

Registered Mail
For a mailer sending extremely important or valuable items, Registered Mail might be the right solution. All Registered Mail pieces require a signature upon delivery.
Registered Mail is the most secure United States Postal Service® mail service (Protected by safes, cages, sealed containers, locks, and keys).
Registered Mail maintains chain of control throughout the process of delivery. Delivery information provides delivery status or attempted delivery status when the item reaches its destination. Tracking is not provided as the item is enroute to its destination. To receive information concerning delivery path to destination, you must complete a claim electronically through the USPS. USPS form 3806 must be used for this service.
The fee for Registered Mail is based on the declared value of the contents. For example, $0.00 – $4,000 value, costing $13.75 and $4,001-$5000 value, costing $25.75, in addition to the required First-Class postage.
Declared Value is the actual cost of the item; a check for $25,000 is worth only the value of the paper it is printed on.
Due to the higher level of scrutiny placed on this service, it is possible that the delivery time exceeds the service level for the Class of Mail used. The USPS reserves the right to inspect the contents before authorizing use of Registered Mail.
Determining the proper mailing service to use to meet your needs for ‘Proof of Mailing’ involves ensuring the service meets your expectations and that the most cost-efficient choice for those expectations are utilized. Contacting your business partners or regulations administrators in your industry can be a first step in determining your best option.
For USPS Proof of Delivery forms, you can go to

It can be frustrating and complicated trying to navigate the best options to meet your mailing needs. If you would like to learn more about postage requirements and options that could assist your mailing needs, contact us at