Fill out the form
PS Form 3817 is a small slip a clerk hands over on request. Write the sender, recipient and the mail class, and hand it back with the piece being mailed.
USPS Form 3817
What PS Form 3817 does and does not prove
PS Form 3817 is a Certificate of Mailing: a receipt USPS postmarks at the counter that proves a specific piece of mail was accepted on a specific date. It does not track the piece, it does not confirm delivery and USPS does not keep a copy. The current fee is $2.45 per article. Rules from DMM 503 and fee from Notice 123, both read 2026-08-11.
The rule in one sentence
The Domestic Mail Manual describes the form directly:
“Certificates of Mailing provide evidence that individual mailpieces have been presented to the USPS for mailing. Certificates of Mailing do not provide a record of delivery, and the Postal Service does not retain copies of either form.”
DMM 503.5, pe.usps.com, read 2026-08-11
Two practical points. The certificate proves acceptance on the postmark date, and only that. And because USPS keeps no copy, the postmarked slip in your possession is the record - lose it and the proof is gone.
Buying one at the counter
Pay the fee and take the receipt
$2.45 per article, per USPS Notice 123 effective 2026-07-12 and read 2026-08-11. The clerk applies a round-dater postmark to the form and returns it. That postmarked slip is your evidence.
Bulk certificates
For a batch, PS Form 3877 lists many pieces on one form and takes a firm-mailing bill discount. Available to any mailer with three or more pieces at once. USPS Notice 123 lists a lower per-piece fee for the firm certificate.
When Form 3817 is the right tool
Certificate of Mailing exists for one job: proving a deadline was met by depositing the piece with USPS on time. It sits below Certified Mail in cost, and below Registered Mail in security, because it is doing less.
| Question | Certificate of Mailing | Certified Mail |
|---|---|---|
| Proof piece was accepted | Yes, on the postmark date | Yes, and it produces a barcode |
| Delivery scanned | No | Yes, and events post on tools.usps.com |
| Signature captured | No | Yes when combined with Return Receipt |
| USPS keeps a copy | No | Yes, delivery record retained for two years |
| Current fee | $2.45 | Higher - see Notice 123 |
A tax return or a legal document filed by mail on the last day of a filing window is the textbook use. The postmark on Form 3817 is enough to satisfy an on-time filing dispute later. When the recipient can also lose the letter, upgrade to Certified with Return Receipt.
Where a sender can slip up
The receipt is the evidence, not the mailing. A postmarked 3817 that has been thrown away in a filing cull has no back-up copy at any post office. Scan it and store the image the same day. A drop-in-the-blue-box mailing cannot use a Certificate of Mailing - the counter must postmark the slip, so the trip to the counter is the point.
Sources
- USPS, DMM 503 Extra Services - Certificate of Mailing definition and rules (503.5). Read 2026-08-11.
- USPS, Notice 123 Price List - PS Form 3817 fee of $2.45, effective 2026-07-12. Read 2026-08-11.
Common questions
What is PS Form 3817?
A Certificate of Mailing - a small USPS receipt postmarked at the counter to prove a specific mailpiece was accepted on a specific date. It does not track the piece.
How much does a Certificate of Mailing cost?
$2.45 per article at the counter, per USPS Notice 123 effective 2026-07-12.
Does USPS keep a copy of my 3817?
No. The DMM says the Postal Service does not retain a copy. The postmarked slip in your possession is the only record.
When should I use it instead of Certified Mail?
When you only need proof the piece was mailed on time and do not need delivery tracking or a signature. It is much cheaper than Certified.
Can I get a Certificate of Mailing on a package dropped in the blue box?
No. The postmark must be applied by a clerk, so the piece has to be presented at the counter.