USPS mail classes explained
What is a USPS Certificate of Mailing?
By Justin Winter · Updated August 22, 2026
The short answer
A USPS Certificate of Mailing (Form 3817) is a $1.85 receipt that proves you mailed something on a specific date — nothing more. It does not track the piece and does not prove it was delivered; if you need that, you need Certified Mail, which paperplane sends online for $12.99.
USPS Notice 123 lists it as a real, separate service: a Certificate of Mailing (PS Form 3817) is a receipt, stamped and dated by a retail clerk, that says you mailed a particular piece on a particular day. That's it. It doesn't generate a tracking number, it doesn't get scanned again in transit, and it says nothing about whether the piece was ever delivered.
Most people who search for this are trying to solve a proof-of-delivery problem — a dispute, a notice, a legal deadline — and a Certificate of Mailing usually isn't the tool for that, even though it sounds like it should be. This page is not legal advice; if a deadline or notice requirement is on the line, check the exact wording of the statute, contract, or court rule before choosing a mail class.
Certificate of Mailing vs. Certified Mail vs. Certified + Return Receipt
| Service | Proves mailing date? | Trackable? | Proves delivery? | Cost |
|---|---|---|---|---|
| Certificate of Mailing | Yes | No | No | $1.85 (USPS counter only) |
| Certified Mail | Yes | Yes, USPS tracking number | No (delivery scan only, no signature by default) | $12.99 all-in with paperplane |
| Certified + electronic Return Receipt | Yes | Yes | Yes, a signed USPS delivery record | $14.99 all-in with paperplane |
Why Certified Mail is usually the better default
A Certificate of Mailing is cheaper, but it only helps if the only thing ever in question is the date you dropped something in the mail — and it requires a trip to a USPS counter, since it isn't something you can generate online. Certified Mail costs more but gives you a tracking number you can check yourself at any point, plus a mailing record, and you can do the whole thing from your phone. If there's any chance you'll need to show what happened to a letter after you sent it — not just that you sent it — Certified Mail is the safer default, and Certified + Return Receipt is the strongest one.
See what Certified Mail actually is, how it compares to Registered Mail and Priority Mail, or the full cost breakdown.
Questions before you send
Is a Certificate of Mailing the same thing as Certified Mail?
No. A Certificate of Mailing only proves the date you handed something to USPS. Certified Mail adds a tracking number, so you (and, if needed, a court or agency) can also see when and confirm that it moved through the mail. They solve different problems.
Does a Certificate of Mailing prove my letter was delivered?
No — that is the most common misunderstanding about it. It proves mailing, not delivery. For delivery proof you need Certified Mail with electronic Return Receipt, which captures a signature or delivery confirmation.
When is a Certificate of Mailing actually enough?
When a deadline only requires proof you sent something by a certain date — some tax filings and contract notices work this way — and you do not need to know or prove what happened to it after that. Read the actual statute or contract clause first; many that say "certified mail" or "proof of delivery" will not accept a Certificate of Mailing alone.
Can I get a Certificate of Mailing through paperplane?
Not as its own product today — we do not currently sell the standalone USPS Certificate of Mailing (Form 3817). Our closest match is Certified Mail at $12.99, which gives you tracking plus proof of mailing, or add electronic Return Receipt for $14.99 if you need proof of delivery too. If a plain Certificate of Mailing is genuinely all you need, USPS sells it at the counter for $1.85.