USPS mail classes explained
What is a USPS Certificate of Mailing?
By Justin Winter · Updated August 22, 2026
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, court-admissible 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.
Common questions
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.