GLOSSARY
PS Form 3800
By Justin Winter · Updated August 28, 2026
The USPS Certified Mail receipt form — the green-and-white strip carrying the tracking number that you keep as proof of mailing.
PS Form 3800 is the Certified Mail receipt. At a post office counter you fill in the recipient, peel the barcoded portion onto the envelope, and the clerk postmarks the stub you keep. That postmarked stub is the artifact people mean when they say they have proof of mailing.
Sending Certified Mail online produces the same tracking number and the same USPS record without the paper form — the receipt is the order record and the tracking history instead.
See also
- PS Form 3811 — The paper return receipt — the "green card" that is signed at delivery and mailed back to the sender.
- Certified Mail — A USPS extra service that adds a dated mailing receipt and delivery tracking to a letter, with the delivery record kept by USPS.
- Proof of mailing — Documentation that a piece of mail was handed to USPS on a given date — the sending half of the evidence, not the delivery half.
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