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At the post office counter, ask for Certified Mail and add a Return Receipt if you want proof of delivery with a signature. Keep the mailing receipt: its tracking number proves you sent it. The carrier gets a signature on delivery and makes repeated attempts before leaving a pickup notice.
Bring your addressed, sealed envelope. Tell the clerk you want Certified Mail, which is an extra service added to First-Class or Priority Mail. The clerk attaches the certified label, weighs the envelope if needed, and hands you a mailing receipt with a tracking number starting in 9407. That receipt is your proof of mailing; file it somewhere you can find it, because it is the document courts and agencies ask about.
One thing people misunderstand: Certified Mail by itself does not include the green card. The green card, the Return Receipt (PS Form 3811), is a separate add-on that comes back to you with the recipient's signature and delivery date. If your goal is proving the other party received it, ask for the Return Receipt too. You can choose the traditional green card mailed back to you or the electronic version, where you view and print the signature from the USPS tracking site.
| Option at the counter | What you get |
|---|---|
| Certified Mail alone | Proof of mailing plus tracking and a delivery signature on file. You can look up the delivery record online. |
| Certified Mail + Return Receipt (green card) | Everything above, plus a physical card mailed back with the recipient's signature and the date of delivery. |
| Certified Mail + Electronic Return Receipt | The same proof, delivered as a printable image of the signature instead of a card in the mail. |
| Restricted Delivery (add-on) | Only the named addressee or their authorized agent can sign for it. Useful for legal notices. |
The carrier attempts delivery in person and collects a signature. If nobody is available, the carrier leaves a notice and holds the piece at the post office, then makes another attempt. After the final attempt, the item waits at the counter for pickup for a set period before being returned to you as unclaimed. Each attempt is logged against the tracking number, so the record shows a genuine effort to deliver, not a single knock.
They solve different problems. Certified Mail is the standard choice for proof of mailing and delivery: tax filings, contract notices, landlord letters. Registered Mail is the maximum-security option, with a documented chain of custody at every handoff; use it for irreplaceable originals. The Return Receipt is not a mail class at all, just the proof-of-delivery add-on that rides on top of either. For most legal deadlines, Certified Mail with a Return Receipt is the sweet spot: it proves you mailed it and proves they got it.
Three things. The mailing receipt with the tracking number, which proves the piece entered the mail stream on a specific date. The Return Receipt, green card or electronic, which proves who signed and when. And a copy of what you sent, ideally with the date on it. Together these answer every question a court, agency, or contract counterparty can ask: when did you send it, what did you send, and who received it.
Yes. Ordering through an online service gets you the same Certified Mail product: the piece is printed, mailed, and tracked, and you receive the tracking and delivery records. LetterAgent offers a certified option on letters, with tracking plus proof of delivery. See our certified vs registered vs regular mail comparison for how the options differ.
Ready to mail it? Send your letter with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is printed and mailed.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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