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Certified mail forms: PS Form 3800 and 3811

Two small forms stand between you and a certified letter, and the counter is a bad place to figure them out. Here is exactly what goes in each box — and how to avoid them entirely.

The two forms, and which you need

PS Form 3800

The Certified Mail receipt. Green-and-white strip with a barcoded tracking number. Required for every certified letter. The stub you keep, postmarked by the clerk, is your proof of mailing.

PS Form 3811

The Return Receipt, the green card. Optional. Add it only when you need the recipient's signature returned to you as proof of delivery.

Neither can be printed at home — each is pre-printed with a unique barcode, so you have to collect them in person.

Filling out PS Form 3800, box by box

1

Sent To

The recipient's name or company, exactly as it should appear on the envelope. Keep it short — long names get truncated.
2

Street and Apt. No. / PO Box

Street address including suite or unit. A missing unit number is the single most common reason a certified letter fails to deliver.
3

City, State, ZIP+4

Use the ZIP+4 if you have it; it speeds up handling and reduces misroutes.
4

Extra Services boxes

Check Return Receipt only if you are also submitting a 3811. Check Restricted Delivery only if a specific named person must sign — it is an added fee most senders don't need.
5

Postage and fees

The clerk fills these in. Leave them blank.

Filling out PS Form 3811, the green card

1

Front: your own address

This is the address the signed card gets mailed back to. Getting this wrong means you never see your proof of delivery.
2

Box 1 — Article Addressed To

The recipient's full address again, matching the envelope and the 3800.
3

Box 2 — Article Number

Copy the certified tracking number from the 3800 barcode, digit for digit.
4

Box 3 — Service Type

Check Certified Mail. Add Restricted Delivery only if you also checked it on the 3800.
5

Leave the signature side blank

Boxes A, B, C and D are completed at delivery by the carrier and the recipient — not by you.

Where senders go wrong

  • Address on the 3800 doesn't match the envelope, so tracking and delivery diverge.
  • Return address on the 3811 left blank — the green card has nowhere to go back to.
  • Article number mistyped, so the receipt can't be matched to the letter.
  • Dropping the envelope in a collection box, which skips the postmarked stub you need.
  • Checking Restricted Delivery without meaning to, adding a fee and a delivery obstacle.

Or skip the forms entirely

Every field above exists so USPS can attach a barcode and a signature to your envelope. Postabl does that for you: upload your PDF, choose Certified or Certified + Return Receipt, and we generate the certified barcode, apply the forms, print, and mail the letter. You get a tracking number and a confirmation code the moment it goes out — no handwriting, no line, no lost green card in a drawer.

Pricing: certified mail cost breakdown · when you need Return Receipt

Frequently asked

What is PS Form 3800?

PS Form 3800 is the USPS Certified Mail receipt. It carries the barcoded certified tracking number, sticks to the top of the envelope, and the stub is torn off and postmarked as your proof of mailing.

What is PS Form 3811?

PS Form 3811 is the Return Receipt, commonly called the green card. It attaches to the back of the envelope, is signed by whoever accepts the letter, and is mailed back to you as proof of delivery.

Where do I get certified mail forms?

They are free at any post office counter or lobby. They are not available to print at home, because each form carries a unique pre-printed barcode. That is the main reason people end up making the trip.

Do I have to fill out forms to send certified mail?

Only if you send at the counter. When you send certified mail online through Postabl, the forms and barcodes are generated and applied for you — you upload a PDF and pay.

What is the most common mistake on the green card?

Leaving the return address on the front blank, or forgetting to check either Certified Mail or Restricted Delivery in the service boxes. An incomplete 3811 can come back unsigned or not come back at all.

We fill out the forms for you

Upload a PDF, choose certified, and we handle 3800 and 3811.

Send a certified letter