How to Send a Self-Addressed Stamped Envelope

You need two envelopes

In the mail industry we abbreviate this SASE. The idea is really straightforward: when you send someone a letter, you provide them an envelope to return mail in, with postage already on it.

You'll see a similar idea sometimes with product paperwork, as you see in our main image. We bought a crib for a baby and it came with a registration card we could mail back for safety alerts or recalls. That card says “No postage necessary,” so the company pays for the reply. With a SASE, you provide the return postage yourself.

So if you're sending your own, then you need to have two envelopes. One addressed to the recipient, and one addressed back to yourself. The envelope addressed back to yourself should be stamped and put in the envelope that is sent to the other person.

1. Address the return envelope to yourself

Write your name and mailing address in the delivery-address area, in the middle of the envelope. This is where the reply needs to go. Add the return postage in the upper-right corner.

Follow any instructions about the upper-left return-address area. Put your address in the middle of this inner envelope, not the organization's address.

Leave it unsealed. The recipient needs to put your reply inside before closing it.

2. Put it inside the envelope you are sending

Put your request and the unsealed return envelope inside the outer envelope. A slightly larger outer envelope makes this easier. Only fold the return envelope if the recipient's instructions allow it.

Address the outer envelope normally: their name and address in the center, your return address at the upper left, and outgoing postage at the upper right. Then seal the outer envelope.

For placement examples, see how to address an envelope.

3. Pay for both trips

The stamp on the inner envelope pays for the reply. It does not pay for sending the outer envelope.

Do not assume two Forever stamps will always cover everything. The outer envelope includes your request and the return envelope. The return envelope needs enough postage for the item coming back, not just the empty envelope.

If you do not know the reply's weight or size, ask the recipient what postage to include. You can check a known weight with the postage calculator.

If the reply will be mailed from another country, ask for that recipient's return-postage instructions. USPS stamps generally cannot pay for postage originating in a foreign postal system.

Does every return envelope need a stamp?

No. Check what is printed on it. These two examples show the difference.

A simple example

An organization asks you to mail a request and include a SASE so it can send a paper reply. On the small envelope, you write your own address, add the requested return postage, and leave the flap open.

You put that envelope and your request inside a larger envelope addressed to the organization. You add postage for the full outgoing mailing and seal it. They open the outer envelope, put the reply in your return envelope, seal it, and mail it back.

Quick check before sealing the outer envelope

• The inner envelope has your address in the middle.
• The inner envelope is unsealed and large enough for the reply.
• You included the return postage the recipient needs.
• The outer envelope has their address and its own postage.
• Your request and any required forms are inside.