How Do I Send Priority Mail (Flat Rate Mailing Envelope)?

By Jay White

May 15, 2014   •   Fact checked by Dumb Little Man

Sending a Priority Mail flat-rate envelope requires the use of specific materials that are free from the United States Postal Service (USPS). You can get the supplies at any USPS office or you can request free supplies online from the USPS website, Priority Mail envelopes are made from a synthetic source trade-marked as Tyvek, see, are 9-1/2” x 12-1/2” in size, and are available in free packs of 5, 10, or 15 and in pre-paid packs of 5, 10 or 25. You can use a flat-rate envelope for any item that easily fits inside, weighs 4 pounds or less, and the flap can close naturally.

Preparing the Envelope:

1. To prepare a flat rate envelope at home, you will need to use a credit card to prepay the Priority Mail flat fee and to print out a postage label plus a shipping label. If you do not have self-sticking labels, use paper labels and attach them to the envelope with clear shipping tape. You can schedule a pick up by the USPS.

2. If you prefer, or require, the assistance of a postal clerk; you can take the material to be mailed to a USPS building and prepare a Priority Mail flat rate envelope with the label information at the Post Office counter.

Highlights of Priority Mail Flat Rate Shipping:

1. An envelope is delivered in two to three days when mailed to a domestic address.

2. An envelope is delivered in three to ten days when mailed to an address outside of the United States.

3. An envelope mailed to a US address is $4.90, the cost is $11.45 for an address in Canada or Mexico, and the cost is $13.45 for another international address.

4. Priority Mail flat rate envelopes sent to APO/FPO military addresses are priced at the domestic rate.

Priority Mail Flat Rate Shipping Options:

In addition to the flat rate cost, the USPS has extra options available for added fees. Some of the services include a Certificate of Mailing, Certified Mail Service, Insurance, Registered Mail, Signature Confirmation, and Special Handling. A full listing of priority mailing options and the added costs can be viewed at

When compared to using certified or registered regular mail, you will save money using a Priority Mail flat-rate envelope for important documents or for an item that weighs more than a few ounces.

Jay White

I started Dumb Little Man many years ago so great authors, writers and bloggers could share their life "hacks" and tips for success with everyone. I hope you find something you like!

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