How to send a letter via USPS Priority Mail

Mailform is the easiest way to send USPS Priority Mail, online, right from your browser

Send Priority Letters Online Mailform

Sending a letter Priority Mail with Mailform

Mailform is the easiest way to send a letter via USPS Priority Mail online. Get USPS Priority Mail Tracking numbers quickly and easily  - we're  the easiest and fastest way to access the USPS's affordable enhanced delivery service.

Send Priority Mail Online Mailform

Here's how to send USPS Priority Mail online:

  1. First, head to, and upload your documentUpload your document
  2. Enter a destination address. This is where you want the mail to go to. Be sure to enter this clearly, - you can even use Google Maps ( to check and verify the address prior to entering it in. Enter a destination address
  3. Enter a return address. Typically a return address is where you'd like the mail to return to if, for whatever reason, the mail cannot be delivered to its destination. There are many reasons an address may be undeliverable. Those are listed at the bottom.Enter a return address
  4. Choose your printing options. Mailform has several printing options for USPS Priority Mail, including:
    1. Printing in Color: By default, we print in black and white. If you'd like your mail to be printed in color, please specify in this section. This is ideal if you're sending presentation materials or anything where color detail is important.
    2. Single Sided: By default, we print everything double sided. This means that if you're sending something that is 100 pages, it comes out to only 50 physical pages of paper, and that's all you pay for.Choose your options and select Priority Mail or Priority Mail Express
  5. Confirm your order details, including your recipient, your return address, your order details (color, sides, speed)
  6. Hit "Pay and Send". USPS Priority Mail orders placed before 10:45am EST Monday to Saturday will be mailed the same day, while orders placed on Sunday, after 10:45am EST Monday to Saturday or on USPS postal holidays will be fulfilled the next business day. 
  7. Once shipped, we'll email you with a tracking number. You can head over to to track your mail. We'll also email you a delivery notification when your mail has been delivered safely to its destination.

Email us at with questions, comments concerns or suggestions!

Some frequently asked questions are below!

When will my USPS Priority Mail Express be printed and shipped?

For early birds, we offer same day fulfillment, meaning that on most days, if your order is in before 8.45am EST, your order will be printed and shipped on the same day. After 8.45am, and on Sundays and USPS Postal Holidays, your mail will be out on the next business day:

Send Usps Priority Express Mail Online Mailform

When will my USPS Priority Mail Documents be printed and shipped?

Your print and ship time depends on when you order your mail. 10.45am EST is generally the cutoff time, and more detail is below:

Send Usps Priority Mail Online Mailform

When are the USPS Postal Holidays for 2022?

Usps Holidays Mailform


Why might mail be undeliverable?


Semantic Reason

Attempted—Not Known

Delivery attempted, addressee not known at place of address.

Box Closed—No Order*

Post office box closed for nonpayment of rent.


Used only when known that addressee is deceased and mail is not properly deliverable to another person. This endorsement must be made personally by delivery employee and under no circumstance may it be rubber-stamped. Mail addressed in care of another is marked to show which person is deceased.

Delivery Suspended to Commercial Mail Receiving Agency

Failure to comply with 508.1.8.1 through 508.1.8.3.


Address not readable.

In Dispute*

Mail returned to sender by order of chief field counsel (or under 508.1.0 and 508.2.0) because of dispute about right to delivery of mail and cannot be determined which disputing party has better right to mail.

Insufficient Address*

Mail without number, street, box number, route number, or geographical section of city or city and state omitted and correct address not known.

Moved, Left No Address

Addressee moved and filed no change-of-address order.

No Mail Receptacle*

Addressee failed to provide a receptacle for receipt of mail.

No Such Number*

Addressed to nonexistent number and correct number not known.

No Such Office in State*

Addressed to nonexistent Post Office.

No Such Street*

Addressed to nonexistent street and correct street not known.

Not Deliverable as Addressed— Unable to Forward

Mail undeliverable at address given; no change-of-address order on file; forwarding order expired.

Outside Delivery Limits*

Addressed to location outside delivery limits of Post Office of address. Hold mail for out-of-bounds customers in general delivery for specified period unless addressee filed order.


Addressee refused to accept mail or pay postage charges on it.

Returned for Better Address*

Mail of local origin incompletely addressed for distribution or delivery.

Returned for Postage

Mail without postage or indication that postage fell off.

Returned to Sender, Mailpiece Contains Nonmailable Contents.

Mail returned to sender due to contents that are nonmailable.

Returned to Sender Due to Addressee’s Violation of Postal False Representation and Lottery Law*

Mail returned to sender under false representation order and lottery order.

Returned to Sender Due to Addressee’s Violation of Postal False Representation Law*

Mail returned to sender under false representation order.

Returned to Sender Due to Addressee’s Violation of Postal Lottery Law*

Mail returned to sender under lottery order

Temporarily Away*

Addressee temporarily away and period for holding mail expired.


Addressee abandoned or failed to call for mail.

Undeliverable as Addressed, Missing PMB or # Sign

Failure to comply with 508.1.8.2e.


House, apartment, office, or building not occupied. (Use only if mail addressed “Occupant.”)



If you're looking for more resources to understand USPS Priority Mail or get your document there faster, check out the following resources:

  1. Background on USPS Priority Mail:
  2. Background on USPS Priority Mail Express:
  3. Easily print and mail your documents via Fedex:!/start
  4. (From the USPS) - A customers guide to USPS print and mail:
  5. Want to fax it instead? Check out

As always, we're here to help. Email if you have any questions!


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