USPS: Letters & Flats

Quickly purchase and print postage for your domestic First Class letters and flats with Postsale's built-in USPS integration. Depending on what fits your workflow best, you can choose to print on standard 4" x 6" or compact 2" x 1.5" labels.

In this article, we will look at:

• The differences between letters and flats
• Printing to 4" x 6" vs. 2" x 1.5" label stock
• Weight and dimension requirements for letters and for flats
• How to configure a shipment to print postage for letters and flats
• Non-machinable options

Before We Begin

This article assumes that you have added your USPS account to Postsale and that you have orders imported into Postsale that you wish to ship as a First Class Letter or Flat.

Postage for Letters & Flats