USPS: Soft Packs
Print postage for USPS Soft Packs
In This Article
Soft Pack packaging is flexible and conforms to the contents so that it takes up less space and qualifies for cubic‑rate pricing. This offers a great advantage when shipping small but dense packages by lowering postage costs compared to weight‑based pricing.
In this article, we will cover:
- What is considered a ‘Soft Pack’
- The requirements for shipping a USPS Soft Pack
- How to configure a USPS Soft Pack shipment in Postsale
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 USPS Soft Pack.
Postage for USPS Soft Packs
About USPS Soft Packs
According to the USPS, a Soft Pack refers to a mailpiece prepared in flexible packaging, like a poly, plastic, vinyl, cloth, or similar soft material, that is flexible enough to adhere closely to the contents being packaged and strong enough to securely contain the contents while allowing excess air to escape.
Soft pack rates are based on cubic pricing tiers. The cubic pricing tiers are determined by the combined length and width (in inches) of the soft pack when laid flat, not on the filled total dimensions (Length, Width, and Height).
Here's a quick checklist to help you make sure that your shipment qualifies as a USPS Soft Pack:
USPS Soft Pack Requirements
- The package is made of flexible material (e.g. poly mailer, padded envelope, cloth, or soft vinyl)
- The package is not rigid and conforms to the shape of its contents
- Excess air can be compressed or pushed out of the packaging
- The weight of the package is less than 20 pounds
- The longest side (length) of the packaging is 18 inches or less when laid flat
Configure Your Soft Pack Shipment
In this section, we will look at how to configure a single shipment as a USPS Soft Pack. Check out our Ship Your Orders help article for more information on how to configure your shipments and how to print postage for multiple orders.
- Select the order you wish to ship.
- Open the Dock.
- Verify that the shipment is selected in the Shipments Grid.

- Expand the Package section if it isn't already. Then…
- Select Soft Pack from the Packaging drop-down.
- Enter the correct Weight of the package.
- Enter the Length and Width of the soft pack when laid flat.
The Height Dimension
Since Soft Pack pricing is based on the Length and Width of the packaging, no Height needs to be entered. However, if a Height was entered prior to switching the service to Soft Pack, the Height you entered is retained for you. This makes it easy to compare rates between different services..

- Use the Rate Selector to view and select from the available Soft Pack rate options.
Your shipment is now configured for USPS Soft Pack and you are ready to create and print your label.