USPS Cubic Pricing in ShipStation

USPS cubic pricing is available by default when creating labels in ShipStation.

Cubic rates are ideal for small, heavy packages since the pricing is based on the volume of the package instead of the weight. Any package that measures 0.50 cubic feet or less and is 20 pounds or less is eligible.

To receive cubic rates in ShipStation:

  1. Choose USPS Parcel Select Ground or a domestic Priority service.

  2. Choose a package type of Package.

  3. Enter the package weight & dimensions.

ShipStation will automatically apply the cubic rate whenever it's cheaper than the priority rate.

Cubic Pricing for Softpacks

USPS offers a special cubic rate option for a package type called Softpack or Polybag. These package types are not yet available in ShipStation, but we plan to make them available in the future.

If you wish to ship using ShipStation Softpacks, please contact ShipStation support to enable this feature for you.

Once enabled, the following steps will allow you to view the appropriate cubic rate for Softpack or Polybag shipments.

Softpack Pricing Requirements

  • The mail piece must be 20 lbs or less.

  • The longest dimension cannot exceed 18 inches.

  • Must be .50 cubic feet or less. The following list provides Length + Width for each tier of Cubic Softpack Pricing:

    • 0.1 - Length + Width between 0" and 21"

    • 0.2 - Length + Width between 21" and 27"

    • 0.3 - Length + Width between 27" and 31"

    • 0.4 - Length + Width between 31" and 34"

    • 0.5 - Length + Width between 34" and 36"

  • May not be in rolls or tubes.

To View Appropriate Rates

  1. Select your order from the Orders grid and choose USPS Priority Mail or Parcel Select Ground as the shipping service.

  2. Set packaging type to Large Envelope or Flat.

  3. Enter the weight of the shipment.

  4. Enter the length and width, but leave the height field blank.

This will fetch the tiered cubic rate for the product, should it meet the requirements for cubic rates.