How do I use USPS Soft Pack Envelopes for Cubic Pricing?

Determining cubic tier measurements for Soft Pack Envelopes goes as follows:

  1. Measure the length and width separately in inches
  2. Round down your measurements to the nearest 1/4 inch. For instance, a measurement of 10 1/8 inches is rounded down to 10 inches.
  3. Add the two measurements. In order to qualify for cubic pricing, the total cannot exceed 36 inches.

Assuming your package’s length/width total is 36" or under, the table below determines the Cubic Pricing tier your Soft Pack Envelope package falls under.

Cubic Price TiersLength + Width
0.10Mailpieces measuring from 0" up to 21"
0.20Mailpieces measuring more than 21" up to 27"
0.30Mailpieces measuring more than 27" up to 31"
0.40Mailpieces measuring more than 31" up to 34"
0.50Mailpieces measuring more than 34" up to 36"
Don't see your question? Talk to a shipping expert