When your package is large but not that heavy, it could get charged based on the dimensional weight (or DIM weight) instead of the actual weight 🙈 This can typically happen when you're shipping items like pillows, wreaths, or a handbag.

DIM weight can apply to any package that is larger than 1 cubic foot (for example, if the dimensions are 13x13x13" or larger) and is being shipped to zones 5-9. These surcharges will apply only to weight-based Priority Mail, Priority Mail Express, and Parcel Select Ground 👍

Calculating DIM weight

To determine if DIM weight pricing will apply to your shipment, multiply the Length * Width * Height of your shipment, and divide that total by 166 ✏️ If the number you get is higher than the actual weight of your shipment, USPS will use that number as the "dimensional weight" of your package when determining the cost of postage.

A quick example

Let's imagine we've got a box measuring 26x26x5" that weighs 3 lbs, being sent from New York to Los Angeles. The Priority Mail rate for this shipment would cost $65.22 😮

  • By multiplying the dimensions (26 * 26 * 5), the total we get is 3,380
  • When dividing 3,380 by 166, we receive a total of 20.4
  • Because 20.4 is higher than the original weight of 3 lbs, USPS will calculate the rate of this shipment as if it weighed 20.4 lbs

How can I avoid DIM weight pricing?

USPS no longer offers a way to avoid those dimensional weight surcharges, even if you choose to ship directly from the Post Office 😥 However, there are still ways to help reduce your cost to ship!

  • Use the smallest packaging possible for the item you're sending
  • See if you can cut your box down to a smaller size
  • If possible, separate the items being sent into multiple, smaller shipments
  • If the box can fit inside of an envelope or poly mailer with room to spare, see if you can find a lower rate through the "box in a bag" trick

Still sailin' in murky waters? Our support team is happy to help 😃

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