Insufficient postage surcharges such as underpaid or short paid postage refers to when you have not paid enough to cover the postage on your package.
The most common mistakes that can result in surcharges include entering incorrect package weight, package dimensions, or destination address.
Upon finding any of these issues with a package, USPS will charge the difference between the cost of the original label and what the cost should have been to the sender. The cost difference charged by the USPS will be based off of Commercial Base Pricing for everything except for Priority Mail Cubic, which will be based off Commercial Plus Pricing.
How to avoid postage surcharges:
- Weight - Make sure that you report correct weights while purchasing labels. If your package weighs 7.2 lbs, enter it as 7.2 lbs and not 7 lbs.
- When in doubt, we suggest rounding up.
- Dimensions - Report accurate dimensions when purchasing labels. Dimensional weight (volumetric weight) may apply to your packages and providing correct dimensions will help you avoid underpaid postage.
- Correct Address - Make sure that you enter the correct address and correct zip code for both the origin and destination addresses. Any discrepancies in this may result in extra charges.
- Ensure you use Flat Rate packaging only with the Flat Rate delivery service - USPS provides a wide range of shipping options to help you meet your mailing needs. Make sure that the label you are using matches the packaging. For example, if you’re using a flat rate box, you should also use a flat rate label.
For more information on how to avoid USPS surcharges you can visit this USPS guide from their website.
How Shippo will pass along surcharges:
The USPS bills Shippo for surcharges on the 10th of each month and we pass any applicable surcharge on to our customers on the 11th. Any surcharges applied to your account may be viewed within your invoices on the Billing tab.
What to do if you wish to dispute any postage surcharges:
If you believe that you were incorrectly charged for an insufficient postage surcharge from the USPS, you must contact us and provide details about the disputed shipment (tracking number, dimensions, weight, delivery information, and proof of which label was used). We will then contact the USPS on your behalf. Please note: it can take up to several months for USPS to process any dispute and associated refund and this is completely outside of Shippo's control.