i phone picture a day: New USPS HAZMAT label fee: what sellers should know.

Fees for incorrect HAZMAT labels

Hi blrnz.ppd,

On July 12, 2026, USPS introduced non-compliance fees for improper handling of Hazardous Materials (HAZMAT) labels on domestic packages. Specifically, USPS now applies a $50 fee when a non-HAZMAT item is shipped in a box that carries a visible HAZMAT label, as these packages require special handling.

Effective September 1, 2026, the cost of this fee will be shared between the seller and Mercari: Mercari will cover $25, and the remaining $25 will be charged to the seller. Packages postmarked prior to September 1, 2026 will be exempt from the seller charge.

As long as your packages are properly labeled this fee will not apply. To learn more about Mercari’s policy on shipping hazardous items and whether your package is impacted, please review our Help Center.

What you need to know:

	Correctly labeled HAZMAT packages will not be impacted by this change.
	Beginning September 1, 2026, sellers will be charged a $25 fee applied to packages that include a HAZMAT label but don’t contain Hazmat items. Mercari will cover the remainder of the fee charged by USPS.
	If you plan to reuse packaging materials, make sure any old HAZMAT labels are completely removed or blotted out so none remain visible.