Ship USPS limited-quantity hazmat and print the "H" on the label

Summary: To ship USPS limited-quantity hazmat through Endicia, set up the hazmat item in the Item Book, add it to the shipment, and confirm USPS has approved your account for limited quantities. The required "H" marking now prints on the Endicia label on current releases.

Before you start

Your USPS account must be approved by USPS to ship limited quantities. Check with your USPS representative.
You ship USPS through the Endicia integration.
Your Shipstore site is on a current release (mid-2026 or later), which added hazmat support to Endicia so the label prints the "H".

Steps

In the Item Book, create or edit the hazmat item and fill in its required hazmat fields.
Add that hazmat item to the shipment from the Item Book.
Process the shipment.
Check the label for the hazmat "H" marking.

What you should see

A limited-quantity hazmat shipment produces a USPS/Endicia label that shows the "H" marking, and the hazmat item and its fields are on the shipment.

If something goes wrong

The "H" does not print on a current release: email support@shipstore.com and ask us to check the Endicia hazmat setup for your account. Include your company name.

USPS rejects the shipment: confirm USPS has approved your account to ship limited quantities.

Switch to a hazmat profile automatically with a child rule

Knowledge Base