Free guide · updated October 2026
Is my product hazmat? A plain-English guide for Shopify sellers
Plenty of everyday products are hazardous materials in shipping terms. If you sell any of the five below, you probably need to declare them when you buy a label, and most can only travel by ground.
The five most common "accidental hazmat" products
| Product | Hazard class | Typical UN number | USPS |
|---|---|---|---|
| Alcohol-based perfume, cologne, aftershave | Class 3, flammable liquid | UN1266Perfumery products | Ground only |
| Nail polish | Class 3, flammable liquid | Often UN1263Paint; varies by formula | Ground only, as a consumer commodity |
| Aerosols: hairspray, dry shampoo, spray deodorant | Class 2, gas | UN1950Aerosols | Ground only, as a consumer commodity |
| Alcohol hand sanitizer | Class 3, flammable liquid | Often UN1987Alcohols, n.o.s. | Ground only |
| Lithium batteries, alone or in devices | Class 9, miscellaneous | UN3480 / UN3481Lithium ion; UN3090 / UN3091 for lithium metal | Loose lithium-ion batteries (UN3480) are ground only; rules depend on battery size and packing |
"Typical" means common, not guaranteed. Your product's own safety data sheet decides. Sources: Stamps.com, The Compliance Center on UN1263, Lion on hand sanitizer, USPS Postal Bulletin, USPS Publication 52.
How to check any product in four steps
- 01
Get the SDS
Ask your supplier or manufacturer for the safety data sheet. Most post it online: search the brand, product name and "SDS".
- 02
Go to Section 14
"Transport information" is where shipping classification lives. Ignore the rest for now.
- 03
Write down four things
UN number, proper shipping name, hazard class and packing group. If it says "not regulated", it isn't hazmat for transport.
- 04
Declare it on the label
Tick the hazmat box when you buy the label, pick a ground service, and mark the box as the carrier requires.
Why it matters more in 2026
Since July 12, 2026, USPS charges a $7.50 handling fee on declared hazmat sent Priority Mail and a $50 fee on any commercial package found with undeclared hazmat (ship.com). Getting it wrong can also get your carrier account suspended, which stops all your shipping. And Shopify Shipping doesn't support hazmat labels at all (Shopify).
Got 50 products to check?
HazFlag does these four steps for your whole catalog inside Shopify. Join the waitlist for free early access and a manual catalog review.
This guide is general information, not legal or compliance advice. Hazmat rules depend on the exact formula, quantity, packaging and carrier. Check the U.S. DOT Hazardous Materials Regulations (49 CFR Parts 171 to 180), USPS Publication 52 and your carrier's rules before you ship. Anyone who prepares hazmat shipments needs DOT hazmat training; PHMSA offers free modules.