The mark is standard worldwide. The number printed inside it is the part that has to match what is in your box.
Four numbers, one decision
Two questions settle which code applies: what chemistry the cell uses, and whether it travels with its equipment.
| UN number | What it covers | Everyday examples | Excepted ceiling |
|---|---|---|---|
| UN3480 | Lithium ion cells and batteries shipped by themselves | Power bank, spare tool pack, replacement phone battery | 20 Wh per cell, 100 Wh per battery |
| UN3481 | Lithium ion batteries contained in, or packed with, equipment | Phone, laptop, camera, drone, cordless drill | Same watt-hour ceilings, with equipment packing rules |
| UN3090 | Lithium metal cells and batteries shipped by themselves | Non-rechargeable camera and watch cells | 1 g lithium per cell, 2 g per battery |
| UN3091 | Lithium metal batteries contained in, or packed with, equipment | Devices running on primary lithium cells | Same gram limits, with equipment packing rules |
That printed rating on the case is what makes this checkable at home. A laptop pack marked 56 Wh sits comfortably inside the ceiling; an electric bike pack marked 500 Wh does not, and no self-service checkout can carry it.
Package limits and the mark itself
The exception that lets ordinary lithium shipments move without full dangerous goods paperwork comes with numbers attached, and they are specific.
The symbols and letters are black on white or another contrasting background and the hatching is red, with the asterisk on the printed mark replaced by the UN number that applies. Packages are also required to survive a 1.2 meter drop in any orientation without the cells shifting into contact or the contents escaping, which is the real argument for a rigid inner box rather than a padded envelope.
One exemption is worth knowing: the mark is not required when a package holds only button cells installed in equipment, or when a consignment is two packages or fewer and each holds no more than four cells or two batteries contained in equipment.
The ground-only uprate, and what shipping costs
There is a second tier most guides never mention, and it exists precisely because road transport tolerates more than aircraft do.
A 300 Wh ceiling on the road against 100 Wh in the air is a threefold difference, and it explains why so many battery shipments quote with ground services only. The trade is a stricter marking and no aircraft, ever.
| Carrier | Service | Price | Transit window returned |
|---|---|---|---|
| UPS | Ground Saver | $19.14 | Not returned for this row |
| UPS | Ground | $19.30 | 6-7 business days |
| USPS | Ground Advantage | $19.64 | 5-6 business days |
| FedEx | Ground Economy | $20.50 | 7-8 business days |
| UPS | 2nd Day Air | $31.43 | 2-3 business days |
The air row at the bottom is there because that quote carried no battery. Declare a power bank and the list that returns holds ground services alone, which is the enforcement working rather than a shortage of options.
Alone or installed changes everything
A battery inside the device it powers is protected by that device and is treated more gently by the rules, which is why UN3481 shipments face fewer conditions than UN3480 ones. Fitting a spare pack into the tool before boxing it is a legitimate way to change which code applies.
Watt-hours, not milliamp-hours
Consumer packaging advertises mAh, while the regulation works in watt-hours. Multiply amp-hours by the nominal voltage to convert: a 10,000 mAh pack at 3.7 volts is 37 Wh, comfortably under the 100 Wh line.
Damaged cells have no lane at all
Swollen, leaking, recalled or fire-damaged batteries are outside every exception described here. No UN number, mark or service makes them shippable through a self-service checkout, ours included, and our restrictions policy says so directly.
UN3480 questions
What does UN3480 mean?
It identifies lithium ion cells and batteries shipped on their own, without equipment in the package. Power banks, spare tool packs and replacement phone batteries all ship under that number.
What is the difference between UN3480 and UN3481?
The equipment. UN3481 covers lithium ion batteries contained in, or packed with, the equipment they power, while UN3480 is for batteries travelling alone. The lithium metal equivalents are UN3090 and UN3091.
What are the watt-hour limits?
For excepted shipments, 20 Wh for a lithium ion cell and 100 Wh for a lithium ion battery, per 49 CFR 173.185(c)(1)(i). Highway and rail transport allows 60 Wh per cell and 300 Wh per battery with a stricter marking on the box.
How large must the lithium battery mark be?
Not less than 100 mm wide by 100 mm high, with hatching at least 5 mm wide. A reduced mark of 100 mm by 70 mm is allowed when the package is too small for the full size.