Power banks on a plane: what the rules say

Power banks are allowed on US flights, but only in your carry-on, and only up to a certain size. The size is measured in watt-hours, printed on the label on the case. Here is what the FAA and TSA rules say, how to work out the watt-hours when the label shows only milliamp-hours, and what to do at the gate.

The limits

A power bank counts as a spare lithium-ion battery. Spare lithium batteries are never allowed in checked bags, because a fire in the hold is much harder to deal with than one in the cabin. In your carry-on, the rules depend on capacity:

Capacity	Carry-on	Checked bag
Up to 100 Wh	Allowed, no approval needed	Not allowed
101–160 Wh	With airline approval, up to two spares	Not allowed
Over 160 Wh	Not allowed	Not allowed

Almost every phone and laptop power bank sits in the first row. The second row covers large camera and drone batteries, and the approval has to come from the airline before you fly, not from the security officer at the checkpoint.

From mAh to Wh

Many power banks print their capacity in milliamp-hours. To convert, multiply by the cell voltage, 3.7 V for lithium-ion, and divide by 1,000: Wh = mAh × 3.7 V / 1000.

• 10,000 mAh: 37 Wh
• 20,000 mAh: 74 Wh, the size of Cell 20
• 26,800 mAh: 99 Wh, the largest that needs no approval
• 30,000 mAh: 111 Wh, airline approval required
• 50,000 mAh: 185 Wh, not allowed on board

Whatever the capacity, the label matters. A power bank with no readable rating on the case may be refused at security, so keep the label clean and do not cover it with stickers. Cell 20 has both figures, 20,000 mAh and 74 Wh, printed on the case.

Packing and at the gate

Pack the power bank in a pouch or a pocket where the ports cannot touch keys or coins. If the gate agent asks to check your carry-on because the overhead bins are full, take the power bank out first and keep it with you. The same goes for a spare laptop battery.

Batteries built into devices follow gentler rules. A laptop, headphones such as Arc ANC or an earbud case may travel in a checked bag if they are switched fully off and cannot turn on by accident. We still keep them in the cabin: a bag can be lost, and a cabin crew can deal with a battery that overheats. Only the power bank itself has no choice.

“We built Cell 20 to 74 Wh on purpose: enough to charge most 13″ laptops once, or a phone about four times, and well inside the limit, so nobody has to explain it at security.”

Daniel Reyes, head of product

Rules change, and airlines can be stricter than the FAA. Some now ban charging from a power bank during the flight or ask you to keep it in view, so check with your airline before you fly, especially on international routes.

Chargers and cables have no limits, so a Brick 65 and a Link USB-C cable can go in any bag. For the rest of the pouch, see our travel packing list.