Power Bank Capacity and Airline Rules
In the US, power banks go in carry-on bags only; the FAA allows up to 100 Wh, and 101 to 160 Wh with airline approval, limited to two spares.
By Giovanny CartwrightContributing writer.
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The short answer
For flights in the US, a power bank rides in the cabin with you, never in checked luggage. Its size is limited by watt hours (Wh), not by milliamp hours (mAh):
| Power bank rating | Allowed in carry-on? |
|---|---|
| Up to 100 Wh | Yes, no airline approval needed |
| 101 to 160 Wh | Only with airline approval, and at most two spares per person |
| Over 160 Wh | Above the FAA passenger limits |
These limits come from the Federal Aviation Administration (FAA). The TSA lists power banks as allowed in carry-on bags and not allowed in checked bags.
Carry-on only
The FAA treats a power bank as a spare lithium battery. Spare lithium ion batteries, including power banks and phone charging cases, must stay in carry-on baggage. If your carry-on is checked at the gate or at the plane door, take the power bank out first and keep it with you in the cabin.
The reason is fire risk. The FAA explains that any lithium ion battery can overheat in a process called thermal runaway, from damage, heat, water, overcharging or a factory defect, and flight crews are trained to deal with it in the cabin. Tell the crew at once if a battery gets hot, swells or smokes.
How to work out watt hours
Newer batteries usually print the Wh rating on the case. If yours shows only mAh, the FAA's formula is volts times amp hours. Divide mAh by 1,000 to get amp hours, then multiply by the voltage on the label.
Here is the math for a label that states 3.7 V:
| Capacity | Watt hours at 3.7 V |
|---|---|
| 10,000 mAh | 37 Wh |
| 20,000 mAh | 74 Wh |
| 27,000 mAh | 99.9 Wh |
| 30,000 mAh | 111 Wh |
| 40,000 mAh | 148 Wh |
Use the voltage your own power bank lists, since a different voltage gives a different result. On these numbers, banks up to about 27,000 mAh fall under 100 Wh, while larger ones need airline approval.
Quantity and packing
The FAA sets no quantity limit for batteries up to 100 Wh, as long as they are for your own use; batteries carried for sale are not allowed. The two-spare limit applies to the larger 101 to 160 Wh batteries.
Protect the terminals from short circuits so they cannot touch keys, coins or other metal. The FAA lists these ways:
- Keep the battery in its retail package.
- Cover the terminals with tape.
- Use a battery case or sleeve.
- Put it snugly in a plastic bag or protective pouch.
Damaged or recalled batteries cannot fly in carry-on or checked bags unless the battery has been removed or made safe.
Check your airline too
The FAA notes that many airlines, in the US and abroad, set stricter rules, including how many power banks each passenger may bring, whatever their capacity. Check your carrier's page before you pack, especially for international trips.
Where these rules come from
The limits above are from the FAA's PackSafe page on lithium batteries, last updated August 11, 2026, and the TSA's power bank entry. The watt hour table is our own arithmetic using the FAA formula.