Power banks and flying: how many mAh can you take?

The rule is simple: up to 100 Wh needs no approval, and it is worked out from the mAh, not from the size. Here is the formula and a ready table for the most common capacities.

Every week someone asks us: "My power bank is 20,000 mAh, will it get through the airport?" The answer is yes, but not because of the number printed on it. Airlines don't count in milliamp-hours at all. They count in watt-hours (Wh).

The rule in short

  • Under 100 Wh: allowed, no approval needed.
  • 100 to 160 Wh: needs airline approval, and usually limited to two units.
  • Over 160 Wh: not allowed, neither in the cabin nor in checked baggage.

The most important part: never in checked baggage

This is where most people slip up. A power bank has to travel with you in your carry-on, inside the cabin. It is strictly banned from the bag that goes in the hold. The reason is simple: if a lithium battery ever has a problem, someone needs to notice it fast, and that is impossible in the cargo hold.

How to calculate it yourself

The formula is easy. Power banks are rated at 3.7 volts:

Wh = (mAh ÷ 1000) × 3.7

So a 20,000 mAh power bank is (20000 ÷ 1000) × 3.7 = 74 Wh, comfortably under the 100 Wh limit.

Ready table for common capacities

CapacityWatt-hoursStatus
5,000 mAh18.5 WhAllowed
10,000 mAh37 WhAllowed
20,000 mAh74 WhAllowed
26,800 mAh99 WhAllowed, right at the limit
30,000 mAh111 WhNeeds prior approval
50,000 mAh185 WhNot allowed

Our advice

If you travel often, get a 20,000 mAh power bank and stop worrying. It charges a phone two to three times, and no airport officer will stop you for it. Anything above about 27,000 mAh becomes more hassle than it is worth, unless you are running a laptop off it.

One more thing: some power banks don't print the Wh figure clearly. If the number isn't on the body of the unit itself, there is a real chance it gets held at security, so choose a known brand with clear labelling.

Before you fly

Rules vary between airlines and change from time to time, so always check the baggage page on your airline's website the day before you travel. What is above is the international standard that most carriers follow.

You will find power banks of every capacity, all clearly labelled, in our chargers section and our travel section.