As of 3 November 2026, the short answer is this: a power bank goes in your cabin bag, never in checked luggage; the international rules allow two at most, but some airlines, including EgyptAir and Emirates, allow only one; it should be rated 100 Wh or less (about 27,000 mAh at 3.7 V); and you must not recharge it on board. Many airlines go further and do not let you use a power bank at all during the flight. The rules changed in March 2026 and each airline applies them in its own way, so your airline's own page always has the final word.
What changed in 2026
On 27 March 2026 the International Civil Aviation Organization (ICAO) published Addendum No. 1 to its Technical Instructions for the Safe Transport of Dangerous Goods by Air, the rules that airline dangerous-goods policies are built on. It applied from the same day. It separates power banks from other spare batteries and says that power banks:
- must be carried in cabin baggage;
- must not be recharged while on board;
- should not be used to recharge a phone or other device while on board;
- are limited to two per person;
- must be protected against short circuits when not in use.
IATA, the airline industry body, says these changes will be written into the 68th edition of its Dangerous Goods Regulations, which applies from 1 January 2027, and that each country puts them into force through its own legal process. Some regulators, such as the UK Civil Aviation Authority, applied them from 27 March 2026. Airlines are also free to be stricter than this baseline, and many are.
Watt-hours: the number that decides
Airlines judge a power bank by its energy in watt-hours (Wh), not by mAh. If the label shows only mAh, multiply it by the battery voltage printed on the label and divide by 1,000: a 20,000 mAh bank at 3.7 V is 74 Wh. Use the battery voltage, not the 5 V USB output. IATA notes that if staff cannot verify the Wh rating from the battery or its documentation, the airline may refuse to carry it, so a bank with a worn or missing label can be stopped at the gate.