On 27 March 2026, the International Civil Aviation Organization (ICAO) began applying an addendum that limits each passenger to two power banks and prohibits recharging a power bank during a flight. For you, a bank you flew with last year may now break your airline's count or use rules. US federal rules are looser than many airline policies, so the airline's page is the rule you actually fly under.
Key takeaways
- Spare lithium-ion batteries and power banks go in carry-on bags only. Under the federal rule, banks of 100 Wh or less need no approval, up to two banks of 101-160 Wh need airline approval, and nothing above 160 Wh is allowed in baggage.
- Watt-hours equal milliamp-hours times the nominal voltage divided by 1,000. Assuming 3.7 V, a 26,800 mAh bank works out to 99.16 Wh, just under the 100 Wh line.
- ICAO caps passengers at two power banks and bans recharging them on board; charging a phone from one is only discouraged. Airlines go further: Southwest allows one bank, and Emirates allows one and bans all use.
What it means for you
- US domestic flyers: federal rules set the Wh ceilings; your airline sets count, storage and use.
- Flying to or within Asia: Singapore Airlines and the Korean carriers ban charging devices from a power bank in flight.
- Owners of 100-160 Wh banks: US rules still allow them with approval; many airlines do not.
- Families: ICAO's cap is per person, so count banks per traveler, not per bag.
How to calculate watt-hours
Limits are set in watt-hours (Wh), not milliamp-hours (mAh). IATA's passenger guidance on lithium batteries (31 March 2026) says Wh is the rated capacity in amp-hours multiplied by the nominal voltage, and that lithium-ion batteries are required to have the Wh rating marked on the case.
Wh = mAh x V / 1,000
mAh = capacity printed on the bank
V = nominal voltage printed on the label
1,000 converts milliamp-hours to amp-hours
Use the nominal voltage on the label, not the 5 V a USB port delivers: at 5 V a 20,000 mAh bank computes to 100 Wh, against 74 Wh at 3.7 V. Where the case prints Wh, use that.
Illustrative example, assuming 3.7 V (and 3.6 V):
| Bank label | Wh at 3.7 V | Wh at 3.6 V | Against the 100 Wh line |
|---|---|---|---|
| 10,000 mAh | 37.00 | 36.00 | Well under |
| 20,000 mAh | 74.00 | 72.00 | Under |
| 26,800 mAh | 99.16 | 96.48 | Under by 0.84 Wh at 3.7 V |
At 3.7 V the break-even point is 100 / 3.7 x 1,000, or about 27,027 mAh. A 30,000 mAh bank computes to 111 Wh, inside the 101-160 Wh band; 160 Wh corresponds to about 43,243 mAh. The margin is thin: if the same 26,800 mAh bank's label gave 3.8 V, it would compute to 101.84 Wh.
What US rules require
The FAA's PackSafe page on lithium batteries (last updated 11 August 2026) says spare lithium-ion and lithium metal batteries, including power banks, must be carried in carry-on baggage only, with terminals protected from short circuit. Lithium-ion batteries are limited to 100 Wh each; with airline approval a passenger may carry up to two spare batteries of 101-160 Wh. Batteries must be for personal use, and the page warns that many airlines set stricter limits.
The regulation is 49 CFR 175.10(a)(18). Each spare must meet the UN 38.3 tests and be individually protected against short circuits, and paragraph (a)(18)(iv) treats any article whose primary purpose is to power another device as a spare battery, which covers power banks. In the eCFR text up to date as of 16 October 2026, the section sets no cap on the number of batteries of 100 Wh or less and does not ban use in flight.
The global rules changed in 2026
ICAO said its new power bank specifications would limit passengers to two power banks each and prohibit recharging them during flights, effective 27 March 2026.
IATA's guidance document for operators (dated 31 March 2026) sets out the addendum's passenger terms. Power banks must be carry-on, must not be recharged on board (new requirement), should not be used to recharge another device on board (a recommendation, not a ban), are limited to two per person, and must be protected against short circuits. The addendum separates power banks from spare batteries for the first time, and airlines may require approval, extra separation or a charge under 25% for many batteries.
The same document says enforceability depends on each country's adoption process, immediate in some and slower where legislation is needed. So the US federal text can still have no count cap while many airlines already apply ICAO's terms or stricter ones.
How the 100-160 Wh band is changing
The draft addendum text in the IATA document still allows 100-160 Wh batteries, two spares at most, with operator approval. IATA says this allowance for 100-160 Wh power banks will not carry into the 68th edition of its Dangerous Goods Regulations, in force from 1 January 2027. Its passenger table already marks power banks above 100 Wh "Forbidden," while 100-160 Wh spare batteries for cameras or laptops stay allowed with approval. In the US, 49 CFR still allows up to two 101-160 Wh spares, power banks included, with airline approval. Singapore Airlines and Asiana still accept 100-160 Wh banks with approval; Southwest caps banks at 100 Wh, Emirates keeps them under 100 Wh, and Delta allows 100 Wh each "with no exceptions."
Where airlines go further
Each entry comes from the airline's own page, opened on 20 October 2026.
| Airline | Date given | Count and capacity | Use and storage |
|---|---|---|---|
| Southwest | One-bank limit effective 20 April 2026 | One power bank, 100 Wh maximum | Not in the overhead bin; in a personal item under the seat. No charging from in-seat power. In use, it must be visible, not in a bag. |
| Delta | No date shown on page | Up to two, 100 Wh each, "with no exceptions" | No overhead bin. Not recharged on board, and not used to recharge a device during taxi, take-off and landing. |
| Emirates | Release of 30 September 2025; effective 1 October 2025 | One power bank under 100 Wh; capacity rating information must be available | No use: neither charging devices from it nor charging it from aircraft power. Seat pocket or bag under the seat, not overhead. |
| Singapore Airlines | Posted 6 April 2026; effective 15 April 2026 | Up to two; 100 Wh or less needs no approval, 100-160 Wh needs prior approval, above 160 Wh not allowed | Seat pocket or under the seat, not overhead. No charging from seat outlets or USB ports, and no charging personal devices from the bank in flight. |
| Asiana | No date shown on page | Up to two at 100 Wh or less; 100-160 Wh with approval (two in total); above 160 Wh prohibited | No use or charging on board. Not in the overhead bin. Terminals taped or each bank in its own bag. A bank may be refused if its capacity is not shown. |
On 23 January 2026, Korean Air announced that Korean Air, Asiana, Jin Air, Air Busan and Air Seoul would ban all in-flight use of power banks from 26 January 2026 on domestic and international flights; banks stay on the passenger, in the seat pocket or under the seat, never overhead.
This table does not cover American, United, Lufthansa Group or Chinese carriers; check their own pages before you fly.
Gate-checked bags and the hold
The FAA says that when a carry-on bag is checked at the gate or at planeside, all spare lithium batteries and power banks must be removed from the bag and kept with the passenger in the cabin.
The TSA prohibits power banks in checked luggage, which covers any bag that goes in the hold, whether checked at the counter, the curb or the gate.
The FAA keeps a chart of lithium battery incidents involving smoke, fire or extreme heat, which it says is not a complete listing.
Frequently asked questions
Can I fly with a bank that shows only mAh?
IATA's passenger guidance says an airline may refuse a battery if staff cannot verify its Wh rating from the battery or its documentation, and Asiana's page says a bank may be refused if its capacity is not shown. Emirates requires capacity rating information on every bank. Keep the box or a photo of the spec sheet.
What counts as a power bank rather than a spare battery?
IATA describes a power bank as a universal external power source for devices such as phones, and a spare battery as one designed to fit a specific device. US rules make no such split and carry both as spares. The difference matters for the two-bank cap and the 100-160 Wh band.
How do I protect the terminals?
The FAA lists leaving batteries in retail packaging, taping over exposed terminals, using a battery case or sleeve, or placing each snugly in a plastic bag or protective pouch. Korean Air says the Hanjin group carriers provide insulating tape at check-in, the gate and on board.
Can I bring a damaged or recalled power bank?
The FAA says damaged or recalled batteries likely to create sparks or dangerous heat must not be carried in carry-on or checked baggage unless the battery has been removed or made safe. For recalls, it points to the Consumer Product Safety Commission, the maker or the seller.
Will TSA stop me at the checkpoint for a power bank?
The TSA's power bank page (last updated 14 May 2025) allows power banks in carry-on bags only, with the final decision resting with the officer. Count, storage and use limits are the airline's own, so a bank that clears security can still be refused at check-in or the gate.
Before you pack: a checklist
- Find the Wh rating on each bank; if only mAh is printed, multiply by the label's nominal voltage and divide by 1,000.
- Take no more banks than the airline allows: one on Southwest and Emirates, two on Delta, Singapore Airlines and Asiana.
- Tape the terminals or put each bank in its own pouch or bag.
- Keep banks within reach, never in checked luggage; all the airlines in the table also bar the overhead bin.
- If a bag may be gate-checked, take the banks and spare batteries out before you board.
Check the airline's page a few days before departure for count, Wh ceiling, storage and use: Emirates, Korean Air, Singapore Airlines and Southwest have all changed their rules since October 2025.
Sources
- FAA PackSafe: Lithium Batteries (last updated 11 August 2026)
- FAA Lithium Battery Incidents (last updated 11 August 2026)
- 49 CFR 175.10, eCFR (up to date as of 16 October 2026)
- TSA: Power Banks (last updated 14 May 2025)
- ICAO: New power bank restrictions will safeguard international aviation (27 March 2026)
- IATA: Changes Regarding Power Banks, guidance for operators (31 March 2026)
- IATA: Passengers Travelling with Lithium Batteries (31 March 2026)
- Southwest Airlines: Lithium batteries
- Delta: Battery or Fuel-Powered Items
- Emirates: power bank rules in full effect (30 September 2025)
- Singapore Airlines: Advisory on the carriage of power banks (6 April 2026)
- Asiana Airlines: Restricted items
- Korean Air newsroom, 23 January 2026 (in Korean)
