Can I bring a power bank on a plane? Yes, but only in your carry-on bag, never in checked luggage. Most power banks rated 100 Wh or less need no special permission, while larger ones need airline approval or are banned. Several airlines have also tightened rules on using power banks in flight. This guide is based on the published rules as of 11 November 2026.
The basic rules for US and UK flights
The TSA says portable chargers and power banks containing a lithium-ion battery must be packed in carry-on bags. It also says spare lithium batteries, including power banks and phone chargers, are not allowed in checked luggage. The TSA page leaves the final call to the officer at the checkpoint.
The UK Civil Aviation Authority (CAA) says the same: power banks must always stay in the cabin. The CAA also sets the size limits shown below. A summary of US airline policies published in July 2026 lists the same 100 Wh and 160 Wh thresholds for carriers such as Delta, United, American and Alaska.
| Battery rating | Carry-on | Checked bag |
|---|---|---|
| 100 Wh or less | Allowed, no approval needed | Not allowed |
| Over 100 Wh, up to 160 Wh | Airline approval required | Not allowed |
| Over 160 Wh | Not allowed in passenger baggage (CAA) | Not allowed |
Airlines can be stricter than the baseline. Delta and Allegiant, for example, are listed with a maximum of 20 spare batteries, while American is listed with four spares under 100 Wh. In the UK, the CAA rule (effective 27 March 2026) allows a maximum of two power banks per person, and each must be protected from short circuits when not in use. Protect terminals with the original packaging, a case or tape.
How to work out watt-hours from mAh
Many power banks print only milliamp-hours (mAh). The CAA gives the formula: multiply volts by mAh, then divide by 1,000. So Wh = mAh × V ÷ 1,000. Use the voltage printed on the label. The examples below assume 3.7 V, a common figure for the battery cells inside, but your label may differ.
| Capacity (mAh) | Calculation at 3.7 V | Watt-hours | Status |
|---|---|---|---|
| 5,000 | 5,000 × 3.7 ÷ 1,000 | 18.5 Wh | Fine |
| 10,000 | 10,000 × 3.7 ÷ 1,000 | 37 Wh | Fine |
| 20,000 | 20,000 × 3.7 ÷ 1,000 | 74 Wh | Fine |
| 26,800 | 26,800 × 3.7 ÷ 1,000 | 99.2 Wh | Just under 100 Wh |
| 30,000 | 30,000 × 3.7 ÷ 1,000 | 111 Wh | Needs airline approval |
| 50,000 | 50,000 × 3.7 ÷ 1,000 | 185 Wh | Over 160 Wh: not allowed |
If the label shows neither Wh nor a clear mAh and voltage, a security officer may not be able to confirm the rating. Choose a model with the Wh figure printed on it.
New limits on using power banks in flight
Packing the battery correctly is only half the story. Some airlines now restrict how you use it on board. These are the changes confirmed from pages read for this guide:
| Airline or regulator | Rule | Effective |
|---|---|---|
| Southwest | Power banks can’t be used while stored in a bag or overhead bin; keep them in plain view | 28 May 2025 |
| Emirates | One power bank under 100 Wh per passenger; no using it to charge devices on board; no recharging it from aircraft power; store in seat pocket or under-seat bag | 1 October 2025 |
| UK CAA | Don’t recharge power banks on board or use them to charge other devices | 27 March 2026 |
| Southwest | One portable charger per passenger; none in overhead bins; no recharging from in-seat power | 20 April 2026 |
The CAA’s consumer page adds practical advice: keep your power bank easy to reach, and expect to be asked to keep it in the seat pocket rather than the overhead locker. If it overheats or smokes, stop using it and alert the crew. Southwest’s April 2026 limit was reported by Reuters, which tied it to a global standard from the UN aviation agency ICAO.
Other US airlines may have no separate published rule on use, but crew can always ask you to stop. Policies change, so check your airline’s page shortly before you fly.
How to choose a flight-friendly power bank
- Look for a printed Wh rating. It saves you doing the maths at the checkpoint and answers any question at the gate.
- Stay under 100 Wh. That is roughly 27,000 mAh at 3.7 V, and it avoids approval and quantity hassles.
- Pick one good unit, not several. Emirates and Southwest now allow one, and the UK allows two.
- Choose USB-C output. USB-C with Power Delivery can charge phones, tablets and many laptops with one cable, so you carry fewer cables.
- Check for safety markings and a known brand. Look for test and certification marks on the label, and avoid unbranded units with no ratings at all.
- Retire damaged units. The CAA says not to carry a battery that is damaged, swollen or overheating.
What to do now
- Find the Wh rating, or calculate it from mAh and volts.
- Put the power bank in your carry-on or personal item, never your checked bag. Take it out of any bag you may have to gate-check.
- Charge your phone and the power bank before you leave home.
- Check your airline’s policy for in-flight use, especially Southwest, Emirates or any airline you fly rarely.
- Check your bag size too: see our US carry-on size guide. Our guide to choosing a portable car jump starter covers flying with larger batteries, and our luggage tracker comparison helps if you want to track your checked bag.
FAQ
Can I put a power bank in my checked bag?
No. The TSA and the UK CAA both say power banks belong in the cabin only.
Is a 20,000 mAh power bank allowed on a plane?
Generally yes. At 3.7 V it works out to 74 Wh, under the 100 Wh limit. Check the actual voltage on your label, and your airline’s quantity and in-flight use rules.
Can I charge my phone from a power bank during the flight?
It depends on the airline. Southwest allows use in plain view (check its newer one-charger rule), Emirates bans it, and the UK CAA says power banks should not be used to charge other devices on the aircraft. Check before you fly.
Bottom line
Carry one clearly labelled power bank of 100 Wh or less in your cabin bag, and you will meet the baseline rules for US and UK flights. The bigger change is in the air: several airlines now limit how many you can bring and whether you can use them. Confirm your airline’s current rules before you travel.
Sources
- TSA: Power Banks
- UK CAA: Pack Right
- UK CAA: Changes to rules on lithium batteries and power banks
- Your Mileage May Vary: Power bank rules for every US airline
- View from the Wing: Southwest power bank rule
- GV Wire (Reuters): Southwest one portable charger limit
- Aviation Business News: Emirates power bank rules
