Power banks for travel: airline rules, real capacity, and five worth carrying

What airlines allow as of late 2026

The global baseline changed in March 2026. The International Civil Aviation Organization (ICAO), the UN body whose standards apply across its 193 member states, adopted rules effective 27 March 2026. AirlineRatings reports that they cap passengers at two power banks in the cabin and ban recharging them during the flight. Hong Kong's Civil Aviation Department applied the same two-bank cap and charging ban to all departures from Hong Kong International Airport the next day.

The watt-hour (Wh) thresholds work as before. Under 100Wh needs no special permission. Between 100 and 160Wh you need the airline's approval in advance. Anything over 160Wh is not allowed on passenger aircraft at all. Power banks cannot go in checked baggage under any circumstances. AirlineRatings also notes they cannot be stowed in overhead bins, so crew can see and reach one if it overheats.

Individual airlines can be stricter. GV Wire reported that from 20 April 2026 Southwest Airlines allows one power bank per passenger, bans them from overhead bins and no longer lets them be recharged from in-seat power. The same report cites FAA figures of 97 battery incidents involving smoke, fire or extreme heat on flights in 2025, up from 89 in 2024. Check the operating carrier's own rules before each trip, especially on codeshare flights.

• Two power banks at most on most international flights; one on Southwest

• Carry-on only, never in checked bags

• Keep it under the seat in front of you or on your person, not in the overhead bin

• Under 100Wh: no approval needed. 100–160Wh: get airline approval first. Over 160Wh: not allowed

• No recharging the power bank itself during the flight

Why 10,000mAh doesn't mean 10,000mAh at your phone

The mAh number on the box describes the internal cells, which run at about 3.6V. USB delivers 5V or more. A hobbyist bench test published on splitbrain.org explains that the voltage conversion costs energy, so usable output is always below the cell total. With a 15W load, an Anker 20,000mAh bank rated at 72Wh delivered 64.7Wh (about 90%). A Baseus 26,800mAh bank rated at 99.2Wh delivered 90.3Wh. A third bank sold as 25,000mAh and 90Wh delivered only 72.4Wh, and its own fine print admitted about 80Wh after losses.

The phone then loses more energy while charging its own battery. Engadget charged phones, tablets and laptops from nearly empty and found that, averaged across the banks it tested, about 60% of the rated capacity reached the device. That came to roughly 5,800mAh from a 10,000mAh bank, 11,250mAh from a 20,000mAh bank and 16,200mAh from a 25,000mAh bank. In practice, plan on one and a half to two phone charges from a 10,000mAh bank and about three from a 20,000mAh one.

For airline purposes, the Wh figure printed on the case is the one that counts. If the label only gives mAh, multiply by 3.6 (the cell voltage) and divide by 1,000. By that sum, a 25,000mAh bank comes to 90Wh, which is under the 100Wh line.

Pocket size: two 10,000mAh options

Anker Nano Power Bank (10K, 45W). Who it suits: phone users who want a single item with the cable attached. It has a built-in retractable USB-C cable and a display that shows charge status. In Macworld's October 2025 review, it charged an iPhone 15 by 52% in 30 minutes, had enough capacity for two full iPhone 15 charges, and took about 2 hours 15 minutes to recharge itself at up to 30W. The 45W maximum applies to Samsung phones; Anker says iPhones top out at 40W. It measures 3.2 x 2 x 1.4 inches, and Macworld listed it at $59.99. Main trade-off: power drops sharply when you share it. With two devices plugged in, Macworld lists up to 15W on the cable and 7.5W on the second port; with three, 7.5W each. The reviewers also mentioned a housing that scratches easily and no magnetic mount.

Anker MagGo Power Bank (10K). Who it suits: iPhone owners who want to snap a charger on and keep using the phone, for example in a queue or on a layover. It charges wirelessly over Qi2 at 15W. Engadget measured about 1.64 iPhone 15 charges, a 4-to-100% charge in 2 hours 26 minutes, and a weight of 8.82 oz. Macworld got one full iPhone 15 charge plus another 70%, and found its 27W USB-C port added 35% to an 11-inch iPad Pro. Main trade-off: you get fewer phone charges than from a wired 10,000mAh bank. Anker's own 10K Fusion managed about 1.86 iPhone 15 charges in Engadget's tests, and both Engadget and Macworld called the MagGo's price high.

Long travel days: two 20,000mAh options

Belkin BoostCharge Power Bank 20K with Integrated Cable. Who it suits: travelers who want several phone top-ups for little money. Engadget measured 3 to 3.5 iPhone 15 charges and 2.5 to 3 charges of a Galaxy S23 Ultra. It weighs 14 oz, peaks at 30W, and cost around $50 when Engadget updated its guide in February 2026. Main trade-off: Engadget found it charges devices more slowly than the other banks it tried.

Nimble Champ Pro. Who it suits: people carrying a tablet, or two USB-C devices that need charging at once. It shares 65W across two USB-C ports and weighs 12.9 oz. Engadget measured about 2.95 charges of an iPhone 11, 2.99 of a Galaxy S22 Ultra and 1.83 of an iPad Air. Engadget listed it at around $100 in February 2026. Main trade-off: it costs about twice as much as the Belkin, and Engadget found its indicator lights underestimate the remaining charge.

For a laptop: Anker Laptop Power Bank (25K, 165W)

Who it suits: people who work on a laptop in transit, or who want one bank for a whole family's devices. It has three USB-C outputs (two built-in cables and one port) at up to 100W each, plus a USB-A port, with a combined limit of 165W. One cable retracts and is 2.3 ft long. The other is a short loop that doubles as a carry strap. Gizmodo notes the 25,000mAh battery stays within the 100Wh carry-on limit. Gizmodo also reported a $134 list price and a $95 Prime Big Deal Days price in October 2026. No wall charger comes in the box, and Anker says fast recharging needs one rated at 100W or more.

Engadget measured 4 to 5 iPhone 15 charges, 1.75 to 2 iPad Air charges and 0.68 of a MacBook Pro charge. Main trade-off: it weighs 1.31 lbs and gives you about two-thirds of a MacBook Pro charge, not a full one. On an airline with a one-bank limit, such as Southwest, it would also be the only bank you can bring.

How to choose and pack

Start from the 60% figure and work back from your devices. Someone with only a phone on a day trip rarely needs more than 10,000mAh. A phone plus a tablet over a long connection fits the 20,000mAh class. Only laptop users need a 25,000mAh, 100W-class bank, and that one sits close to the 100Wh limit.

• Find the Wh rating on the case before you leave; staff may check it

• Charge the bank fully at home or at the airport, since recharging in flight is now banned on most international routes

• Count your banks against the strictest airline on your itinerary

• Keep the bank in your under-seat bag, where you can see it and reach it quickly

• Bring the right wall charger for the bank's input speed, so it recharges overnight at your hotel

Sources

• New airline power bank rules: what passengers need to know (AirlineRatings)
• Southwest Airlines to limit passengers to one portable charger on flights (GV Wire)
• Hong Kong Civil Aviation Department press release on power banks, 28 March 2026
• The best power banks and portable chargers for every device in 2026 (Engadget)
• Anker Nano 10K Power Bank 45W review (Macworld)
• Anker MagGo Power Bank 10K review (Macworld)
• Anker's 165W 25,000mAh laptop power bank deal (Gizmodo)
• 65W power bank comparison (splitbrain.org)