Power Banks in Carry-On: Airline Rules, Watt-Hour Limits and the Capacity Calculator

The International Civil Aviation Organization published an addendum to its dangerous-goods instructions on 27 March 2026, and it took effect the same day. The text is Addendum No. 1 to Doc 9284-AN/905, reproduced in full as Appendix C of IATA's guidance document for operators dated 31 March 2026.

IATA summarises the addendum in three bullets, verbatim: it will "separate out power banks from spare batteries", "limit passengers (and crew) to two power banks for personal use", and "prohibit passengers recharging the power bank in flight".

One word in that text carries an unusual amount of weight, and it is routinely flattened in consumer coverage. The amended Table 8-1 distinguishes must not from should not:

So the only binding restriction on use is that you may not top the power bank itself up. Charging your phone from it is, at the global level, advice — and that is exactly the gap the stricter airline policies moved into.

The addendum also names a figure that matters to frequent flyers: power banks an airline supplies to its own crew for operational duties must not exceed 100 Wh, with no upward exception at all.

A model like the INIU Powerbank 10000mAh 22.5W Kompakt shows how small that can be in practice: at roughly 36 to 37 Wh it sits far below every limit named here, and it is easy enough to protect individually the way the rule requires.

The important point first: the worldwide rule arrived after the airline rules, not before. Knowing the order explains why older articles and current airline pages disagree.

The number 20 is not invented. IATA's passenger table of 31 March 2026 still carries footnote 2: "Each person is limited to a maximum of 20 spare batteries of any type" — for spare batteries. Footnote 3 immediately below reads "Limited to a maximum of 2 power banks". That split is the new part. Before it, power banks fell under the first footnote, which is why Stiftung Warentest was right to report on 22 January 2026 that Lufthansa's two-unit rule went beyond the industry baseline of the time. Since late March 2026 the two-unit rule is the worldwide standard, which is why Germany's ADAC states it on 14 July 2026 without any such distinction: "Maximal sind zwei Powerbanks im Handgepäck erlaubt." Both statements are correct; they describe different moments.

A unit like the Anker Nano Powerbank, 10.000mAh Externer Akku mit 70cm Anker InstaCord Einzugskabel, 45W Max Kompakter Akku, Smart-Display stayed unproblematic through all three tightenings: at roughly 36 to 37 Wh it sat far below every limit in force, whether the rule of the day allowed 20 spare batteries or only two power banks.

Between 100 Wh and 160 Wh things get awkward — inside a single document. IATA's 31 March 2026 guidance carries two statements that do not agree:

The Luftfahrt-Bundesamt sides with the legal text, while stating on the same page that "Lose Lithiumersatzbatterien (power banks) sind im aufgegebenen Gepäck verboten" — loose spare lithium batteries and power banks are forbidden in checked baggage. That page carries no last-updated date, which for a regulator's page on this topic is a real gap.

What to do with that in practice: if your power bank is above 100 Wh, the answer is not "it's fine with approval". The answer is that the airline decides, the operational industry table says forbidden, and you want that approval in writing before you leave for the airport. For almost everyone the simpler route is to stay below 100 Wh – with a compact model like the Anker MagGo Powerbank 10.000 mAh Qi2 15 W mit Halterung, for instance.

The formula is trivial:

Wh = (V × mAh) ÷ 1000

At the usual nominal lithium-ion cell voltage of 3.7 V, the 100 Wh ceiling works out at roughly 27,027 mAh. That is the number in nearly every guide, and as a rule of thumb it is fine.

The trap: plenty of cells are rated 3.6 V, not 3.7 V. That moves the ceiling to roughly 27,778 mAh. A 27,650 mAh device therefore sits either under or over the line depending on its cell chemistry — and such a device is genuinely on sale (see the table below).

Hence the rule that matters: the Wh figure printed on the casing beats any arithmetic you do yourself. The manufacturer knows its cell voltage; you do not. The conversion is for sizing up a purchase, not for arguing at the gate. For a fuller treatment of the various numbers printed on a power bank, see converting mAh to Wh.

A real-world example of the 20,000 mAh row is the Anker Powerbank, 20.000mAh tragbares Ladegerät mit integriertem USB-C-Kabel, 87W Max Schnellladung, kompatibel mit MacBook, iPhone, Samsung und mehr: it works out to roughly 72 to 74 Wh, comfortably inside the free-to-carry range.

All figures taken from the retail listings on amazon.de, retrieved on 3 August 2026. Prices move; the watt-hour figure is what matters here.

Two things stand out.

First, the Anker Prime Powerbank 27.650 mAh (250 W) — the Anker Prime. At 27,650 mAh it sits above the 27,027 mAh rule of thumb — yet the product page explicitly states "99,54Wh" and advertises it as the maximum capacity still permitted on an aircraft, under 100 Wh. That is the 3.6 V effect from the section above. Anyone calculating at 3.7 V alone will wrongly write off a perfectly legal device.

Second, the blanks. Of these six listings, only two state a watt-hour figure at all as of 3 August 2026. On the other four, the one number aviation actually cares about appears nowhere in the offer — at best it is on the casing, which you get to read after buying. Below 20,000 mAh this hardly matters, because the margin to the limit is enormous. From 25,000 mAh upwards it is the point at which you should ask before you pay.

For the separate question of 100 W USB-C laptop charging and how close to the 100 Wh line it is sensible to go, there is a dedicated article: power banks for laptops.

Here is the real obstacle with this topic: most airlines put their dangerous-goods pages behind bot protection that blocks automated retrieval. All 13 pages below were requested on 3 August 2026; ten of them answered with HTTP 403 or 404. Rather than filling the gaps with someone else's summary, they are recorded as what they are — with the link you can check yourself.

For every row marked "not stated", the worldwide minimum in the first row applies: any airline may be stricter, none may be more permissive. If you are flying one of the lower carriers with more than one power bank, or with a device close to 100 Wh, a short enquiry before departure is the only answer you can rely on. That is exactly what ADAC recommends on 14 July 2026.

Anyone limited to a single unit, as with Emirates, is well served by a higher-capacity model like the Anker Laptop Powerbank 25.000 mAh, 165 W, rated at roughly 90 Wh – plenty of reserve without touching the 100 Wh line.

Three things changed in January 2026 that you notice at your seat.

Recharging the power bank from aircraft power is prohibited everywhere. This is the one binding change ICAO made, and it covers the USB sockets in the seat as well as any AC outlet.

Charging your phone from the power bank depends on the airline. Globally it is a recommendation to refrain. In the Lufthansa Group it has been forbidden since 15 January 2026 — German trade title fvw reported on 14 January 2026 that power banks "dürfen während des Flugs generell nicht mehr genutzt und auch nicht geladen werden". ADAC puts it plainly on 14 July 2026: "Die Nutzung der Akkus während eines Fluges ist komplett verboten."

Not in the overhead bin. ADAC states: "Sie müssen in Reichweite aufbewahrt werden und dürfen nicht ins Gepäckfach." The reason is not bureaucratic. A fire in the seat pocket or in the bag under the seat in front is reachable by crew in seconds; a fire in a closed bin above your head is not. Emirates has required the same since 1 October 2025.

There is also the short-circuit rule, which predates all of this and which the new ICAO text repeats explicitly: every power bank must be individually protected — original packaging, taped-over terminals, or a separate pouch each. Two power banks rattling loose in the same camera-bag pocket do not meet that.

There is no gradation here and no exception. ICAO's text for power banks is "must be carried as carry-on baggage". Germany's Luftfahrt-Bundesamt states that loose spare lithium batteries and power banks are forbidden in checked baggage. ADAC writes: "Im aufgegebenen Gepäck bleiben die Powerbanks weiterhin generell verboten." Three sources, one answer.

The practical case that catches people is the cabin bag surrendered at the gate because the overhead bins are full: the power bank has to come out first. That is the single most common route by which a power bank ends up in the hold.

Security screening mainly checks that the power bank is in your carry-on — the scanner shows that. Watt-hours usually only come up when a device is conspicuously large or an officer picks it up. This is precisely why a printed Wh figure is so valuable: it ends the conversation without anyone having to calculate.

What draws attention: devices well above 20,000 mAh, devices with no legible marking at all, and more than two power banks per person. Emirates has explicitly required since 1 October 2025 that the capacity rating be clearly visible on the device — a worn or covered label is a foreseeable problem there.

Two units, under 100 Wh, carry-on only, not in the overhead bin, never recharged from aircraft power. Follow that and you are fine with any airline in the world, because an airline may be stricter than the worldwide minimum but none is stricter than "two units under 100 Wh, don't use them". A device with a printed watt-hour figure below 100 Wh is the cheapest insurance against any discussion there is.

One date is worth noting: 1 January 2027. The 68th edition of the IATA Dangerous Goods Regulations takes effect, and the current guidance expressly applies "not beyond 31 December 2026". If you own a power bank in the 100–160 Wh band, keep that date in view.