Power banks on planes: the 100 Wh decision guide
Aviation security limits portable battery packs by watt-hours (Wh), not milliamp-hours (mAh). Here is the 30-second label test, the full conversion formula, the 5V calculation trap, and the 2026 airline policies governing carry-on battery packs.
On this page · 11 sections
1. The Verdict: Wh, Not mAh
The limit is watt-hours, not milliamp-hours. Under 100 Wh: carry-on, no approval needed. 100–160 Wh: airline approval, max two spares. Over 160 Wh: it doesn't fly. Never in checked baggage — ever. And since 2026, many airlines cap you at two banks and keep them out of the overhead bin. Here is the label test, the conversion table, and the current airline rules, verified 24 Aug 2026.
Every commercial aviation authority on earth regulates portable external chargers, backup batteries, and power banks based on their total electrical energy capacity measured in watt-hours (Wh). However, consumer electronics manufacturers market these devices almost exclusively by their electric charge rating in milliamp-hours (mAh).
This disconnect causes widespread confusion at airport checkpoints. Travelers holding a 20,000 mAh or 27,000 mAh pack often wonder if their charger exceeds federal thresholds. In reality, the calculation is straightforward once you know which voltage to apply and where to look on your device's regulatory label.
2. The Rule: The Three Watt-Hour Bands
Under international civil aviation standards and United States federal regulations (49 CFR § 175.10), spare lithium-ion batteries and power banks are divided into three distinct regulatory tiers based on their energy content:
Standard Carry-On
Allowed in carry-on baggage in reasonable quantities for personal use. No prior airline approval is required under federal rules (though individual carrier quantity caps apply in 2026).
Restricted Approval
Requires explicit advance approval from the airline. Passengers are legally limited to a maximum of two spare batteries in this capacity band, carried exclusively in the cabin.
Strictly Prohibited
Power banks and spare lithium batteries rated over 160 Wh are completely prohibited on passenger aircraft in both carry-on baggage and checked luggage under all circumstances.
Critical Safety Directive: Never in Checked Baggage — Ever
All portable power banks and spare lithium-ion batteries must travel in your carry-on luggage or on your person. They are strictly prohibited in checked hold baggage. In the rare event of a short circuit or thermal runaway, cabin crew are equipped with specialized containment bags and fire suppression equipment to manage lithium battery incidents; automatic cargo hold halon systems cannot reliably extinguish lithium battery thermal runaways.
The regulatory framework focuses strictly on cell energy content rather than physical dimensions because energy capacity directly dictates the heat output and severity of potential thermal events.
3. Read the Label: The 30-Second Test & 5V Trap
Before calculating anything, look directly at the fine print printed on your power bank's exterior casing. Under international manufacturing standards, reputable brands print the rated capacity in watt-hours on the back or bottom panel (for example: "Rated Capacity: 74.0 Wh").
If your power bank only displays its capacity in milliamp-hours (mAh), you can calculate the watt-hour rating using the official conversion equation:
Where 3.7V represents the nominal internal operating voltage of standard single-cell lithium-ion chemistry.
The 5V Output Voltage Calculation Trap
The most common mistake travelers make is using the USB port output voltage (5V, 9V, 12V, or 20V USB-C Power Delivery) instead of the internal cell's nominal voltage (3.7V).
- The Erroneous 5V Calculation: A 20,000 mAh battery calculated at 5V output appears to be 100 Wh (
20,000 × 5 ÷ 1,000 = 100 Wh), making it look like it sits right at the regulatory limit. - The Correct 3.7V Cell Calculation: Calculated using the internal cell's true 3.7V nominal voltage, that exact same 20,000 mAh battery contains 74 Wh (
20,000 × 3.7 ÷ 1,000 = 74 Wh) — comfortably below the 100 Wh threshold.
At airport security checkpoints, Transportation Security Officers (TSOs) and international screeners inspect the printed Wh rating on the casing, not marketing claims or packaging. If your battery pack's label is completely worn off, scratched, or illegible, security personnel have the authority to confiscate or reject the device because compliance cannot be verified.
4. The Conversion Table: Know Your Number
To instantly determine whether your specific battery pack is allowed in carry-on luggage, refer to this reference conversion matrix based on standard 3.7V lithium-ion cell chemistry:
| Marketed Capacity (mAh) | True Energy Rating (Wh @ 3.7V) | Carry-On Status | Airline Approval Needed? | Typical Device Example |
|---|---|---|---|---|
| 5,000 mAh | 18.5 Wh | Permitted (Carry-On) | No | Ultra-slim pocket charger (1 phone charge) |
| 10,000 mAh | 37.0 Wh | Permitted (Carry-On) | No | Standard compact travel battery (2 charges) |
| 15,000 mAh | 55.5 Wh | Permitted (Carry-On) | No | Mid-sized dual-port power bank |
| 20,000 mAh | 74.0 Wh | Permitted (Carry-On) | No | Popular high-capacity pack (Anker, Baseus, etc.) |
| 26,800 mAh | 99.16 Wh (~99 Wh) | Permitted (Carry-On) | No | Industry-standard "flight-friendly maximum" |
| 27,000 mAh (1S Cell) | 99.9 Wh | Permitted (Carry-On) | No (at 3.7V) | Knife-edge threshold pack (read casing label) |
| 30,000 mAh | 111.0 Wh | Restricted (Max 2 Spares) | Yes (Airline Approval) | High-capacity laptop portable charger |
| 40,000 mAh | 148.0 Wh | Restricted (Max 2 Spares) | Yes (Airline Approval) | Multi-day expedition & heavy laptop bank |
| 50,000 mAh | 185.0 Wh | PROHIBITED | Cannot Fly | Portable generator / outdoor station |
Have a non-standard capacity or unique device? Use our interactive Watt-Hour Battery Calculator to enter your exact voltage and milliamp-hour values to instantly verify airline compliance.
5. The 27,000 mAh Knife-Edge & Dual-Cell Trap
The 27,000 mAh capacity is one of the most heavily searched specifications in aviation travel because it represents the mathematical razor's edge of the 100 Wh regulatory boundary:
At exactly 99.9 Wh, a standard single-cell nominal battery sits 0.1 Wh below the 100 Wh threshold, legally flying in carry-on luggage without requiring airline approval.
The Dual-Cell (2S) 7.4V Danger
However, travelers must be aware of the dual-cell series (2S) configuration. Several modern high-speed laptop chargers wire two lithium-ion cells in series to achieve higher output charging speeds, doubling the internal nominal voltage to 7.4V.
Because 199.8 Wh significantly exceeds the 160 Wh legal limit, a 27,000 mAh dual-cell pack is prohibited on passenger aircraft.
The Golden Rule: The printed Wh number on the physical casing is the only number that aviation authorities recognize. Never guess your pack's configuration from retail marketing descriptions—always verify the printed rating on the battery housing before heading to the airport.
6. The 2026 Airline Era: Two Banks, Under the Seat
While federal baseline rules establish the 100 Wh / 160 Wh limits, individual international carriers have enacted significantly stricter operational cabin restrictions throughout 2026 to mitigate lithium fire risks:
Lufthansa Group
Effective January 15, 2026Enforced across Lufthansa, SWISS, Austrian Airlines, Brussels Airlines, Eurowings, Edelweiss, Air Dolomiti, and ITA Airways:
- Quantity Cap: Strictly limited to a maximum of two power banks per passenger.
- In-Flight Prohibition: Zero in-flight use of portable chargers permitted; devices may not be plugged into power banks at any point during the flight.
- No Aircraft Recharging: Power banks may not be recharged using in-seat aircraft USB or 110V power outlets.
- Under-Seat Storage Only: Power banks must remain in your personal item under the seat in front of you and are prohibited from being stored in overhead baggage bins.
- 100–160 Wh Restrictions: Packs between 100–160 Wh require advance airline approval; packs above 160 Wh not allowed.
American Airlines
Effective May 1, 2026Under American Airlines' updated Restricted Items policies:
- Two Charger Limit: Passengers may carry up to two portable chargers, each rated under 100 Wh.
- Cabin Placement: Chargers must remain visible or within reach for the entire flight; overhead-bin storage is strictly prohibited.
- No Recharging Aboard: Power banks cannot be recharged using aircraft power supplies during transit.
- Total Spare Battery Allowance: Up to four spare lithium-ion batteries under 100 Wh plus two between 100–160 Wh permitted in carry-on. Power banks over 100 Wh are not permitted.
Emirates Airline
Enforced Since October 2025Emirates enforces a fleet-wide safety mandate prohibiting all in-flight usage and recharging of power banks aboard its aircraft.
The trend across global aviation is unmistakable: two-bank caps, under-seat storage, and strict overhead-bin prohibitions represent the emerging international baseline. Because individual carrier guidelines vary, always check your airline's specific baggage rules prior to departure.
7. Pack It Right: Checkpoint to Seat
Proper handling ensures your power banks clear security smoothly and remain safe throughout your flight:
Terminal & Short-Circuit Protection
Prevent metal objects (keys, coins, zippers) from contacting battery ports. Store power banks in individual protective sleeves, tape over exposed terminals, or keep them in dedicated organizer pouches.
Security Checkpoint Screening
At airports equipped with next-generation Computed Tomography (CT) scanners (see our CT scanner guide), power banks remain inside your carry-on bag. At conventional 2D X-ray lanes, remove large battery packs and place them in a separate screening bin.
When boarding the aircraft, always pack power banks in your smaller personal item (backpack, purse, or tote) that stows under the seat in front of you. Never leave portable chargers in rolling carry-on luggage placed in overhead bins.
8. What the Popular Sizes Actually Mean
Here is how the most common commercial battery capacities translate into real-world flight permissions:
- 10,000 mAh Packs (~37 Wh): Fully compliant worldwide. Standard pocket chargers from any major manufacturer fly without friction or special approvals.
- 20,000 mAh Packs (~74 Wh): Fully compliant. Popular travel power banks (such as most 20,000 mAh models from Anker and other leading brands) operate at approximately 74 Wh, safely below the 100 Wh ceiling.
- 26,800 mAh Packs (~99 Wh): The flight-friendly ceiling. Engineered specifically by electronics brands to max out allowable capacity while remaining under the 100 Wh threshold.
- 27,000 mAh Packs (~99.9 Wh): The knife-edge. Single-cell 3.7V configurations pass without approval; dual-cell 7.4V packs reach 199.8 Wh and are prohibited. Verify your casing label.
- 30,000 mAh Packs (~111 Wh): Requires airline approval. Because 30,000 mAh exceeds 100 Wh, you must contact your airline in advance and are restricted to a maximum of two spares.
Practical Rule of Thumb: Any power bank below 20,000 mAh is universally safe to fly. At 26,800 to 27,000 mAh, read the printed label. At 30,000 mAh and above, assume advance airline approval is required.
Related electronics guidelines: Learn more about packing power banks, laptops, drones, and electric toothbrushes in our dedicated Lithium Batteries & Electronics Hub.
9. Frequently Asked Questions
Is a 20,000 mAh power bank allowed on a plane?
Yes. At standard 3.7V nominal cell voltage, a 20,000 mAh power bank equals 74 watt-hours (Wh), well below the 100 Wh airline limit, and flies in carry-on baggage without airline approval.
What is 100 Wh in mAh for a power bank?
At the standard 3.7V nominal voltage of lithium-ion cells, 100 Wh equals approximately 27,027 mAh (commonly marketed as 26,800 mAh or 27,000 mAh).
Can I check a power bank in luggage?
No, never. Spare lithium-ion batteries and power banks are strictly prohibited in checked baggage worldwide due to cargo-hold fire risks and must travel in carry-on luggage.
How many power banks can I bring on a plane in 2026?
Under federal baseline rules, there is no set quantity limit for packs under 100 Wh, but major airlines in 2026 (including American Airlines and the Lufthansa Group) strictly cap passengers at two portable chargers per person.
Will a 27,000 mAh power bank fly on an airplane?
A single-cell 3.7V 27,000 mAh pack equals 99.9 Wh and flies without approval; however, dual-cell 7.4V packs equal 199.8 Wh and are completely prohibited. Always check the printed Wh rating on the label.
Can I bring a 30,000 mAh power bank on a flight?
A 30,000 mAh battery equals approximately 111 Wh at 3.7V nominal, placing it in the 100–160 Wh band which requires prior airline approval and is limited to a maximum of two spares.
Where do I find the watt-hour (Wh) rating on my power bank?
Look at the small printed regulatory text on the back or bottom of the pack for "Rated Capacity" or "Wh". If only mAh is shown, multiply mAh by 3.7 and divide by 1,000.
10. Key Takeaways & Distribution Kit
"The 2026 power-bank rule is Wh, not mAh: 20,000 mAh = 74 Wh — flies. 27,000 mAh = 99.9 Wh — just under. 30,000 mAh = 111 Wh — approval needed. Read the label."
Can you take a 27,000 mAh power bank on a plane? At 3.7V nominal it equals 99.9 Wh — just under the 100 Wh limit, so it flies without approval. But beware 7.4V dual-cell packs (199.8 Wh) which are completely banned. Always check the printed Wh rating on the casing: canicarryit.com/guides/is-your-power-bank-allowed-on-a-plane/
Aviation battery safety rules tightened significantly in 2026: Lufthansa Group (effective 15 Jan 2026) and American Airlines (effective 1 May 2026) both enforce a strict two-portable-charger limit per passenger with mandatory under-seat storage and a ban on overhead-bin placement or in-flight recharging. Full regulatory guide: canicarryit.com/guides/is-your-power-bank-allowed-on-a-plane/
Is your 20,000 mAh power bank allowed on a plane? Yes — at 3.7V nominal it is 74 Wh, well below the 100 Wh limit. Avoid the 5V trap (which falsely makes it look like 100 Wh). Remember: power banks must always be in carry-on luggage, never checked: canicarryit.com/guides/is-your-power-bank-allowed-on-a-plane/
11. Official Sources & Verification Ledger
This reference guide is maintained under CanICarryIt.com's strict primary-source verification policy. Every regulatory statement is mapped directly to our immutable fact ledger:
| Fact ID | Verified Regulatory Statement | Official Source & Authority | Verification Date |
|---|---|---|---|
| T11a | Wh conversion formula: Wh = (mAh × V) ÷ 1,000 using 3.7V nominal. 20,000 mAh = 74 Wh; 27,000 mAh = 99.9 Wh; 30,000 mAh = 111 Wh. Officers inspect printed Wh rating. 7.4V 2S packs reach 199.8 Wh (prohibited). | PowerBankZone / SortedGear Wh Calculator / Clutch Charger (2026) | 2026-08-24 |
| T11b | American Airlines (effective 1 May 2026): max two portable chargers ≤ 100 Wh each, carry-on only, under-seat/within reach, no overhead bins, no recharging aboard; spare batteries up to four < 100 Wh + two at 100–160 Wh. | American Airlines Restricted Items / CBS News / AeroXplorer (2026) | 2026-08-24 |
| T11c | Lufthansa Group (effective 15 Jan 2026): two power banks per passenger, no in-flight use, no recharging via aircraft outlets, no overhead bin storage; 100–160 Wh requires advance approval; > 160 Wh prohibited. | Lufthansa Group Passenger Safety Regulations / CineD (2026) | 2026-08-24 |
| U3 | Lithium battery baseline: < 100 Wh carry-on OK; 100–160 Wh airline approval, max 2 spares; > 160 Wh prohibited on passenger aircraft; never in checked baggage. | FAA 49 CFR § 175.10 / IATA Dangerous Goods Regulations | 2026-08-24 |
| K16 | Emirates Airline prohibited all in-flight usage and recharging of power banks fleet-wide effective October 2025. | Emirates Fleet Safety Directives (Oct 2025) | 2026-08-24 |