20000mAh Power Bank on a Plane? Wh & Airline Rules
Page updated · Sources and review method
At 3.7 V, 20,000 mAh is 74 Wh. That is within the common 100 Wh threshold, but airline and route conditions still apply.
The voltage matters.
These examples assume a 3.7 V nominal battery. Read your actual label: the same mAh at a different voltage gives a different Wh. USB charging output is not the nominal battery voltage.
This guide covers capacity, not certification, recalls or the condition of your particular product.
Power bank flight checker
Within the general 100 Wh capacity threshold. Select your airline to check its specific restrictions.
Why do 20,000 mAh labels show 72, 74 or 77 Wh?
The nominal voltage changes the calculation: 20,000 mAh at 3.6 V is 72 Wh, at 3.7 V is 74 Wh and at 3.85 V is 77 Wh. Do not replace a readable manufacturer Wh rating with a generic example. A 5 V USB output is a different specification and should not be paired with a nominal cell capacity.
Can I take two 20,000 mAh power banks?
Two 74 Wh devices each remain under 100 Wh, but there are still two devices. The listed Delta policy permits two, while Southwest and Emirates permit one. Read both the quantity and use restrictions for every airline on your trip; a connection does not combine those allowances.
Does a laptop-charging model have different rules?
A 65 W or 100 W output can describe a 20,000 mAh laptop-capable bank without changing its stored energy. It is Wh, not the maximum USB charging speed, that matters for the capacity check. This page does not estimate phone charges: actual usable energy depends on the device, conversion losses and charging conditions.
Last checked 2026-11-04
How that capacity compares by airline
Capacity guidance at 3.7 V. Open an airline’s page for quantity and onboard restrictions.
| Airline | Capacity result | Quantity |
|---|---|---|
| American Airlines | Carry-on only | 2 |
| United Airlines | Confirm with the airline | Confirm |
| Delta Air Lines | Carry-on only | 2 |
| Southwest Airlines | Carry-on only | 1 |
| Emirates | Carry-on only | 1 |
| Qatar Airways | Carry-on only | 2 |
| British Airways | Carry-on only | 2 |
| Lufthansa | Carry-on only | 2 |
| Korean Air | Carry-on only | 2 |
| Singapore Airlines | Carry-on only | 2 |
| Cathay Pacific | Confirm with the airline | 2 |
| ANA | Carry-on only | 2 |
| Japan Airlines | Carry-on only | 2 |
| AirAsia | Confirm with the airline | Confirm |
| Etihad Airways | Carry-on only | 1 |
Power bank flight FAQs
Quick answers before you pack.
Why do 20,000 mAh labels show 72, 74 or 77 Wh?
The nominal voltage changes the calculation: 20,000 mAh at 3.6 V is 72 Wh, at 3.7 V is 74 Wh and at 3.85 V is 77 Wh. Do not replace a readable manufacturer Wh rating with a generic example. A 5 V USB output is a different specification and should not be paired with a nominal cell capacity.
Can I take two 20,000 mAh power banks?
Two 74 Wh devices each remain under 100 Wh, but there are still two devices. The listed Delta policy permits two, while Southwest and Emirates permit one. Read both the quantity and use restrictions for every airline on your trip; a connection does not combine those allowances.
Does a laptop-charging model have different rules?
A 65 W or 100 W output can describe a 20,000 mAh laptop-capable bank without changing its stored energy. It is Wh, not the maximum USB charging speed, that matters for the capacity check. This page does not estimate phone charges: actual usable energy depends on the device, conversion losses and charging conditions.
How many Wh is 20,000 mAh?
At 3.7 V it is 74 Wh. Use the actual nominal battery voltage to calculate your device’s rating.
Can a 20,000 mAh power bank go in checked luggage?
No. Power banks must stay in the cabin regardless of capacity.