Most flights allow power banks up to 100 Wh in carry-on; 100–160 Wh need airline approval; bigger units aren’t allowed in baggage.
Airport rules can feel fuzzy, and battery labels don’t always help. This guide spells out the limits, the math behind capacity, and the packing steps that keep your charger cleared at security and in the cabin.
Power Bank Limits In Plain Numbers
The cap most travelers need to know is 100 watt-hours (Wh). A charger at or under 100 Wh can ride in your hand luggage without extra paperwork. Units between 101 and 160 Wh sit in a special lane: many carriers allow them, but only in the cabin and only with airline approval. Packs above 160 Wh are off-limits for passenger flights.
Those ranges are global norms shaped by aviation safety bodies. In the United States, the Federal Aviation Administration (FAA) and the Transportation Security Administration (TSA) publish matching guidance. Internationally, the International Air Transport Association (IATA) sets the common wording airlines follow.
Quick Capacity Reference (Common Sizes)
The table below converts popular milliamp-hour ratings to Wh using a 3.7 V nominal cell voltage, which fits most consumer packs.
| Label On Pack | Approx. Wh | Airline Status |
|---|---|---|
| 5,000 mAh | 18.5 Wh | Carry-on OK |
| 10,000 mAh | 37 Wh | Carry-on OK |
| 20,000 mAh | 74 Wh | Carry-on OK |
| 26,800 mAh | 99 Wh | Carry-on OK |
| 30,000 mAh | 111 Wh | Carry-on with airline approval (up to two spares) |
| 50,000 mAh | 185 Wh | Not permitted |
Carry-On Only, Not In Checked Bags
Portable chargers count as spare lithium batteries. That means cabin baggage only. Putting a battery pack in checked baggage raises fire risk in the hold, where crews can’t reach it fast. Place the pack where you can see it, and don’t wedge it under jackets or between seats while charging in flight.
Some airlines also ask that a power bank in use stays out of any bag during the flight so crew can monitor it. If a pack gets warm, unplug it and let it cool. If you spot smoke or a sweet, chemical smell, tell the crew right away.
How To Read Battery Labels (And Convert mAh To Wh)
Most packs print a Wh rating on the shell. If you only see milliamp-hours (mAh), you can convert with a simple formula: Wh = (mAh × V) ÷ 1000. For standard lithium-ion cells, V is 3.7. So a 20,000 mAh pack is 20,000 × 3.7 ÷ 1000 ≈ 74 Wh.
When a case lists more than one voltage (USB-C output at 5 V, 9 V, 12 V), ignore those. The Wh limit is based on the internal cell voltage, not the output. If the label shows a range, use the printed Wh value. If nothing is marked, treat the unit as over the limit until you can document the rating.
What About Power Stations And Large Packs?
Large banks sold for laptops or drones often sit near the 100 Wh line. Many makers ship a 99 Wh model to stay under the no-approval cap. Bigger bricks for camping or film gear often exceed 160 Wh and fall outside passenger rules. Shipping carriers have different rules; that’s a separate process from flying with a pack in your bag.
Approval Range: 101–160 Wh
If your pack is in this band, contact your airline early. Most carriers permit up to two spare batteries in this range per person when the agent adds a note to the reservation. Bring photos of the label showing Wh. Expect the gate agent to look for terminal protection and a power switch.
Approval doesn’t change the cabin-only rule. These packs stay out of checked bags. On board, keep them off the seat and away from heat sources like a sunlit window or a blanket-covered pocket.
Quantity Limits You Should Know
Small packs under 100 Wh usually fall under a “reasonable for personal use” policy. That covers a few slim chargers for phones and cameras. For the 101–160 Wh group, most rules cap spares at two per traveler with approval. Airlines may also cap the total number of loose batteries in the cabin when a group travels with lots of gear.
Region And Airline Differences
Rules are harmonized, but carrier policies can be stricter. A few airlines publish extra steps for smart luggage with built-in packs: detach the battery and carry it in the cabin, with the contacts taped or in a sleeve. If the Wh rating is missing or unreadable, staff may refuse the bag or the pack.
Before you fly, skim your airline’s page on batteries and chargers. Large carriers link straight to the rule pages from aviation bodies. Two good references many airlines cite are the FAA’s “Pack Safe” charts and IATA’s lithium battery guidance.
Packing Steps That Speed Screening
Neat packing reduces questions at the X-ray belt and at the gate. Use these steps when you travel with portable chargers.
Step-By-Step Packing
- Place power banks in a small pouch in your daypack, not in hold luggage.
- Cover exposed terminals with tape if the pack has posts. Many slim banks don’t, so a sleeve is enough.
- Carry the charging cable separately so staff can see the device clearly.
- Use the power button to switch the pack off before boarding. Many banks have a tiny switch.
- Do not charge devices during taxi, takeoff, or landing. Wait until the seat belt sign is off.
- Keep the pack on the tray or seat pocket while in use. Never charge inside a bag.
Close Variation Heading: Power Bank Size Rules For Air Travel
This section gathers the thresholds and the “do/don’t” list in one place, so you can match your charger to the right lane and avoid last-minute hassle.
Allowed, Approval-Only, And Banned
- 0–100 Wh: Allowed in cabin bags. No airline approval needed for consumer packs. Quantity should align with personal use.
- 101–160 Wh: Allowed in cabin with airline approval. Up to two spares per person in many policies.
- Over 160 Wh: Not allowed in passenger baggage. Ship by cargo under battery shipping rules if you must move it.
Why Wh, Not mAh?
Watt-hours measure stored energy, which maps to fire risk and heat release. Milliamp-hours alone don’t account for voltage. Two packs with the same mAh can store different energy if their cell voltages differ. That’s why airlines ask for Wh on the label.
What About Devices With Built-In Batteries?
Laptops, tablets, phones, and cameras ride in the cabin. Packs that are built into bags or suitcases must be removable. If the pack can’t be removed, staff may deny the bag at check-in.
When Your Pack Has Multiple Cells
Many power banks string several 18650 or 21700 cells together. The maker calculates total Wh by adding the cell energy. You don’t need to open the case; use the printed Wh figure. If you build your own pack, label it. A plain box with no specs invites a stop at screening.
How Airlines Check Quantity And Approval
Gate staff look for a note in the booking, the Wh label, and proper protection. If you have two large spares, expect staff to ask to see both. Teams carrying camera gear should split packs across travelers so one person isn’t over the per-person cap.
Table: Rule Snapshot By Wh Band
Here’s a compact snapshot you can use when packing for a trip with chargers and spare cells.
| Wh Range | Airline Approval | Max Spares |
|---|---|---|
| 0–100 Wh | Not needed | Reasonable personal use |
| 101–160 Wh | Required | Up to two |
| >160 Wh | Not allowed | None |
Real-World Picks That Fit The Rules
Shopping for a new charger? A unit around 20,000 mAh (≈74 Wh) hits a sweet spot: enough juice for phones and a tablet, still well under the limit, and light in the bag. Frequent flyers who need laptop top-ups often aim for 26,800 mAh (≈99 Wh) to squeeze every Wh under the cap. Larger bricks can work if you secure airline approval, but check weight and charging needs before you go that route.
What To Do If Security Flags Your Pack
Stay calm and show the label. If the Wh rating isn’t printed, show a spec sheet on your phone or a receipt with the Wh listed. If the unit lacks markings and looks oversized, screeners may take it. Losing a pack stings less than missing a flight.
Authoritative Sources You Can Show Staff
You can point staff to two clear rule pages mid-trip if needed. The FAA’s Pack Safe lithium battery chart lays out the 0–100 Wh and 101–160 Wh bands and the ban above that. The TSA’s page on power banks in carry-on states that portable chargers ride in the cabin only. For international alignment and mAh-to-Wh examples, the IATA lithium battery guidance spells out the thresholds many airlines adopt.
Checklist Before You Leave For The Airport
- Pack chargers in hand luggage; never in hold luggage.
- Confirm the Wh rating is printed and under the correct band.
- Carry proof for 101–160 Wh units and get airline approval ahead of time.
- Protect terminals and pack each spare so it can’t short.
- Keep the unit visible when charging during the flight.
Bottom Line For Hassle-Free Travel
Keep power banks at or under 100 Wh for a smooth trip. If you must carry a larger pack, cap it at 160 Wh, get approval, and keep it in the cabin with terminals protected. Anything bigger stays off passenger flights. Markings, neat packing, and a quick read of your airline’s battery page save time at the checkpoint and at the gate.