Yes, two 20,000mAh power banks are allowed in carry-on bags because each is under 100Wh; never pack power banks in checked baggage.
Travelers carry power banks to keep phones, tablets, and cameras alive. The good news: two 20,000mAh packs meet common airline and regulator limits when placed in cabin bags. The guardrails are simple—keep them out of checked luggage, keep capacity under set watt-hour thresholds, and protect the terminals from short circuits. The sections below spell out the limits, show the conversion math, and give packing tips that pass gate checks with zero fuss.
Bringing Two 20,000mAh Power Banks On Flights: What The Rules Say
Power banks count as spare lithium-ion batteries. Global guidance lines up on a few core points:
- Carry-on only for all spare lithium-ion batteries and power banks.
- ≤100Wh per battery: normally permitted in cabin bags without special approval.
- 101–160Wh per battery: permitted in cabin bags with airline approval; capped at two spares.
- >160Wh: not allowed for passengers.
A typical 20,000mAh pack is rated at 3.6–3.85V cells; most labels round to 3.7V. That puts a 20Ah pack at about 74Wh (see the watt-hour formula below). Two such packs sit well below the 100Wh line.
Quick Reference: Capacity To Watt-Hours And Allowance
This table helps you map mAh to Wh so you can see where your power bank lands. It uses 3.7V, the common nominal voltage for lithium-ion cells used in consumer packs. Always check the label on your unit; if it shows Wh directly, use that value.
| Labelled Capacity (mAh) | Approx. Wh (at 3.7V) | Typical Allowance |
|---|---|---|
| 10,000mAh | 37Wh | Carry-on allowed; no airline approval |
| 20,000mAh | 74Wh | Carry-on allowed; no airline approval |
| 26,800mAh | ~99Wh | Carry-on allowed; no airline approval |
| 30,000mAh | ~111Wh | Carry-on with airline approval (max two spares) |
| >43,000mAh | >160Wh | Not permitted for passengers |
Why Two 20,000mAh Packs Are Fine In Cabin Bags
A 20,000mAh bank sits under 100Wh, which is the widely used limit for free carriage of spare lithium-ion batteries in hand luggage. Multiple regulators and airline pages align on this threshold. You may carry more than one sub-100Wh bank; many airlines allow several, and some follow counts near the IATA baseline for spares. Pack them so terminals can’t touch metal and you’re set.
Watt-Hour Math: Proving Your Pack Is Under 100Wh
Airline staff may ask how you know the watt-hours. If the label shows Wh, point to it. If it shows only mAh and V, use this quick formula:
Wh = (mAh ÷ 1000) × V
For a 20,000mAh bank at 3.7V: (20,000 ÷ 1000) × 3.7 = 74Wh. That lands under the 100Wh line, which is why two such packs in your backpack are acceptable for most carriers.
Carry-On Only: No Power Banks In Checked Baggage
Rules call out a clear line: spare lithium-ion batteries—including power banks—cannot ride in the hold. Fire risk management is the reason. Cabin crew can spot and respond to a thermal event in the cabin; buried in the hold, that risk changes. Keep every power bank in your personal item or overhead-bin bag.
Official Rules You Can Point To
If you need a page to show at the desk, these are the gold-standard references mid-article so you can spot them fast:
- TSA: Power banks are carry-on only.
- FAA PackSafe: 100Wh baseline; two spares for 101–160Wh.
- IATA passenger guidance: carry-on only for spares; quantity limits.
Regional pages reach the same conclusion. The UK regulator’s site echoes the carry-on-only rule and outlines the two-spare cap for batteries over 100Wh.
What About Airline Policies And New Cabin Use Rules?
Airlines apply the same Wh thresholds, then add handling rules. Two trends matter this year:
- Use restrictions during flight. Some carriers now ask you not to use or charge a power bank while it’s buried in a bag or out of sight. The aim is quick access if a unit overheats. Keep any active charger visible—on the tray table or in a seat pocket—if your airline publishes this rule.
- Approval for 101–160Wh spares. If you carry big bricks near 30,000mAh, many airlines treat their acceptance as pre-approved once you meet the count and packing rules. Always check your booking’s “dangerous goods” page.
Flying with two 20,000mAh units avoids those extra approval steps, since each is under 100Wh.
How Many Under-100Wh Power Banks Can You Bring?
Policy language varies. A common model follows the IATA guidance, which caps total spare batteries at a high number for personal use, with a separate cap of two for 101–160Wh packs. Many airlines don’t post a hard limit for sub-100Wh spares beyond “reasonable for personal use.” Two 20,000mAh units fit neatly within that range.
Packing Checklist That Passes Gate Checks
Use this step-by-step flow when you pack, then again at security:
- Confirm the label. Check your power bank’s Wh rating. If only mAh is listed, run the quick formula above.
- Cabin bag only. Place every power bank in a backpack, laptop bag, or carry-on roller. None in checked baggage.
- Protect the terminals. Keep each unit in a sleeve, zip pouch, or original box. If the bank has exposed pins, cover them with a cap or tape.
- Use a pouch for cables. Prevent metal parts from rubbing against ports.
- Turn it off. If your bank has a switch or screen, power it down in transit.
- Keep charging visible. If you charge in flight, follow your airline’s visibility rule. Don’t leave a live bank running in a closed bag or overhead bin.
Edge Cases: Fast-Charge Beasts, Laptop Banks, And Smart Suitcases
Some high-output units list large mAh numbers, GaN bricks, or laptop-class ratings. The label still rules. If the Wh tips past 100, you enter the “two spares with airline approval” lane. If Wh exceeds 160, leave it at home or ship by ground. For smart luggage with a removable bank, detach the battery and carry it in the cabin; if the pack can’t be removed, many airlines won’t accept the bag at drop-off.
Common Reasons Power Banks Get Stopped
Most delays trace back to labeling and packing. Here are the usual snags and how to avoid them:
- No clear Wh on the case. Bring a photo of the spec sheet or box if the shell only shows marketing claims. Staff accept Wh shown in the manual or spec label.
- Exposed terminals. Loose banks mixed with coins or keys can trigger extra checks. Use a sleeve or small zip bag.
- Damaged or swollen pack. Don’t fly with it. Dispose of it at a battery recycling point before travel.
- Charging out of sight. New cabin rules from some airlines ask you to keep any working charger visible. If in doubt, stop charging during taxi, takeoff, and landing.
Real-World Scenarios And Answers
Two 20,000mAh Units In A Backpack
Clear carry-on case. Each sits at ~74Wh. Place them in separate pouches. Security may ask you to pull them out like laptops. That’s normal.
One 26,800mAh And One 10,000mAh
Still fine. The larger unit is ~99Wh. Both are under 100Wh. Carry them both in hand luggage.
One 30,000mAh Pack
Near ~111Wh. That pushes you into the “101–160Wh” lane. Many carriers allow up to two spares in this band with approval. Check your airline’s site ahead of time and bring a screenshot of the policy page.
Safety Basics Every Flyer Should Follow
- Buy labeled gear. Reputable brands print Wh, mAh, and voltage. If the case has no specs, skip it for air travel.
- Use original cables. Cheap cords overheat and strain the bank’s protection circuit.
- Watch for heat. Warm to the touch during charging is normal; too hot to hold is not. Unplug and flag a crew member if you see smoke, swelling, or a burning smell.
- Store at mid charge. Around half charge during long travel days helps battery health.
Region-By-Region Snapshot
The baseline rules stay consistent across regions. This snapshot keeps it concise for trip planning.
| Source/Region | Core Rule | Notes |
|---|---|---|
| United States (TSA/FAA) | Spare lithium-ion & power banks: carry-on only; ≤100Wh allowed without approval | 101–160Wh: up to two spares with airline approval; none in checked bags |
| IATA (Global Model) | Spare batteries including power banks in cabin only | Commonly up to 20 spares overall; two spares when 101–160Wh |
| UK/Europe (CAA/EU carriers) | Carry-on only for spares; ≤100Wh free to carry | 101–160Wh: up to two spares with approval; airline pages may add usage notes |
What To Do If A Screener Questions Your Pack
Stay calm and show the label. If the shell lists only mAh and V, do the math on your phone: (mAh ÷ 1000) × V. If the unit lands under 100Wh, state that it’s a spare battery and belongs in the cabin. If staff still have doubts, show the regulator page from the links above. Clear labeling and tidy packing resolve most checks in under a minute.
Buying A Power Bank For Frequent Flyers
Pick a model that publishes Wh on the case. Target 10,000–26,800mAh to stay under the 100Wh line. Look for short-circuit, over-current, and temperature protections in the spec sheet. A simple pouch and a right-angle cable make tray-table charging neat and visible when airlines ask for it.
Travel-Day Checklist You Can Save
Before You Leave Home
- Check the label: Wh under 100 for smooth sailing with two units.
- Charge to ~50–80% for a long day; avoid stuffing a bank that’s already hot into a pack.
- Pack each bank in a separate pouch; add a cable tie to keep cords tidy.
At The Airport
- Keep power banks in an easy-reach pocket; be ready to place them in a tray if asked.
- Skip gate-side charging from a power bank if your airline asks to keep charging visible.
On The Plane
- Charge only when the bank is in sight; never leave a live bank inside an overhead bin or under a seat.
- If a bank overheats, unplug it, place it on a hard surface, and call a flight attendant.
Recap For Travelers: Two 20,000mAh Banks Are Travel-Friendly
Two 20,000mAh packs are well under the 100Wh threshold and travel in cabin bags without extra forms. Keep every spare battery in carry-on, protect the ports, and follow any airline use notes about visible charging. With those basics set, you’ll breeze through security and land with plenty of juice for maps, rides, and check-ins.