The Best Power Bank for Flying: Stay Under 100Wh and You Never Have to Ask

A compact gray power bank charging a smartphone by a short cable on an airplane tray table, next to a paper coffee cup and the window.

⚖️Disclosure: MyVivaVitality is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program. If you buy something through a link on this page we may earn a small commission, at no extra cost to you. It never changes which power bank we recommend — the biggest one on this page is the one we tell you to leave at home.

A dead phone at the gate is a small disaster. Your boarding pass is on it, your ride is on it, and the one outlet at the gate has four people standing around it.

A power bank fixes that, but flying adds one rule that most people have never looked at. The FAA limits lithium-ion batteries in the cabin to 100 watt-hours (Wh) each. Between 101 and 160Wh you need the airline’s approval, and you can carry two at most. Above 160Wh, it isn’t allowed on a passenger plane at all.

The catch is that power banks are sold by milliamp-hours (mAh), not watt-hours. So here’s how to translate, and five power banks compared against the line.

Every power bank in this guide, at a glance
Power bankCapacityAboutBest forThe catch
Anker Nano10,000mAh37WhA phone, with nothing to forgetAbout two phone charges
INIU 20,000mAhOur pick20,000mAh74WhMost travelers: phone plus tabletTwice the weight of a 10K
Anker 73724,000mAh89WhCharging a laptopA brick
Anker Prime26,250mAh99.75WhThe most you can carry without askingNo margin under 100Wh
50,000mAh “camping” bank50,000mAh185WhCamping, power outagesNot allowed on a plane

Everything above the last row flies without a second thought. The last row doesn’t fly at all.

How to turn mAh into watt-hours

Most power banks use lithium-ion cells rated around 3.7 volts. The math is:

mAh × 3.7 ÷ 1,000 = Wh (roughly)

  • 10,000mAh is about 37Wh
  • 20,000mAh is about 74Wh
  • 26,800mAh is about 99Wh, which is the practical ceiling
  • 50,000mAh is about 185Wh, which is over every limit

Newer power banks print the exact Wh on the case. If yours does, that number wins. If it doesn’t, the rough math tells you which side of the line you’re on.

Where each power bank lands against the FAA limits Watt-hours from mAh x 3.7 / 1,000 unless the listing prints the Wh. Limits from the FAA’s PackSafe rules for spare lithium-ion batteries. Fine in your carry-on Airline approval, max 2 Not allowed Anker Nano 10,000mAh about 37Wh INIU 20,000mAh (our pick) about 74Wh Anker 737 24,000mAh about 89Wh Anker Prime 26,250mAh 99.75Wh (listed) A 50,000mAh “camping” bank about 185Wh 100Wh 160Wh 0

Four of the five sit under the 100Wh line. The fifth isn’t just over a limit; it’s over the ceiling, and security will take it from you.

Three rules people miss

  • Power banks go in your carry-on, never in checked bags. If your carry-on gets checked at the gate, take the power bank out first. That’s an FAA rule, not an airline preference.
  • Protect the ports. The terminals must be protected from short circuits. A pouch or the pocket of your bag is enough; loose in a bag full of keys and coins isn’t.
  • Airlines can be stricter. Some limit how many power banks you can bring, and some now restrict using them during the flight. Check your airline before you fly.
Hands placing a power bank in a mesh pouch into the front pocket of a carry-on backpack at an airport gate.
Right bag, right pocket. In a pouch the ports are protected, and in the carry-on it stays with you even if the bag gets checked at the gate — as long as you take it out first.

If you’re flying carry-on only this season, see our guide to carry-ons that actually fit the US size limit.

Amazon pricing moves constantly, so check the current figure before you buy. Here are the five, from smallest to largest.

Three gray power banks side by side on a travel backpack, from a slim one with a built-in cable to a large brick.
Capacity you can see. The slim one on the left covers a phone for a travel day; the brick on the right is laptop territory, and every gram of it comes with you.

Anker Nano Power Bank 10,000mAh with Built-in USB-C Cable

Lightest for a phone

This is the one for phone-only travelers who want the least to carry.

Right for
Keeping a phone alive through a travel day. At about 37Wh it’s nowhere near the limit, and the USB-C cable is built into the body, so there’s no cable to forget.
Skip it if
You need to charge a laptop, or you want several full phone charges on a long trip.
The drawback
10,000mAh is roughly two phone charges at best. On a trip with long days away from outlets, you’ll run it flat.
Check price on Amazon

INIU 20,000mAh 45W Power Bank with Built-in USB-C Cable

Our pick for most travelers

This is the one I’d buy for most travelers.

Right for
A phone plus earbuds or a tablet across a long travel day, or a weekend without charging the bank itself. At about 74Wh it sits comfortably under the 100Wh line, and it also has a built-in cable.
Skip it if
You need to charge a laptop at full speed. 45W will keep many laptops going, but not charge a big one quickly.
The drawback
It’s twice the weight of a 10,000mAh bank. You’ll notice it in a jacket pocket.
Check price on Amazon

Anker 737 Power Bank (24,000mAh, 140W)

For charging a laptop

This is the pick for charging a laptop.

Right for
Travelers who work on the plane or in the airport. With up to 140W of output it can charge a laptop quickly, and at about 89Wh it’s still under the 100Wh limit. The built-in display shows exactly how much charge is left.
Skip it if
You only charge a phone. You’d be carrying laptop-class weight for a phone-class job.
The drawback
Size and weight. It’s a brick, and it’s more power bank than most people need.
Check price on Amazon

Anker Prime Power Bank (26,250mAh, 300W)

The most you can carry without asking

This is as big as a power bank can be without asking the airline.

Right for
Creators and heavy laptop users who want the most capacity the rule allows. Anker lists it at 99.75Wh, a quarter of a watt-hour under the line, with up to 300W across its ports.
Skip it if
You don’t need to charge several devices at laptop speeds. Most travelers never will.
The drawback
It’s premium-priced and heavy, and at 99.75Wh there’s no margin at all. If an airline sets a lower limit than the FAA’s, this is the first bank to fall foul of it.
Check price on Amazon

The 50,000mAh “camping” power bank

Not allowed on a plane
Right for
Camping and power outages, where you’ll never go near an airport.
Skip it if
You’re flying. That’s the point of this guide.
The drawback
At roughly 185Wh, it’s over the 160Wh ceiling, so it isn’t allowed on a passenger plane even with airline approval. These are often sold as “travel essentials,” and security will take it from you at the checkpoint.

What most people get wrong

They pack it in the checked bag. That’s the one place a power bank is never allowed. If a gate agent checks your carry-on, take the power bank out.

They trust “flight-safe” in the product name. Do the math, or read the Wh printed on the case. It takes ten seconds.

They buy for the worst case. A bank that can charge a laptop three times is heavy every day of the trip. Buy for what you actually charge.

They forget to charge the power bank. A dead power bank weighs the same as a full one. Top it up the night before you fly.

Here’s what I’d pick

The bottom line

For most travelers, get the INIU 20,000mAh. It keeps a phone and a tablet going through a long travel day, the cable is built in, and at about 74Wh it’s well under the limit.

If you only charge a phone and want the smallest thing possible, the Anker Nano is enough. If you work on a laptop while you travel, get the Anker 737.

Whatever you choose, keep it under 100Wh, keep it in your carry-on, and check your airline’s own rules before you fly.

Check price on Amazon