There is almost certainly a portable charger somewhere in your travel bag right now. If you fly with any regularity, you probably own at least one, possibly several. They have become as essential to modern travel as a passport and a boarding pass, solving the problem of a dying phone battery during a long layover or a transatlantic flight with no functioning seat power outlet. The power bank is ubiquitous, inexpensive, and completely taken for granted.
It is also responsible for a growing number of in-flight emergencies, airport evacuations, and flight diversions, and the airlines that carry you across the world have responded with rules that are more detailed, more specific, and more strictly enforced than most American travelers realize. A recent incident involving an EasyJet flight from Egypt to London illustrates exactly how serious the consequences can get. The flight was diverted to Rome mid-journey after a power bank was discovered charging in a passenger’s checked luggage. The aircraft had to make an unscheduled landing, passengers were delayed significantly, and the situation required intervention before the flight could continue.
The passenger almost certainly did not intend to create an emergency. They packed their power bank without thinking carefully about where it went or what state it was in, and the result was a diversion that affected everyone on board. Understanding why power banks are treated as high-risk items by aviation authorities, and what the specific rules are across the major airlines that American travelers use for European trips, is information that takes minutes to absorb and can prevent exactly the kind of incident that turns a routine flight into an unexpected overnight in the wrong city.
Why Power Banks Are a Genuine Fire Risk in the Air
The danger that portable chargers present on commercial aircraft is not a regulatory overcaution or a theoretical concern developed by lawyers. It is a documented, physics-based risk that has produced real incidents at airports and on flights around the world in recent years.
Power banks use lithium-ion batteries, the same technology that powers smartphones, laptops, and electric vehicles. Lithium-ion batteries store significantly more energy per unit of weight than older battery technologies, which is what makes them useful for powering devices through long periods without access to an outlet. That same energy density is what makes them dangerous when something goes wrong.
When a lithium-ion battery is damaged, short-circuits, gets wet, or is overcharged, the cells can enter a state called thermal runaway. This is not simply overheating. It is a self-sustaining chemical reaction that rapidly generates extreme heat, can produce flames, and in severe cases results in an explosive release of energy. Fire authorities describing the phenomenon compare it to multiple fireworks igniting in rapid succession inside a confined space. Once thermal runaway begins in one cell, it can spread to adjacent cells, amplifying the reaction rather than limiting it.
In a controlled environment on the ground, a thermal runaway event involving a single power bank is serious but manageable. On a commercial aircraft at cruising altitude, it is a fundamentally different situation. At altitude, the options for managing a fire are limited. The proximity of passengers, the aircraft structure, and the fuel that powers the plane make any fire event significantly more dangerous than the equivalent event on the ground.
In the aircraft hold, where checked luggage travels, the situation is worse still. The hold is not occupied by crew members who could observe and respond to a fire early. Hold fires can grow significantly before they are detected. This is precisely why power banks are prohibited from checked luggage not just by the airlines mentioned here, but by aviation safety authorities across the world, including the FAA in the United States.
Real incidents reinforce why these rules matter. An exploded power bank caused an evacuation at Melbourne Airport in 2025. South Korean airline Air Busan attributed a fire that destroyed one of its aircraft to a portable power bank. These are not isolated anomalies. They are part of a documented pattern of incidents involving lithium-ion batteries in aviation settings that has been tracked by safety organizations and driven the increasingly specific rules now in place.
The Universal Rules That Apply Regardless of Which Airline You Fly
Before getting into the airline-specific variations, it is worth establishing the baseline rules that apply across all commercial aviation. These are set by international aviation safety standards and are in force whether you are flying a budget European carrier, a major transatlantic airline, or any other commercial operator.
Power banks must travel in carry-on luggage. This is the foundational rule, and it is absolute. No power bank, regardless of its size, brand, or condition, belongs in checked luggage. The reason is the thermal runaway risk: in the cabin, where crew and passengers can observe a device, any thermal event can be detected and responded to immediately. In the hold, it cannot.
Passengers are limited to a maximum of two power banks per person. This limits the total amount of lithium-ion battery energy any single passenger introduces into the cabin, which reduces the aggregate risk across a fully loaded aircraft.
Power banks must not be used to charge other devices while on board the aircraft. The act of charging a device generates heat in the battery, and that heat increases the risk of thermal issues. Keeping power banks in a passive state during flight reduces the likelihood of any incident.
Power banks must not be charged on board. Charging a power bank generates even more heat than using it to charge another device, and doing so in an aircraft cabin is prohibited universally.
Regarding capacity limits, power banks under 100 watt-hours can generally be carried without requiring special approval. Power banks between 100 and 160 watt-hours require airline approval before travel. Power banks above 160 watt-hours are not permitted on commercial aircraft under any circumstances. Most consumer power banks sold for general travel fall well below 100 watt-hours, but higher-capacity units marketed for extended travel or laptop charging can approach or exceed the threshold. Checking the watt-hour rating, which is typically printed on the device or on its packaging, before travel is essential.
When not in use, power banks must be individually protected against short circuits. This means keeping terminals covered, either through original packaging, terminal tape, or placement in a protective case or plastic bag that prevents contact with other conductive items.
How the Rules Vary Across Major European Airlines
The baseline rules above establish the universal framework, but several major European airlines that American travelers use regularly for transatlantic trips and intra-European connections have added specific requirements on top of that baseline. Knowing what your specific carrier requires, rather than assuming all rules are identical across airlines, is important preparation before any trip.
Jet2, which operates flights across Europe and is widely used by travelers connecting through UK airports, takes a specific position on watt-hour rating transparency. The airline prohibits power banks that do not clearly display a watt-hour rating, or from which the watt-hour rating cannot otherwise be reasonably determined. If you have an older or unbranded power bank without a visible capacity rating, Jet2 will not allow it on board regardless of its actual capacity. The policy addresses the practical reality that unrated or unlabeled batteries cannot be assessed for compliance with capacity limits, and the airline has taken the position that unverifiable means unacceptable.
Ryanair’s specific requirements direct passengers to place power banks and other spare lithium batteries in small cabin baggage stowed under the seat in front, rather than in overhead bin luggage. The carrier has also set a 100 watt-hour limit for power banks without requiring pre-approval, which is more conservative than the general 100-to-160-watt-hour approval window in the universal rules. For American travelers who carry higher-capacity power banks for long-haul trips, Ryanair’s tighter limit means certain devices that would be acceptable on other carriers may not be permitted on Ryanair flights. The under-seat placement requirement rather than overhead bin storage also reflects a philosophy of keeping high-risk items where they can be monitored and quickly accessed rather than stored above head height where a fire event would be harder to manage.
British Airways, one of the primary carriers for Americans flying directly between the United States and the United Kingdom, requires passengers to place power banks under 110 watt-hours in the seat-back pocket of the chair in front of them or in a bag under the seat. Like Ryanair, British Airways prefers under-seat storage over overhead bins for power banks specifically. The 110 watt-hour limit without pre-approval is slightly more generous than Ryanair’s but still more conservative than the 160-watt-hour universal ceiling.
EasyJet, whose recent flight diversion brought power bank rules into sharp focus, allows power banks up to 160 watt-hours, aligning with the universal maximum. However, EasyJet adds a specific condition that American travelers should note: power banks subject to a safety recall related to their battery technology must not be carried on board regardless of their watt-hour rating. If a power bank model you own has been recalled for battery safety issues, EasyJet’s rules require you to leave it at home even if it has not exhibited any problems. Checking whether your specific power bank model is subject to any active recalls before travel is a step that EasyJet is explicitly requesting.
TUI, which operates package holidays and flights across European routes popular with American travelers, has two specific requirements beyond the baseline. Power banks must be individually protected against short circuits by being carried in their original packaging with terminals covered, in a bag that isolates them from other items, or with terminals taped. This is the same individual protection principle in the universal rules, but TUI is specific about what individual protection means in practice. Additionally, TUI requires that power banks be completely switched off during travel, not simply in standby mode or hibernation. A device that is technically off but can resume operation automatically is not considered fully off under TUI’s interpretation, and the carrier requires a complete power-off state.
Virgin Atlantic has requirements that are particularly relevant for American travelers given its transatlantic routes. For power banks above 100 watt-hours and under 160 watt-hours, Virgin requires airline approval obtained in advance through its customer service, not at the gate or check-in counter. Americans carrying high-capacity power banks for long-haul flights who plan to fly Virgin should contact the airline before travel day to secure approval rather than discovering the requirement at the airport. Virgin also requires that power banks be in good condition with no visible signs of damage, and the carrier has a specific dimensional requirement: the power bank must fit within an onboard fire containment bag measuring 37 by 28 by 10 centimeters. If your power bank exceeds those dimensions, it may not be accommodated regardless of its watt-hour rating.
The Watt-Hour Question That Confuses Most Travelers
The watt-hour capacity system that governs power bank rules is unfamiliar to most American consumers, who typically think of power bank capacity in milliamp-hours, the unit most commonly displayed on packaging and devices. Understanding how to convert between the two, or how to find the watt-hour rating directly, prevents the confusion that can arise at an airport check-in counter when an agent asks for the watt-hour rating of a device and the traveler has no idea where to find it.
The watt-hour rating is calculated by multiplying the milliamp-hour capacity by the voltage of the battery and dividing by 1,000. A common consumer power bank might be rated at 20,000 milliamp-hours at 3.7 volts, producing a watt-hour rating of 74. That device falls comfortably below the 100 watt-hour threshold and requires no approval on any of the airlines discussed here.
A high-capacity power bank rated at 30,000 milliamp-hours at 3.7 volts produces a watt-hour rating of 111, which exceeds the 100-watt-hour threshold and requires approval on airlines including Ryanair and British Airways, and requires advance contact with Virgin Atlantic. Knowing this before arriving at the airport allows the traveler to either arrange approval in advance or make a decision about whether to pack a different, smaller device.
Most modern power banks display the watt-hour rating directly on the device or its packaging alongside the milliamp-hour rating. If yours does not, the calculation above provides the answer. Jet2’s position that unlabeled devices are simply prohibited rather than subject to calculation underscores why keeping a power bank in its original packaging, with its specifications clearly visible, is the simplest approach for maintaining compliance across different carriers.
The Practical Habits That Keep You on the Right Side of Every Airline’s Rules
The variations between airline-specific rules are real but navigable, and the underlying logic across all of them is consistent: keep power banks in the cabin where they can be monitored, keep them protected and inactive during flight, and know the capacity of what you are carrying.
Carrying power banks in a bag stored under the seat rather than in an overhead bin is a practice that satisfies the explicit requirements of several carriers, including Ryanair and British Airways, and represents a generally safer approach that makes your device more accessible if anything unexpected occurs. Getting into this habit regardless of which airline you are flying removes the need to remember different storage requirements for different carriers.
Covering power bank terminals before travel, whether with tape, original packaging, or a dedicated protective case, satisfies both the individual protection requirement in universal rules and the specific requirements of carriers including TUI. A small piece of electrical tape over the terminals takes seconds to apply and eliminates the short-circuit risk from contact with keys, coins, or other conductive items in a carry-on bag.
Fully powering down power banks before passing through security and before boarding, rather than leaving them in standby, addresses TUI’s specific requirement and is a generally prudent practice regardless of which airline is operating the flight.
For high-capacity devices, checking the watt-hour rating and contacting airlines like Virgin Atlantic in advance when that rating falls between 100 and 160 watt-hours is the responsible approach that prevents gate-day surprises. The investment of a brief phone call or email to the airline’s customer service before travel day is considerably less disruptive than discovering at check-in that your device requires pre-approval you have not obtained.
The EasyJet flight diversion to Rome is the most recent visible reminder of what happens when these rules are not followed. No single traveler who packed a power bank in checked luggage intended to divert a flight and strand passengers. The rules exist because the risk is real, the consequences when things go wrong are severe, and the compliance cost is genuinely minimal compared to what noncompliance can produce.
