Best Phone Accessories for Travel: The Complete Packing Guide

Under official TSA and FAA guidance, a device with a built-in lithium-ion battery — a phone, laptop, or camera — can travel in either carry-on or checked baggage. Spare, uninstalled batteries are treated differently: power banks, portable chargers, and phone battery cases are all classified as spare batteries, and per TSA's own rule, they "must be carried in carry-on baggage only." This is not a minor technicality — it applies regardless of whether the power bank is switched off or wrapped for protection, and checking one is not a workaround.

The FAA sets the watt-hour tiers that determine what is allowed at all. Lithium-ion batteries rated 100 watt-hours or less travel without special airline approval. Batteries rated between 101 and 160 watt-hours require the airline's approval in advance and are limited to two spares per passenger. Anything above 160 watt-hours is prohibited on passenger aircraft entirely. Most phone-sized power banks fall comfortably under the 100 Wh threshold, but higher-capacity power banks marketed for laptops or multi-device charging can approach or exceed it — checking the watt-hour rating printed on the product, not just its advertised battery capacity in milliamp-hours, is the only reliable way to know which tier applies before you travel.

Effective March 27, 2026, the International Civil Aviation Organization introduced new restrictions on power banks that apply across all 193 member countries, according to independent aviation-industry reporting. The rule limits passengers to a maximum of two power banks in cabin baggage, requires that power banks be kept accessible rather than stored in an overhead bin during the flight, and prohibits charging a power bank in flight. Checked baggage remains off-limits for power banks entirely, consistent with the existing TSA and FAA rules.

Multiple major carriers have adopted versions of this restriction, reported to include Emirates, Qatar Airways, Singapore Airlines, Air India, Cathay Pacific, and British Airways, alongside the Lufthansa Group airlines (Lufthansa, SWISS, Austrian Airlines, and Brussels Airlines), which had already introduced a similar two-power-bank limit and in-flight charging ban. The stated safety rationale centers on a structural vulnerability specific to power banks: unlike a phone or laptop, a power bank typically has no active thermal management, temperature sensors, or software monitoring for unusual power draw, and reporting on the rule cites this gap — combined with the sheer number of lithium-ion devices aboard a typical wide-body flight — as the reason for the tightened restriction following specific in-flight incidents that prompted regulatory attention.

Power banks are almost always marketed by their capacity in milliamp-hours (mAh), but the aviation rules above are written in watt-hours (Wh) — and the two numbers are never equal, which causes real confusion at packing time. Watt-hours are calculated as capacity in amp-hours multiplied by the battery's nominal voltage: dividing the milliamp-hour figure by 1,000 to get amp-hours, then multiplying by the cell's nominal voltage, which for a standard lithium-ion cell is typically around 3.6 to 3.7 volts. A power bank advertised at 20,000 mAh, for example, works out to roughly 74 watt-hours (20 amp-hours multiplied by 3.7 volts) — comfortably under the 100 Wh threshold, even though "20,000" sounds like a much larger number than "74."

This is exactly why a shopper comparing power banks purely by mAh capacity can misjudge which watt-hour tier a product falls into. A responsibly labeled power bank prints its watt-hour rating directly on the housing, which is the number that actually matters for airline compliance — if only a milliamp-hour figure is visible, running the conversion above, or checking the manufacturer's specification sheet for the Wh figure directly, avoids an unpleasant surprise at the checkpoint.

This is one of the most commonly over-solved problems in travel packing. A plug adapter changes the physical shape of the plug so it fits a different country's outlets — it does nothing to the voltage itself. A voltage converter actually changes the electrical voltage, and is a heavier, bulkier, more expensive piece of equipment that most phone-charging travelers do not actually need. The distinction matters because most modern USB-C phone chargers use switch-mode power supply designs, which are generally built to accept a wide range of input voltages rather than one fixed voltage — a feature that specifically supports international use without a separate converter.

The reliable way to confirm this for your specific charger is to check the fine print on the charger itself, where the input voltage rating is printed — commonly shown as a range such as "100-240V." If your charger shows a range like that, you only need a plug adapter for the physical socket shape; if it shows a single fixed voltage instead, a converter may genuinely be necessary, though this is now uncommon for USB-C phone and tablet chargers specifically. This check takes a few seconds and avoids either an unnecessary converter purchase or, worse, plugging a fixed-voltage device into an incompatible outlet.

Charging accessories rarely cause problems at a security checkpoint, but a few habits make the process smoother. Cables, wall chargers, and plug adapters do not need to be removed from a carry-on bag for X-ray screening in most cases, since they contain no batteries and are not treated as a separate category the way laptops sometimes are. Power banks are the exception worth planning around: because they are classified as spare batteries, keeping them in an easily accessible pocket rather than buried at the bottom of a bag saves time if a screening officer wants to visually inspect one, which happens more often with power banks than with cables or basic chargers. As TSA's own guidance notes, the final decision on what is allowed through a checkpoint rests with the officer on duty, so a power bank without a clearly visible watt-hour rating printed on the housing can occasionally prompt extra questions even when it is fully compliant — buying one with the rating clearly marked avoids this minor friction.

It is also worth checking your destination country's own security and customs rules if you are traveling internationally, separate from the airline and TSA rules covered above — some countries apply their own restrictions on lithium batteries or electronics that go beyond the baseline US and ICAO rules, particularly for high-capacity power banks. A quick check of the relevant country's civil aviation or customs authority before departure is a more reliable source than assuming US rules apply everywhere you land.

Travel is one of the more demanding environments a phone case and any attached mount will see — being handled more often than usual, set down on unfamiliar surfaces, and occasionally dropped while juggling luggage. This guide is focused on charging and power rules rather than repeating the full case and magnetic-accessory buying guidance covered elsewhere, but the short version worth knowing before a trip: a case rated for drop protection is a reasonable trip investment even if you do not normally use one at home, and if you plan to use a magnetic mount in a rental car, the same certification checks covered in the companion magnetic accessories guide apply just as much on the road as at home.

A well-planned travel charging kit is usually smaller than people expect once the voltage question above is settled. One multi-port USB-C charger, sized to your most demanding device the same way the companion guide to charging multiple devices recommends, generally replaces several single-device chargers — useful given how much luggage space and weight several separate chargers otherwise take up. A plug adapter matched to your destination's outlet shape, one or two USB-C cables rated for the wattage your charger supports, and a single power bank sized under the 100 Wh threshold typically covers a full trip for most travelers, without needing to pack a backup for every accessory.

It is worth packing at least one spare cable regardless of trip length — cables are the most common casualty of travel wear, from luggage compression to repeated coiling and uncoiling, and are also the easiest and least expensive item to leave behind by accident in a hotel room or airport seat. A cable failure away from home is a considerably bigger inconvenience than a cable failure at home, where a replacement is a short trip away rather than a search in an unfamiliar city.