A power bank is one of the most useful things to pack for a trip – but lithium batteries come with specific rules for air travel. Here's what UK travellers need to know before heading to the airport.
The key rule: hand luggage only
Spare lithium batteries, including power banks, must be carried in your hand luggage. They are not allowed in checked (hold) baggage. If your bag is taken from you at the gate to go in the hold, remove the power bank first.
Check the watt-hour (Wh) rating
Airlines set limits in watt-hours (Wh), not milliamp-hours (mAh). Many power banks print the Wh figure on the casing. If yours only shows mAh, you can estimate it:
Wh = (mAh × voltage) ÷ 1000. Most power banks use 3.7V cells, so a 10,000mAh power bank is about 37Wh and a 20,000mAh power bank is about 74Wh.
- Up to 100Wh (roughly up to 27,000mAh at 3.7V): generally allowed in hand luggage on most airlines.
- 100Wh to 160Wh: usually needs the airline's approval in advance, and there is often a limit of two.
- Over 160Wh: not allowed on passenger aircraft.
Rules vary between airlines and some limit how many power banks you can carry or ban using them on board, so always check your airline's website and the UK Civil Aviation Authority guidance before you fly.
Tips for flying with a power bank
- Choose a power bank that clearly shows its capacity on the casing.
- Protect the ports from short circuits – keep it in a pouch or its original box.
- Don't charge it on board unless the crew say it's allowed.
- A 10,000mAh magnetic power bank is a great all-rounder for a phone on a day out or a short trip.
Find the right size for your trip in our power bank collection, from slim magnetic packs to high-capacity models – with free tracked UK delivery.