The CAA is the UK's aviation safety regulator, and its guidance is clear on one point above all: e-cigarettes and vaping devices must be carried only in the cabin, either on your person or in your hand luggage. Unlike a phone or a laptop, a vape is never allowed in hold luggage, because a damaged or short circuited lithium battery in the hold cannot be reached and dealt with quickly if something goes wrong.

Two further rules follow from that. First, the device and its batteries must not be recharged on board the aircraft, and passengers are expected to take steps to stop the heating element switching on by accident during the flight, for example by keeping a mod or pod kit switched off or locked. Second, every lithium battery used in a vape has to meet aviation safety limits of 2g of lithium metal or 100Wh for a lithium-ion cell, tested to the same UN38.3 standard applied to batteries in phones and laptops.

None of this is vaping specific red tape. It is the same lithium battery safety framework that applies to any small rechargeable device passing through a UK airport, and it sits well outside the Tobacco and Vapes Act 2026 rules we have covered elsewhere on this blog.

UK airport security applies the same liquids rule to e-liquid and nic salts as it does to any other liquid. Each container is limited to 100ml, and all of your liquid containers together need to fit inside a single transparent, resealable bag holding no more than a litre, roughly 20cm by 20cm, which you present separately at the security tray.

This is straightforward if you are travelling with 10ml nic salt bottles, since several can fit in the bag alongside your other toiletries with room to spare. It is worth checking before you pack, though, if you normally buy in a larger format such as a 100ml shortfill, since some 100ml bottles sit right at the container limit and larger multipacks will need to go in hold luggage instead of your cabin bag.

A sensible habit for regular travellers is to keep a small travel stock of 10ml bottles specifically for flights, rather than trying to squeeze a full size collection into hand luggage each time.

• Pack your vape and any spare batteries in your hand luggage, never in a checked bag, and keep spares to two or fewer with the terminals protected.
• Charge your device fully before you travel. Security staff can ask you to switch on an electronic item, and if it does not turn on you will not be allowed to take it through.
• Keep 10ml e-liquid and nic salt bottles in your one litre resealable liquids bag alongside your other toiletries, and pack any larger bottles in hold luggage instead.
• Do not vape, recharge, or top up nicotine at any point during the flight, including in the toilets.
• If you are travelling abroad, check the rules of your destination country separately, since several countries restrict or ban vaping devices entirely regardless of what UK rules allow.
• Our travel and airports guide and batteries and charging guide cover more everyday scenarios in detail.