Liquids and airport security: why the rule keeps changing

The rule is set by the airport, not the airline. That single fact explains why your outbound and your return can work differently, and why the internet disagrees with itself about it.

✓ Last checked 20 September 2026 By Oliver Jones Independent — we sell nothing

Who actually decides

Passengers reasonably assume the airline sets the rules, because the airline sold them the ticket and emails them about everything else. It does not.

Cabin security screening is run by the airport, under rules set by the national aviation authority. In the UK that is the Department for Transport and the Civil Aviation Authority. In Spain, Greece or Turkey it is their equivalent.

Three consequences follow, and all three catch people out.

Your airline cannot tell you. Its website will give generic guidance. It has no authority over the queue you are standing in.

Two airports on the same trip can differ. You might clear security at home with a litre of sun cream and be told at the other end that it is 100ml only.

It changes. UK airports have been installing new scanners that can clear larger containers, the rollout has run at different speeds, and limits have been relaxed and then reimposed more than once during it.

What counts as a liquid

Wider than most people expect. Security treats as a liquid anything that pours, spreads, sprays or squeezes:

• drinks, including water you bought ten metres earlier
• toiletries: shampoo, conditioner, shower gel, sun cream, aftersun
• cosmetics: foundation, mascara, lip gloss, nail varnish
• pastes and gels: toothpaste, hair gel, deodorant sticks of the gel type
• soft foods: yoghurt, honey, jam, soft cheese, hummus
• aerosols of any kind

The ones that surprise people are the last two groups. Toothpaste is a paste. A jar of local honey bought on holiday is a liquid. Both get taken off you.

The exemptions worth knowing

Prescription and essential medicine is exempt from the volume limit. Carry it in its original packaging, bring the prescription or a letter from your GP, and declare it before you go through rather than after. Expect it to be screened separately, which takes a minute and is entirely routine.

Baby food, formula and expressed milk are exempt in the quantity needed for the journey. You may be asked to taste it. Bring it in containers you can open.

Liquids bought airside, after security, are not subject to the limit for that flight. They may be subject to it at your next airport if you are connecting, which is why duty-free bought on the outbound sometimes gets confiscated on the way home.

Packing so the queue is short

1. Put the bag at the top of your case, not at the bottom under the clothes. You will be asked for it.
2. Decant at home. Travel-sized bottles cost almost nothing and remove the decision entirely.
3. Buy the bulky things there. Sun cream, shampoo and shower gel are available in every resort in Europe, usually cheaper than at a UK airport.
4. Empty your water bottle before the queue, then fill it from a fountain airside. Most terminals have them now.

Coming home is the harder direction

This is the asymmetry nobody plans for.

On the way out you packed deliberately. On the way home you have a jar of olive oil, a bottle of local wine someone gave you, a half-used litre of aftersun and three jars of honey, and you are at an airport whose rules you have not read.

If you have hold baggage, put all of it in the hold. If you are travelling hand luggage only, decide at the hotel, not at the scanner.