The 100 ml liquids rule
The Liquids, Aerosols, and Gels (LAGs) restriction is the most consistently misunderstood rule in aviation security. It applies at departure security checkpoints in the EU, UK, US, Canada, Australia, and most other major aviation markets. The core rule has three components, all of which must be satisfied simultaneously.
The three-part rule
100 ml
Each individual container must have a capacity of no more than 100 ml. A container larger than 100 ml is not permitted even if it is mostly empty.
1 L bag
All liquid containers must fit inside one transparent, resealable plastic bag with a total capacity of no more than one litre. The bag must be sealed and presented separately at the checkpoint.
1 bag
One bag per passenger. Multiple bags are not permitted. This is where many travellers run into problems at the checkpoint.
Source: European Commission Regulation (EU) 2015/1998 and its implementing regulations; TSA guidance under 49 CFR Part 1540; UK Department for Transport aviation security directions.
What counts as a liquid
The LAGs category covers liquids, aerosols, gels, pastes, and items of similar consistency. The operative question is not whether an item is technically a liquid at room temperature, but whether it flows or can be spread. EU Regulation 2015/1998 does not define the term exhaustively; checkpoint officers exercise discretion.
| Item | Counts as LAG? | Notes |
|---|---|---|
| Water and soft drinks | Yes | 100 ml rule applies |
| Shampoo and conditioner | Yes | 100 ml rule applies |
| Toothpaste | Yes | 100 ml rule applies; treat as a gel |
| Sunscreen and creams | Yes | 100 ml rule applies |
| Mascara and lip gloss | Yes | 100 ml rule applies |
| Contact lens solution | Yes | 100 ml rule applies (except medical quantities with documentation) |
| Jam, honey, peanut butter | Yes | TSA and EU authorities classify these as gels |
| Yoghurt, hummus | Yes | 100 ml rule applies |
| Soup in a flask | Yes | 100 ml rule applies |
| Solid bar soap | No | Solid form; no restriction |
| Solid deodorant stick | No | Solid form; no restriction |
| Powder makeup (blush, foundation) | No | Solid form; some airports screen powders separately |
| Hard cheese | No | Solid food; no restriction at security |
| Chocolate bar | No | Solid food; no restriction at security |
| Sandwiches and wraps | No | Solid food; no restriction at security |
Exceptions to the 100 ml rule
Baby food, infant formula, and breast milk in quantities reasonably needed for the duration of the flight are exempt from the 100 ml rule. Passengers must declare these items at the checkpoint. Officers may test liquids using trace detection equipment. The exemption applies in the EU (Regulation 2015/1998), UK, and US (TSA guidance).
Liquid medication in quantities exceeding 100 ml is permitted when accompanied by documentation — typically the original prescription label or a letter from a treating physician. The medication must be declared separately at the checkpoint. Rules vary by country; some airports require the prescription to match the passenger's travel documents. See the medication guide for full detail.
Insulin, glucose gels, and associated liquid diabetic supplies are exempt from the 100 ml rule with appropriate documentation. TSA advises passengers to carry documentation from a physician and to inform officers before screening begins. Insulin pens and vials must be clearly labelled.
Liquids purchased at airport duty-free shops after the security checkpoint may be carried regardless of volume if they are sealed in a Security Tamper-Evident Bag (STEB) with the receipt visible inside. However, STEB bags from one airport are not always accepted through a connecting security checkpoint at a different airport. See the duty-free sealed bags guide for details on when STEBs survive transit.
Regional variations
The 100 ml rule is consistent across the EU, UK, and US. The bag requirement is universal. However, implementation details vary:
- EU airports with CT scanners:Several EU airports have deployed computed tomography (CT) scanning equipment at security checkpoints, which can detect explosive liquids without the 100 ml restriction. Airports including Amsterdam Schiphol, London Heathrow (some lanes), and several others have been trialling the removal of the LAGs restriction for passengers screened on CT lanes. As of 2025, the EU has authorised airports to lift the restriction where CT equipment meets ECAC standards, but adoption is uneven. Check the specific airport's website before assuming the rule has been lifted.
- UK: Following its departure from the EU, the UK planned to raise the limit to 2 L at CT-equipped airports. Implementation was delayed multiple times; confirm current status with the UK Department for Transport or the specific airport.
- Australia: The Australian Government applies the 100 ml rule at all international departure checkpoints in line with ICAO guidance.
- Canada: Transport Canada applies the 100 ml / 1 L bag rule at all Canadian airports.
Common mistakes
Buying water airside, then connecting
A water bottle purchased after clearing security is not subject to the 100 ml rule at that checkpoint. However, if you connect through another airport where you must re-clear security — particularly common when connecting outside the EU — the bottle will be confiscated. This is one of the most frequent causes of confiscation at hub airports such as Dubai, Doha, and Istanbul.
Large container, small amount
A 200 ml bottle of shampoo that is half-full contains under 100 ml of liquid, but it remains prohibited. The rule applies to the container capacity, not to the volume of liquid inside it.
Toothpaste as a solid
Toothpaste is classified as a gel, not a solid. A standard 150 ml tube exceeds the 100 ml container limit and will be confiscated at most checkpoints. Travel-size tubes of 75–100 ml are compliant.
- Cabin baggage rules — full carry-on reference
- Duty-free sealed bags (STEBs) — when airside purchases survive connecting checkpoints
- Medication — liquid medication over 100 ml