The laws on how to travel with liquids has changed a few times over the years with the increase in terrorist attacks in airports and on airplanes. It’s worth pointing out that these rules are based on travel in the European Union, but I do know that USA and most of Asia, have very similar rules.
Amount of liquids allowed on an airplane
In a single, transparent, resealable plastic bag, insert your liquids. Make sure each item is not be more than 100ml, which holds no more than a litre and measures approximately 20cm x 20cm. It’s important to know that the bag must not be knotted or tied at the top and you’re limited to only one plastic bag per person.
Examples of permitted liquids
To give you an idea liquids include: cosmetics and toiletries, including creams, lotions, oils, perfumes, mascara and lip gloss. Sprays, including shaving foam, hairspray and spray deodorants. Pastes, including toothpaste, gels, including hair and shower gel and contact lens solution.
Exceptions for flying with liquids
There are some exceptions, and you can take liquid containers larger than 100ml through security if they: are for essential medical purposes, are for special dietary requirements or contain baby food or baby milk.
You can also take liquids bought at an airport or on a plane (such as duty free) through security if the items are sealed inside a security bag when you buy them, the receipt for the items is sealed in the security bag and visible.
Be organised prior to going through airport security
Store your liquids bag at the top of your suitcase or backpack so that you can get access to it easily. Please make sure you follow the rules and get out your liquids as you are queuing up for airport security. The number people that hold up others moving through security because they are not prepared, or, even have liquids packed all over their back is down right annoying.
The UK Government has a comprehensive section on how to travel with liquids with only carry on luggage, if you are looking for more information on this topic.