The security checkpoint is where the carefully packed cabin bag meets reality. A jar of homemade pickle, a bottle of hair oil, a tub of ghee for relatives abroad, or an expensive bottle of perfume bought at the duty-free: all are routinely surrendered at scanners by travellers who did not realise they counted as liquids, or who packed them in the wrong bag. None of it is complicated once you understand the handful of rules involved.
This guide sets out how the liquids rule works, what security counts as a liquid, the exemptions for medicine and baby food, the rules for power banks and batteries, and the transit trap that confiscates duty-free purchases on connecting flights. Security rules are set by each country and airport and do change, so check your departure airport and airline before you fly — but the principles below apply almost everywhere.
The liquids rule in plain terms
At most international airports, liquids in your cabin bag must be in containers of 100 millilitres or less each, and all of them must fit into a single clear, resealable plastic bag of roughly one litre, which you take out and place in the tray at screening. One such bag per passenger. The limit applies to the size of the container, not how much is in it, so a 200 ml bottle that is half empty will still be refused.
Some airports have installed newer scanners that can examine liquids inside bags, and a few have relaxed the 100 ml limit as a result. But these changes have not been uniform, and at least one country relaxed the rule and then reinstated it. The safe assumption is that the 100 ml limit applies unless your specific departure airport clearly says otherwise, and remember that the airport you fly home from, or transit through, may apply stricter rules than the one you left from.
What counts as a liquid — more than you think
Security treats as a liquid anything that can be poured, spread, squeezed, pumped or sprayed. That includes the obvious — water, drinks, perfume, shampoo — and much that travellers do not think of: toothpaste, creams, lotions, gels, mascara and lip gloss, sauces, honey, jams, soft cheeses, yoghurt, and pastes of every kind. For Gujarati travellers the everyday casualties are pickles, chutneys, ghee and oils, all of which count as liquids or pastes and are subject to the 100 ml limit in the cabin.
The practical answer is to put food items of this kind in your checked baggage, well sealed and wrapped to survive the hold, rather than in your cabin bag. Dry snacks such as thepla, khakhra, chevdo and biscuits are generally fine in the cabin. Remember too that what the airport lets you carry and what your destination allows you to bring in are separate questions: several countries, including Australia and New Zealand, restrict dairy, meat, seeds and some foods at customs, and our guide to Indian airport customs and duty-free rules covers the return journey.
The exemptions: medicine, baby food and special diets
Essential medicines, including liquid medicines and gels above 100 ml, are generally permitted in reasonable quantities for the journey, but they are not simply waved through: declare them to the security officer, keep them separate from your main liquids bag, and carry a prescription or doctor's letter. This covers insulin and other injectables, which are also exempt but should be declared — our guide to travelling with diabetes goes into this in detail, and our notes on carrying prescription medicines across borders cover the paperwork.
Baby food, formula and milk for an infant travelling with you are also usually exempt from the 100 ml limit in reasonable amounts, as are special dietary foods required for medical reasons. Again, declare them, and be prepared for them to be tested. Our guide to flying internationally with babies and infants covers the rest of what to pack for a young traveller.
The duty-free trap on connecting flights
Here is the rule that catches the most people, and it costs real money. Liquids bought at the airport shops after security — perfume, alcohol, cosmetics — are handed over in a sealed, tamper-evident bag with the receipt inside. On a direct flight that is fine. But if you connect through another airport and are re-screened there, those liquids can be confiscated if the sealed bag has been opened, if the receipt is missing, or if the transit airport simply does not accept liquids bought elsewhere.
The safest course is to leave the sealed bag unopened with the receipt visible until you reach your final destination, and if you are connecting, to consider buying duty-free on the last leg rather than the first. Our guide to long layovers and airport transit explains when you are likely to be re-screened, which is exactly when this rule bites.
Power banks, batteries and electronics
Spare lithium batteries and power banks must travel in the cabin, never in checked baggage, because a battery fire in the hold cannot be reached. Most airlines permit power banks up to a certain watt-hour rating without approval, allow larger ones only with airline approval, and ban the largest entirely. Check the rating printed on the power bank, and be aware that some airlines have gone further and now restrict using or charging power banks during the flight.
Laptops and larger electronics may need to come out of your bag at screening, depending on the scanner. Camera and drone batteries follow the same lithium rules, which our guide to camera and drone rules abroad covers. And never pack valuable electronics in checked baggage — our international baggage allowance guide explains what can go where.
Items that are simply not allowed
Beyond liquids, the standard prohibited list in the cabin covers knives and blades of any meaningful length, scissors above a small size, tools, sporting equipment such as bats and clubs, and anything flammable or hazardous, including many aerosols, lighter fluid and some self-heating food. Sharp items and tools can usually go in checked baggage instead. Religious articles are subject to specific rules that vary by country and airline, and it is worth confirming with the airline in advance rather than discovering the rule at the checkpoint.
At Indian airports, a smooth run through security starts before you reach the scanner. Our guide to DigiYatra and facial recognition at Indian airports explains how it speeds up entry and boarding, and arriving with your liquids already bagged and your electronics easy to reach saves everyone in the queue behind you a few minutes.
Frequently asked questions
Can I carry pickle or ghee in my cabin bag? Only in containers of 100 ml or less inside your liquids bag, because pastes and oils count as liquids. Larger quantities should go in checked baggage, well sealed — and check whether your destination restricts dairy or other foods at customs.
Can I take a water bottle through security? Not with water in it, above 100 ml. Take an empty bottle through and fill it airside at a water fountain or buy water after security.
Why was my duty-free perfume taken at my connecting airport? Liquids bought at an earlier airport can be confiscated at transit re-screening if the sealed bag was opened, the receipt is missing, or the transit airport does not accept them. Keep the bag sealed with the receipt until your final destination.
Do medicines count towards my liquids allowance? Essential medicines are generally exempt from the 100 ml limit in reasonable quantities, but must be declared at screening and should be accompanied by a prescription or doctor's letter.
Most checkpoint problems come down to one of a handful of rules, and knowing them turns security into a two-minute formality. When Explera Vacations books your flights, our pre-departure notes cover the security and customs rules for every airport on your route, including the transit airports where duty-free is most often lost. Ask our Surat travel desk anything before you fly through the contact page.
