Travelers have long been accustomed to packing liquids in their carry-on bags according to the TSA liquid limit, also known as the 3-1-1 rule.
Created by explosive experts after a thwarted plot to explode planes flying from the UK to the US, the international guideline requires airline passengers to pack their liquids inside 3.4-ounce containers—or 100 mL as most international products are marked—into one clear, quart-size bag.
While we commonly refer to these regulated substances as “liquids,” they are technically known as LAGs, an abbreviation for liquids, aerosols, and gels. This category of items also encompasses cream or pastes, or as one agent recently told me, “anything that can be passed through with a butter knife.” So in addition to common travel necessities like shampoo, face wash, and sunscreen, the TSA liquid limit rule also applies to toothpaste, hairspray, and even peanut butter. Larger liquids can still be brought along on your travels, but those items must be packed in checked luggage.
In the future, as more airports become equipped with advanced scanners that allow officers to use 3-D imaging to detect hazardous liquids, the liquid limit rule could be scrapped entirely. European airports had initially planned to eliminate their carry-on restrictions in 2024, but the timeline has been pushed back indefinitely due to technological issues.
Here in the US, the TSA tells Condé Nast Traveler they “anticipate the limit on liquids will be lifted in the coming years.” For now, the TSA liquid limit remains in effect, though recent reports say they may not be lifted until 2040. (A TSA official hasn’t responded to our request for comment.)
That means no matter where you're traveling, it's best to avoid packing liquids over 100 mL into your carry-on bag. However, there are exceptions to every rule.
Case in point: A few years ago, while roaming through Johannesburg’s Tambo International Airport, I became enamored by the selection of South African sauces at the duty-free shop. One by one, I picked them up, but sadly they were each over the 100mL liquid limit, so I put them back on the shelf. As I walked past the cashier, I expressed my disappointment.
She then kindly informed me of an exception I was unaware of at the time—that I could take the oversized liquids on board my flight, as long as I didn’t break the seal on the special bag she’d pack them in for me. Relieved, I went on a shopping spree, bringing back Ukava Africa Safari BBQ sauce and Mrs. H.S. Ball’s original recipe chutney, among a bag full of saucy souvenirs.
That’s when I learned about the inbound international flights duty-free liquids exception, designed specifically for last-minute airport purchases like this. There are a handful of other oversized liquids that TSA allows travelers to pack in their carry-on bags. However, “the final decision rests with the TSA officer on whether an item is allowed through the checkpoint,” the government agency says on its site.
For example, during the height of Zika, I tried explaining to the officer that I needed more bug spray since I’m prone to mosquito bites, but she made me toss it. But on a recent trip to Fiji, where dengue fever is an issue, I was allowed to bring through with an extra bottle, which offered peace of mind throughout the journey.
Below, see the 11 most common full-size liquids that you can actually take through airport security in the US, according to the TSA. In order to transport these approved oversized liquids, travelers should inform the security officer of the items before the screening and place them in a separate bin or dish. Anything that triggers the alarm while going through security is subject to further inspection.
Prescription liquids, gels, and aerosols
Medication that has been prescribed specifically for you is perhaps the most common item that qualifies as an exception. TSA recommends that it’s clearly labeled so there's no question about what is inside.
Depending on the situation, medication may be screened visually or with an x-ray machine. It may also be tested for traces of explosives. In some situations where the officers aren’t able to properly screen the item, you may be asked to open the container for a vapor analysis, per the TSA site.
In cases where you would like to make sure the medication isn’t opened or X-rayed, simply inform the TSA officer. “Additional steps will be taken to clear the liquid, and you or the traveling guardian will undergo additional screening procedures, which may include AIT screening, a pat-down, and screening of your carry-on property,” the site says.
Note that prescription wet pet food does not count as an exception to the TSA liquid rule, even for service animals.
Liquid medications and contact lens solution
In general, liquid medications that are not prescriptions and contact lens solutions are limited to 3.4 ounces, but TSA does allow “larger amounts of medically necessary liquids, gels, and aerosols in reasonable quantities for your trip,” with the caveat you must declare them to security officers first.
Breast milk and infant formula
Passengers traveling with infants have enough to worry about on their flights—and being able to provide the little ones with the proper nourishment should not be one of those concerns. Technically, TSA categorizes breast milk and baby formula as “medically necessary liquids.” The child doesn’t need to be present for the exception.
In order to expedite the process, TSA suggests—but doesn't require—that the liquids be transported in clear and translucent bottles, so that they can be screened by the Bottle Liquid Scanners. (Those in pouches may not be able to.) While there is a chance you may be asked to open them, nothing will ever be placed in the liquid. The agency also adds that the screening process shouldn't affect the formula, but if you prefer they not be x-rayed, alternative testing means can be requested.
While baby powder is not a liquid, note that powder-like substances that are more than 12 ounces do need to be placed in a separate bin for screening.
Baby and toddler food and drinks
In addition to breast milk and formula, food and drinks for babies and toddlers are also allowed, including puree pouches. They also technically fall into the “medically necessary” category. Water for babies is also allowed in “reasonable quantities.” They just need to be removed and screened separately from other belongings.
Liquid teethers
TSA also recognizes how important teethers are to babies and has “liquid-filled teethers” specifically called out as an item that can be brought through the security check.
Freezer packs and ice
Gel ice and freezer packs are permitted, as long as they are frozen solid when they pass through security. In fact, ice (including frozen water bottles) can also slip by. In all cases, any portion that’s been partially melted and slushy, or any liquid that is at the bottom of the container, will count toward the 3-1-1 limit.
One exception is medically-necessary gel ice packs in “reasonable qualities,” even if they are melted or slushy. That pertains with or without the presence of breast milk, the TSA specifies. Additionally, IV bags, pumps, syringes, or other accessories to medical supplies are also allowed.
Fresh eggs
Spare your eggs the pressure of being crammed into a 3-1-1-approved bag. Even with liquid yolks, they can be taken through security, but may need to be separated from the carry-on bag for proper inspection to make sure the X-ray machines show that they’re genuinely what they're cracked up to be. The TSA suggested packing them separately and keeping them “uncluttered” ahead of time to avoid any hold ups.
Live fish and coral in water
Assuming your live fish needs more than 3.4 ounces of water to survive, this is another exception to the rule, as long as they’re in a clear transparent container and properly inspected by the TSA officer. Live coral in water is also an exception. Certain airlines will also permit live lobster in a clear, plastic, spill-proof container, but we suggest checking with them first, in order to avoid making a splash.
Biological specimens
Liquid exceptions can be made in the name of science. Non-infectious specimens in preservative solution, which can include formaldehyde, ethanol, isopropanol, or other alcohols, can be carried through if it’s for scientific research. But they’ll need to be very specifically packed.
There can be up to 30 milliliters of free liquid in a heat-sealed inner plastic bag and then no more than one liter in the outer packaging, which needs to be marked: "Scientific research specimens, 49 CFR 173.4b applies." (Specific instructions for the regulation are here.)
Non-spillable wet batteries
Certain portable electronic devices may need non-spillable batteries with absorbed electrolyte, like a gel cell, absorbed glass mat, and the like. As long as the equipment is protected against accidental activation or evolution of heat, and the battery's voltage is 12 volts or less with less than 100 watt hours, then it makes it cut.
Duty-free purchased items in officially sealed bags on international flights
These days, so many international airports lead you through a massive duty-free shop en route to the departure gates, tempting you with both local products and international brands. Whether it’s Canadian maple syrup, French wine, or South African sauces (guilty!), those final chances to buy local LAG goods can be tempting. Go ahead and splurge and rest easy.
Those liquid souvenirs can be taken home, as long as they are properly sealed by the cashier in a security tamper-evident bag (STEB), and remain untampered with. The global system was developed in 2008 “to allow an exemption" to liquid volume rules for items purchased at duty-free airport retailers or on board an aircraft, according to the International Civil Aviation Organization. For US travelers, this is limited to inbound international flights, according to the TSA.
This story has been updated with new information since its original publication date.
