How Many Ounces of Liquid Can You Take on a Plane?

By Shelley Hoose

Making your TSA experience a smooth one

How Many Ounces of Liquid can you Take on a Plane?

You've been planning that fabulous trip to Costa Rica for months and you certainly don't want to get waylaid at the security line because your carry-on bag includes – egad! – a prohibitively large shampoo bottle or that gift of wine for your host. Get the TSA restrictions down and pack smart from the start ... then just relax and start dreaming of your first swim at Playa Grande.

The 3-1-1 liquids rule

The Transportation Security Administration implements what it calls the 3-1-1- rule, restricting the amount of liquid allowed in a carry-on. Here's the gist:

  • 3.4 ounce containers
  • 1 quart-size clear plastic resealable bag
  • 1 bag allowed per traveler

So, grab just one quart-size plastic bag and fill it with any liquid-based, must-have toiletry items, making sure that each item is no more than 3.4 ounces (100 milliliters). By liquid-based, the TSA means any liquids, aerosols (yes, you can bring that small travel-sized deodorant you bought), gels, creams and pastes. Think not only shampoo, conditioner, creams and lotions, but also gel deodorant, nail polish and eye drops.

Tip

While there is no limit to the number of items you can put into your clear plastic quart-size bag, don't pack it too tightly because TSA officials may need to peek inside to verify container size. Put anything that exceeds the 3.4-ounce limit into your checked luggage in its own zip bag to avoid leakage.

Exceptions to the 3-1-1 rule

Medications and baby-care items, such as formula or juice for use during the flight, are exceptions to the 3-1-1 rule. You don't need to place these in a bag, but be sure to alert TSA officials at the checkpoint that you have medically necessary liquid items that exceed 3.4 ounces. Make sure that the contents for each item are clearly labeled so screening goes smoothly.

Carry-on items: allowed and prohibited

In addition to adhering to the 3-1-1- rule for liquids, be sure your carry-on bag contains only allowed items.

Allowed carry-on items:

  • scissors with blades less than 4 inches, wrapped or sheathed; tweezers; nail clippers; and nail files
  • safety razors
  • corkscrews
  • nail polish and polish remover
  • aerosol personal care items only (no aerosols allowed in checked bag)
  • dry batteries that power small devices, such as AA, AAA, D or D
  • e-cigarettes or vaping devices (not allowed in checked bag)
  • lighters (for checked bag only pack lighters with no fuel)
  • safety matches, but not the strike-anywhere type
  • insect repellent, but not animal repellent
  • medical mercury thermometer (only one and in a protective case)
  • duty-free perfume and cologne in any amount purchased at airport duty-free shops and clearly factory sealed

Warning

Be aware that TSA officials can, on a case-by-case basis, prohibit any item. Be conservative in what you carry on in order to avoid additional screening or the risk of having items confiscated.

Restricted items:

The TSA does not allow carrying on certain sharp objects, and the FAA prohibits flying with anything deemed a hazardous material when transported by air, whether or not it adheres to the 3-1-1 rule. These include:

  • scissors with blades that exceed 4 inches and other sharp objects
  • knives, except plastic or round-bladed
  • razor blades not in a cartridge
  • non-toiletry aerosol and liquid articles, such as laundry starch, spray paint and insecticides
  • self-defense spray

If you are unsure about an item, search the TSA website's comprehensive list of allowed or restricted items. For additional questions about potentially hazardous substances, contact the Pipeline Hazardous Material Safety Administration at 1-800-467-4922.

About the Author

Lynne Pettus has worked in the communications field for more than 20 years, most recently as a technical writer and editor in the software industry. She has a Bachelor of Arts in journalism from USC.