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The TSA 3-1-1 rule has been unchanged since 2006, yet it remains one of the most common reasons travelers lose items at the checkpoint. Here is exactly what the rule requires, what it exempts, and how to pack so nothing gets confiscated.
What the 3-1-1 rule actually says
Three numbers define the rule: 3.4 oz per container, 1 quart-sized clear zip bag, 1 bag per passenger. It applies to liquids, gels, aerosols, creams, and pastes in your carry-on. If it can be poured, sprayed, spread, pumped, or spilled, TSA classifies it as a liquid.
That classification is broader than most people expect. Toothpaste, shampoo, conditioner, sunscreen, deodorant (gel or spray), mascara, lip gloss, and hair spray all count. So does peanut butter, hummus, honey, and most condiments. A 12 oz jar of peanut butter is treated as a liquid and will be confiscated at the checkpoint if it exceeds 3.4 oz.
The quart bag holds roughly 7 to 8 standard 3 oz travel bottles before it stops closing cleanly. If your full toiletry lineup exceeds that, something has to be decanted into a smaller bottle, purchased at your destination, or checked.
What is exempt from the 3.4 oz limit
Several categories travel outside the quart bag with no size restriction:
Medications. Both prescription and over-the-counter liquid medications are exempt. Declare them separately to a TSA officer at the checkpoint. Keeping them in original or labeled packaging speeds up screening. You do not need a prescription card or doctor's note, but labeling helps.
Baby and toddler items. Liquid formula, breast milk, toddler drinks, and baby food pouches are fully exempt. A child does not need to be present for breast milk to qualify. Ice packs and gel packs used to keep formula or breast milk cold are also allowed through.
Solid-format toiletries. These are not subject to the rule at all. Shampoo bars, conditioner bars, stick deodorant, stick sunscreen, lipstick, and powder makeup have no carry-on size limit. They take up zero quart-bag space and are worth switching to if you travel frequently.
Solid-format toiletries bypass the 3-1-1 rule entirely. A shampoo bar, stick sunscreen, and stick deodorant leave your quart bag free for everything that has to be liquid.
How to pack your quart bag without losing anything
Packing your carry-on toiletries
Take stock before you pack
List every liquid, gel, and aerosol you normally bring. Toothpaste, face wash, moisturizer, sunscreen, deodorant, shampoo, conditioner. Write them out before you reach for your toiletry bag.
Switch solids where you can
Shampoo bars, conditioner bars, solid cologne, stick sunscreen, and stick deodorant take zero quart-bag space. Even swapping two or three items to solid format opens up meaningful room.
Decant, do not squeeze
Transfer liquids into labeled refillable travel bottles of 3 oz or less. Do not bring the full-size bottle and assume it will pass because it feels mostly empty. The limit is the container size on the label, not the amount remaining.
Check the container label, not the fill level
A 12 oz lotion bottle with 2 oz left is still a 12 oz container. It will be confiscated. A 3 oz bottle filled to the top will pass.
Lay the quart bag flat in your carry-on
Keep it near the top or in an external pocket so you can pull it out quickly for screening at airports without CT scanners. You will not need to remove it at CT-scanner checkpoints, but those vary by airport.
Declare exemptions separately
If you are carrying medications or baby items over 3.4 oz, take them out before you reach the X-ray belt and let the TSA officer know. Do not tuck them inside the quart bag.
CT scanners: a process change, not a rule change
As of May 2026, 255 U.S. airports have deployed CT (computed tomography) scanners. At these checkpoints, you may be able to leave liquids and electronics inside your bag during screening rather than removing them for a separate bin. This is a checkpoint-process improvement, not a change to the 3.4 oz or quart-bag rules. The limit still applies regardless of the scanner type.
If you travel through a major hub regularly, check whether your home airport has CT scanners. The TSA website maintains a list, though checkpoint operations can vary by terminal and lane even within the same airport.
Common mistakes that lead to confiscation
The checkpoint is not a negotiation. Oversized liquids are confiscated on the spot. TSA officers cannot hold items for later retrieval. The only safe moves are to transfer to a compliant travel bottle before you leave home, buy at your destination, or check the bag.
The mistakes that come up most often:
- Bringing a full-size sunscreen or lotion and assuming "it is mostly empty" will be good enough
- Packing peanut butter, nut butter, hummus, or jam as a snack without accounting for the liquid classification
- Forgetting to remove the quart bag from a carry-on before the X-ray conveyor at airports that do not have CT scanners
- Using a sandwich bag instead of a proper quart-sized bag, which causes screening slowdowns even if the contents are compliant
- Putting medications inside the quart bag instead of declaring them separately, which can slow down secondary screening
Choosing the right bag for the checkpoint
A well-organized toiletry bag like the BAGSMART Hanging Toiletry Bag makes the quart-bag step faster, not slower. Your quart zip bag should be easy to access without unpacking your whole carry-on. For a broader look at what works for different trip lengths and bag setups, see our guide to the best toiletry bags.
Can I bring a full-size shampoo bottle if it is mostly empty?
No. The limit applies to the container size printed on the label, not the amount of liquid remaining. A 12 oz bottle with 2 oz left is still a 12 oz container and will be confiscated. Decant into a travel bottle of 3.4 oz or less before you leave home.
Do I need to declare my medications at the TSA checkpoint?
If your liquid medications exceed 3.4 oz, you are required to notify a TSA officer at the checkpoint. Both prescription and over-the-counter liquid medications qualify for the exemption. Keeping them in original or labeled packaging speeds up the process. There is no documentation requirement, but labeling helps.
What is the easiest way to reduce quart-bag space?
Switch to solid formats where possible: shampoo bars, conditioner bars, solid cologne, stick sunscreen, and stick deodorant are all TSA-exempt and take up zero quart-bag space. For items that must stay liquid, use a set of refillable travel bottles (3 oz or less each) filled from your full-size bottles at home. That approach gives you full control over what fits and keeps the quart bag from becoming a last-minute scramble at the checkpoint.
For more on packing light and choosing gear that moves through security without friction, browse our travel gear guides or read how we research and rate products.
Recommended gear
Our current top picks from the Best toiletry bags for travel in 2026 guide, if you are ready to buy.

BAGSMART
BAGSMART Hanging Toiletry Bag
- Folded dimensions (medium)
- 10.8 x 3.5 x 7.9 in
- Open span
- 11 x 30 in
- Material
- Water-resistant polyester with padded shell
- Hook
- 360-degree swivel metal hook
- Compartments
- 4 zippered interior sections plus back open pocket
- Transparency
- Clear panels on main compartments
The BAGSMART hanging toiletry bag is Amazon's top-ranked option in the category, with more than 63,000 ratings at 4.8 stars. It unfolds flat for counter use or hangs from a door, towel bar, or shower rod via a swivel hook, keeping full-size bottles accessible without consuming counter space.

VORSPACK
Vorspack Canvas Hanging Toiletry Bag
- Dimensions
- 10 x 5.5 x 5 in
- Material
- Water-resistant canvas with PU leather trim
- Hook
- Reinforced leather handle and hang loop
- Interior pockets
- 3 mesh pockets plus 1 long zippered mesh pocket
- Front pocket
- 1 exterior zippered pocket
- Bottom
- Reinforced for shape retention
Vorspack's canvas hanging bag earns 4.7 stars from more than 11,000 Amazon reviewers at a price well under $20. The canvas exterior gives it a classic dopp-kit look, while the internal mesh and zippered pockets handle a typical grooming kit without fuss.

OSPREY
Osprey Ultralight Zip Organizer
- Dimensions
- 5.5H x 9.1W x 3.1D in
- Weight
- 4.2 oz empty
- Material
- Lightweight nylon with hang loop
- Capacity
- 2 liters
- Mirror
- Included compact mirror
- Warranty
- Osprey All Mighty Guarantee (lifetime repair or replace)
Osprey's Ultralight Zip Organizer weighs 4.2 oz and packs flat, making it a strong option for carry-on-only travelers who refuse to check a bag. At 2 liters it keeps a travel-size kit organized across 5 compartments, and it ships with a small mirror. Osprey's lifetime guarantee backs the build quality.




