If there is one TSA rule that trips up more travelers than any other, it is the 3-1-1 liquids rule. It sounds simple, but the edge cases — peanut butter, mascara, snow globes, frozen meals, baby formula — are where most travelers slow down the line, get a bag inspection, or have a favorite item tossed into the bin at the checkpoint.
This is the complete guide. Memorize the basics, learn the exceptions, and you will never lose another bottle of sunscreen to TSA again.
What Is the TSA 3-1-1 Rule?
The 3-1-1 rule is the limit on liquids, gels, creams, pastes, and aerosols you can bring through airport security in a carry-on bag. The numbers stand for:
- 3.4 — every liquid container must be 3.4 ounces (100 milliliters) or less
- 1 — all your containers must fit inside one quart-sized clear, resealable bag
- 1 — you get one bag per passenger (yes, even kids, with some exceptions)
That’s it. If your liquid item is over 3.4 oz, it goes in your checked bag. If you do not have a checked bag, it goes in the trash at the checkpoint.
The 3.4 oz limit is per container, not per item
The most common misunderstanding: travelers think they can bring 3.4 oz of shampoo total. You can actually bring multiple 3.4 oz bottles — as many as fit in your quart-size bag. So three 3-oz bottles of different shampoos? Fine. One 6-oz bottle that is half-full? Not fine. The label on the container is what TSA reads, not how much liquid is inside.
What size bag counts as “quart-size”?
A quart-size resealable bag is roughly 7 inches by 8 inches (about 18 cm by 20 cm). Standard “sandwich bags” are usually too small. Look for bags labeled “quart” or “1 qt.” Most grocery stores sell them next to the freezer bags.
What Counts as a Liquid?
This is where it gets tricky. TSA’s definition of a liquid is broader than what most people expect. If you can pour it, pump it, spray it, spread it, or squeeze it, it is a liquid in TSA’s eyes.
Common items that ARE liquids (3-1-1 applies)
- Toiletries: shampoo, conditioner, body wash, lotion, sunscreen, toothpaste, mouthwash, deodorant (gel/spray, NOT solid stick), shaving cream, hair gel, hairspray
- Cosmetics: liquid foundation, concealer, mascara, lip gloss, liquid eyeliner, nail polish, perfume, cologne
- Food and drink: yogurt, hummus, peanut butter, jelly, jam, salsa, soup, sauce, gravy, honey, maple syrup, oils, vinegar, salad dressing, dips, spreads, soft cheese, pudding, applesauce, cream cheese, guacamole
- Other: contact lens solution, hand sanitizer, lip balm in pot form (sticks are fine), snow globes, gel ice packs (must be fully frozen — see below)
Items that are NOT liquids (no 3-1-1 limit)
- Solid foods: sandwiches, bread, chips, candy, granola bars, nuts, fruit, vegetables, hard cheese, jerky, baked goods
- Powders: protein powder, dry shampoo (powder form), powder makeup, baby powder. These do not count against your quart bag, though containers over 12 oz get separate powder screening
- Sticks and solids: deodorant stick, lip balm stick, solid perfume, sunscreen stick, solid bar soap
- Wipes: baby wipes, makeup wipes, disinfecting wipes
- Frozen items: anything that is completely frozen solid when you reach the checkpoint. The moment it starts to melt, it counts as a liquid.
The frozen-item rule catches a lot of travelers off guard. If you bring a frozen meal or ice pack and it has thawed even partially by the time you hit security, TSA will treat it as a liquid and apply the 3-1-1 rule.
Exemptions: Liquids Over 3.4 oz You Can Still Bring
Several categories are exempt from 3-1-1 because they are considered medically necessary or essential. You can bring “reasonable quantities” of these items in any size container, but you must declare them at the checkpoint for separate inspection.
Medically necessary liquids
- Prescription medications (liquid form)
- Over-the-counter liquid medications (cough syrup, eye drops, contact lens solution)
- IV bags, saline solution, gel packs for medical use
- Liquid nutritional supplements with a doctor’s note
You don’t need the prescription label, but it speeds things up. Tell the TSA agent before you load your bag onto the X-ray belt. For more, see our flying with medication guide.
Baby and toddler items
- Breast milk, formula, and toddler drinks (water, juice) — any quantity, even if you are not traveling with the baby that day
- Baby food, purees, and snacks in liquid or gel form
- Ice packs and freezer packs to keep the above cold
Declare these at the checkpoint. TSA will typically test them with a vapor strip or open one container — they will not have you taste it. For the full family playbook, see flying with kids through TSA.
Other exempt items
- Live fish in water (yes, really — in a clear bag or container)
- Fresh eggs
- Biological specimens (preserved samples) for academic or medical purposes
What Happens If You Forget?
If you arrive at the checkpoint with an oversized liquid, you have three options:
- Toss it — TSA will provide a bin to throw it away. This is by far the most common outcome.
- Take it back to your car or check it — only realistic if you have a lot of time and a checked bag option. Most airports do not have post-security drop-off; you’d have to leave the secure area, recheck, and re-clear security.
- Mail it home — a few major airports (LAX, JFK, MCO) have mailing kiosks before security, but they are pricey and slow.
In practice: if it is over 3.4 oz and not exempt, plan to throw it out. Don’t bring expensive liquids you can’t afford to lose.
Pro Tips to Move Faster Through the Liquids Check
The 3-1-1 rule is the #1 reason standard-line travelers get pulled aside for a bag inspection. Make it a non-event:
Before you leave home
- Buy travel-size everything. Most pharmacies sell 3 oz versions of common toiletries.
- Use silicone travel bottles ($10–15 for a set) to refill your favorite full-size products into compliant containers.
- Decant carefully: a 3.4-oz bottle filled to the brim might still get flagged if the label reads bigger.
- Pack the quart bag at the very top of your carry-on so you can grab it in one motion.
At the checkpoint
- Pull the quart bag out before the bin so you don’t fumble at the conveyor.
- TSA PreCheck travelers do NOT need to remove the liquids bag from the carry-on — it stays in. This is one of the biggest PreCheck time savings. See TSA PreCheck vs Global Entry if you don’t have it yet.
- Declare exempt items (medication, baby formula, breast milk) verbally before your bag goes on the belt.
After security
- Buy water past security, not before — bringing a sealed water bottle in is one of the most common 3-1-1 mistakes. Bring an empty reusable bottle and fill it at a water fountain after the checkpoint.
Liquids in Checked Bags
Most liquid limits do not apply to checked bags. You can pack a full-size shampoo, bottle of wine, or jar of peanut butter no problem. Exceptions worth knowing:
- Aerosols: limited to 18 oz (500 ml) per container and 70 oz total in checked bags
- Alcohol: under 24% ABV (most beer, wine) — unlimited; 24%–70% ABV (most spirits) — 5 liters per passenger in unopened retail packaging; over 70% ABV — not allowed at all. For the full breakdown including duty-free, packing for breakage, and connecting flights, see our guide on flying with alcohol through TSA
- Lighter fluid, fuel, paint thinner: never allowed in any bag
- Liquid bleach, ammonia: never allowed in any bag
International Travel: 3-1-1 Around the World
The 3-1-1 rule is a US TSA standard, but most countries follow nearly identical rules — usually written as “100 ml liquids, 1 quart bag.” Notable variations:
- EU and UK: Same 100 ml / 1 liter clear bag rule. The UK had been rolling out machines that would have lifted the liquids limit, but the rollout has stalled — assume 100 ml at all UK airports through 2026.
- Australia, Canada, New Zealand: Same 100 ml limit
- Japan, South Korea: Same 100 ml limit, but very strict about exemptions — bring a doctor’s note for any medically necessary liquids
- Domestic flights within Israel, Australia (some routes): No liquids restriction
When in doubt, follow the 3-1-1 rule and you will be fine almost everywhere.
Frequently Asked Questions
Why is it called the 3-1-1 rule?
3.4 oz container limit, 1 quart-size bag, 1 bag per passenger. The “3” was originally for “3 oz” before TSA standardized to 3.4 oz to match the international 100 ml standard, but the name stuck.
Did the TSA liquids rule change in 2026?
No. As of October 2026 the limit is still 3.4 ounces (100 mL) per container in one quart-size bag. In July 2025 Homeland Security Secretary Kristi Noem said liquids could be the next big announcement, which started the “liquids rule scrapped” stories, but no nationwide change followed. At some checkpoints with CT scanners you may be told to leave liquids in your bag, and the size limit still applies. The changes that did happen are in the new TSA rules for 2026.
Can I bring a sealed water bottle through TSA?
No. Even sealed, store-bought water is over 3.4 oz and not exempt. Empty your bottle before security and refill it after.
Does the 3-1-1 rule apply to TSA PreCheck?
Yes — the same 3.4 oz / quart bag / one-per-passenger rule applies. The PreCheck benefit is that you don’t have to remove the liquids bag from your carry-on at the checkpoint. The contents and limits are the same.
Can I bring a full-size stick deodorant?
Yes. Stick deodorant, solid antiperspirant, and powder forms are not considered liquids. Only gel and spray deodorants count toward 3-1-1.
Is mascara a liquid for TSA?
Yes. Mascara, liquid foundation, lip gloss, and nail polish all count as liquids and must be 3.4 oz or less and fit in your quart bag. Powder makeup and lipstick (stick form) do not count, which is why switching to powder products is the easiest way to free up quart bag space.
Can I bring peanut butter through TSA?
Peanut butter counts as a liquid because it is spreadable. Either bring a 3.4 oz container or pack it in checked baggage. Single-serve PB packets under 3.4 oz are fine.
What about hand sanitizer?
TSA permanently allows up to 12 oz (350 ml) of liquid hand sanitizer per passenger as a leftover from the COVID-era rules — but it must be in a separate container, declared at the checkpoint, and X-rayed separately. For all other liquids, the 3.4 oz limit still applies.
Can I bring an empty reusable water bottle?
Yes — empty bottles have no restriction. This is the smart play: bring an empty bottle and fill it at a water fountain past security.
What if I have prescription liquid medication over 3.4 oz?
Allowed in reasonable quantities. Declare it at the checkpoint. You don’t need the prescription label, though having it speeds things along. The TSA agent may test the liquid with a vapor strip but will not open it in most cases.
Are food items like yogurt or applesauce really liquids?
Yes. TSA considers anything pourable, spreadable, or pumpable a liquid. Yogurt, applesauce, hummus, jam, and soup all count. Pack them in your quart bag if under 3.4 oz, or check them. For the full breakdown of solid vs liquid foods, see our guide to bringing food through TSA.
Can my kid bring their juice box through security?
If your child is 2 or under, juice for them is exempt — any size, declare at the checkpoint. For older kids, the standard 3-1-1 rule applies, so a 6.75 oz juice box won’t make it. Buy juice past security.
Skip the surprises at the checkpoint. Before you leave for the airport, look up your airport on Airport TSA Times to see when its checkpoints are busiest, from TSA’s own hourly counts. The smartest way to plan your trip is knowing what you are walking into.