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Southwest Carry-On Liquids Rules 2026

Understanding TSA liquid restrictions is essential for smooth travel on Southwest Airlines. This comprehensive guide covers the 3-1-1 rule, exemptions, and exactly what you can bring in your carry-on bag.

Understanding the TSA 3-1-1 Liquid Rule

The Transportation Security Administration (TSA) enforces the 3-1-1 rule at all U.S. airports, including Southwest Airlines flights. This rule applies to all carry-on bags and personal items going through security checkpoints.

3

3.4 Ounces or Less

Each liquid container must be 3.4 oz (100ml) or smaller. Larger containers are not allowed even if partially full.

1

1 Quart-Sized Bag

All containers must fit in a single clear, quart-sized (7" x 8"), resealable plastic bag.

1

1 Bag Per Passenger

Each traveler can bring one quart-sized bag of liquids through security screening.

What Counts as a Liquid?

The TSA defines "liquids" broadly. Many items you might not expect are considered liquids, gels, or aerosols and must follow the 3-1-1 rule.

Common Liquids Subject to 3-1-1

  • • Shampoo and conditioner
  • • Toothpaste and mouthwash
  • • Liquid foundation and makeup
  • • Perfume and cologne
  • • Hand sanitizer and liquid soap
  • • Sunscreen and lotion
  • • Contact lens solution
  • • Mascara and liquid eyeliner
  • • Hair gel, mousse, and spray
  • • Deodorant (gel or spray)
  • • Nail polish and remover
  • • Lip gloss

Items That Are NOT Liquids

  • • Solid stick deodorant
  • • Solid makeup (powder, blush)
  • • Solid lipstick
  • • Bar soap
  • • Solid lotion bars
  • • Powder foundation
  • • Eyeshadow palettes
  • • Chapstick (solid)
  • • Medications in pill form
  • • Solid food items
  • • Jewelry
  • • Electronics

Exemptions to the 3-1-1 Rule

Several categories of liquids are exempt from the 3-1-1 restrictions, but they must be declared at security and may require additional screening.

Medically Necessary Liquids

Prescription medications, over-the-counter liquid medicines, and medical supplies in reasonable quantities are exempt from the 3-1-1 rule.

  • • Prescription liquid medications
  • • Insulin and diabetes supplies
  • • Liquid nutrition/dietary supplements (if medically necessary)
  • • Eye drops and saline solution (in reasonable amounts)
  • • Liquid topical medications

Tip: Inform the TSA officer at the beginning of screening if you have medically necessary liquids. You may be asked for additional screening but they will be allowed through.

Baby Formula and Breast Milk

Parents traveling with infants or young children can bring unlimited quantities of formula, breast milk, and baby food, even if the child is not traveling with you.

  • • Breast milk (any amount)
  • • Baby formula (liquid or powder)
  • • Baby food and purees
  • • Juice for toddlers
  • • Ice packs to keep items cold

Note: Inform TSA at the start of screening. These items must be removed from your bag for separate screening.

Duty-Free Liquids

Liquids purchased after passing through security or on an international flight can exceed 3.4 oz, but must remain in tamper-evident bags.

  • • Alcohol purchased in airport duty-free shops
  • • Perfume from duty-free stores
  • • Other liquids bought after security checkpoint

Important: If you have a connecting flight, duty-free liquids may be confiscated at the second security checkpoint unless they remain in sealed tamper-evident bags with receipt.

How to Pack Liquids in Your Carry-On

Step-by-Step Packing Process

  1. 1

    Get the Right Bag

    Use a clear, quart-sized (7" x 8") resealable plastic bag. Standard Ziploc quart bags work perfectly.

  2. 2

    Check Container Sizes

    Ensure each container is 3.4 oz (100ml) or less. The size marked on the container is what counts, not how full it is.

  3. 3

    Transfer to Travel Containers

    Pour full-size products into small travel bottles labeled 3.4 oz or less.

  4. 4

    Fit Everything in One Bag

    Place all liquid containers in the quart bag. It must close completely - don't overstuff it.

  5. 5

    Pack Accessible

    Keep the liquids bag at the top of your carry-on so you can quickly remove it at security.

TSA Security Screening Process

Here's what to expect when going through TSA security with liquids at Southwest airports:

At the Security Checkpoint

1️⃣

Remove liquids bag: Take your quart-sized bag out of your carry-on before placing items on the X-ray belt.

2️⃣

Place in bin: Put the liquids bag in a separate bin (not inside another bag or with other items).

3️⃣

X-ray screening: The bag goes through the X-ray machine. TSA can see the contents clearly.

4️⃣

Additional screening: If something looks suspicious, TSA may open your bag for inspection or test liquids.

5️⃣

Retrieve items: After clearing, collect your liquids bag and repack it in your carry-on.

What Happens If You Break the Rules

Violations & Consequences

  • Container over 3.4 oz: Confiscated, even if partially empty
  • Multiple quart bags: Excess bags confiscated
  • Liquids not in bag: Must dispose of items or return to check-in to check them
  • Prohibited items: Confiscated and may result in additional screening

Your Options at Security

  • Surrender items: Leave prohibited liquids with TSA
  • Return to check-in: Go back and check the bag (time permitting)
  • Mail items home: Some airports have postal services
  • Give to companion: Transfer to someone not flying

Checked Baggage vs. Carry-On for Liquids

If you need to bring full-size liquids, your best option is to pack them in checked baggage where the 3-1-1 rule doesn't apply.

AspectCarry-OnChecked Baggage
Container size limit3.4 oz (100ml)No limit (within reason)
Total liquid amount1 quart bagUnlimited
Packing requirementsClear plastic bagNo special bag required
Alcohol allowedYes (3.4 oz max per bottle)Yes (up to 140 proof, 5L total)
Aerosols allowedYes (3.4 oz max, toiletries only)Yes (toiletries and other types)

Southwest Checked Bag Option

Southwest allows two free checked bags for most passengers (A-List Preferred, Choice Extra fare, or credit card holders). This makes it easy to pack full-size toiletries without worrying about the 3-1-1 rule.

Tips for Packing Liquids Efficiently

Smart Packing Strategies

  • • Use multi-purpose products (2-in-1 shampoo/conditioner)
  • • Choose solid alternatives (bar soap, solid deodorant)
  • • Buy travel-size products instead of transferring
  • • Pack sample sizes from cosmetic stores
  • • Bring powders instead (dry shampoo, powder foundation)
  • • Buy liquids after security at airport shops
  • • Use hotel toiletries when available

Avoiding Spills & Leaks

  • • Use leak-proof travel bottles with secure caps
  • • Don't fill containers completely - leave air space
  • • Put plastic wrap over bottle openings before screwing caps
  • • Double-bag liquids in case the quart bag leaks
  • • Keep the liquids bag upright in your carry-on
  • • Check that all caps are tightly closed
  • • Use hard-case containers for creams

International Flights & Liquids

Southwest's international flights follow the same TSA 3-1-1 rules, but there are additional considerations when flying to Mexico, Central America, or the Caribbean.

International Liquid Considerations

  • • Return flights from international airports may have stricter screening
  • • Duty-free purchases must stay in sealed tamper-evident bags for connections
  • • Some countries have restrictions on importing certain liquids
  • • Customs may inspect liquids upon arrival at your destination
  • • Alcohol brought back to the U.S. may be subject to customs duties

Common Questions About Carry-On Liquids

Can I bring hand sanitizer on a Southwest flight in 2026?

Yes, but it must follow the 3-1-1 rule. Hand sanitizer containers must be 3.4 oz or less and fit in your quart-sized liquids bag. Note: During the pandemic, TSA temporarily allowed up to 12 oz, but that exemption has ended as of 2025.

What if my container says 4 oz but it's only half full?

The container size marked on the bottle is what matters, not how full it is. A 4 oz container that's only half full (2 oz of product) will still be confiscated because the container exceeds 3.4 oz. Transfer it to a smaller bottle.

Can I bring liquid makeup in my purse or does it need to be in the quart bag?

All liquids must be in the quart-sized bag, regardless of which carry-on item they're in (purse, backpack, or rolling bag). Liquid foundation, mascara, and lip gloss all count as liquids and must go in the 3-1-1 bag.

Are there any liquids completely banned from carry-on and checked bags?

Yes. Flammable liquids (gasoline, lighter fluid, paint thinner), bleach, and certain chemicals are prohibited in both carry-on and checked baggage. Consult the TSA website for a complete list of hazardous materials.

Can I bring coffee or drinks purchased before security through TSA?

No. Beverages purchased before security, including coffee, water, or soda, must be discarded before going through the checkpoint. However, you can bring empty water bottles and fill them after security, or purchase drinks in the gate area.

Do prescription liquids need to be in their original bottles?

While not required by TSA, it's highly recommended to keep prescription medications in their original pharmacy-labeled containers. This helps expedite screening and proves medical necessity if questioned. Prescription liquids are exempt from 3-1-1 limits.

Pack Smart, Travel Smooth

Following the TSA 3-1-1 rule ensures you breeze through security without delays or confiscated items. Remember: 3.4 oz containers, 1 quart bag, 1 bag per person.

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