Can You Bring Liquids, Batteries & More in a Carry-On? TSA Rules Explained

Navigating TSA regulations can feel like decoding a complex puzzle, especially when you're rushing to catch a flight. One minute you're confidently packing your favorite full-size shampoo, and the next, you're surrendering it at security. We've all been there—watching helplessly as TSA agents toss our expensive skincare products into the bin of forgotten toiletries.

Understanding what you can and cannot bring in your carry-on isn't just about avoiding embarrassment at the checkpoint. It's about traveling smarter, saving money, and breezzing through security with confidence. Whether you're a seasoned business traveler or planning your first international adventure, this comprehensive guide will demystify TSA rules for liquids, batteries, electronics, and all those "gray area" items that leave travelers scratching their heads.

Let's dive into everything you need to know to pack like a pro and sail through airport security without a hitch.

The 3-1-1 Liquids Rule: Breaking Down the Basics

The TSA's 3-1-1 rule is perhaps the most well-known (and frequently violated) regulation in air travel. Despite its widespread familiarity, confusion still reigns at security checkpoints nationwide. Let's break it down clearly:

What Is the 3-1-1 Rule?

The rule is actually quite simple when you understand what each number represents:

• 3: Each liquid container must be 3.4 ounces (100 milliliters) or less
• 1: All containers must fit in ONE quart-sized, clear, plastic, zip-top bag
• 1: Each passenger is limited to ONE bag of liquids

This rule applies to all liquids, gels, aerosols, creams, and pastes. The key word here is "container size"—it doesn't matter if your bottle is only half full. If the container itself holds more than 3.4 ounces, it's not allowed.

What Counts as a Liquid?

Here's where travelers often get tripped up. The TSA definition of "liquid" is broader than you might think:

Common liquids that must follow the 3-1-1 rule:

• Shampoo, conditioner, and hair gel
• Toothpaste and mouthwash
• Makeup including mascara, liquid foundation, and lip gloss
• Hand sanitizer and hand lotion
• Contact lens solution
• Deodorant (gel or aerosol types)
• Peanut butter, jam, and other spreadables
• Beverages (though you can buy these after security)
• Perfume and cologne

Pro tip: Solid stick deodorants are not subject to the liquids rule, making them an excellent space-saving alternative for carry-on travelers.

Exceptions to the Liquids Rule

Not everything liquid must follow the 3-1-1 rule. Important exceptions include:

• Medications (liquid, gel, or aerosol) in reasonable quantities for your trip
• Baby formula, breast milk, and juice for infants or toddlers traveling with you
• Liquid prescription medications with a matching name on the prescription label
• Medically necessary liquids such as liquid nutrition or protein supplements

These items should be declared at the security checkpoint and will undergo additional screening. Keep them easily accessible in your carry-on.

Battery Safety: What You Need to Know

Batteries have become one of the most regulated items in air travel, and for good reason—lithium batteries pose a fire risk in aircraft cargo holds. Understanding battery rules is crucial for modern travelers who pack everything from laptops to electric toothbrushes.

Lithium-Ion Batteries: The Main Event

Most of your electronic devices—smartphones, laptops, cameras, and power banks—use lithium-ion batteries. Here's what you need to know:

Batteries under 100 watt-hours (Wh):

• Allowed in carry-on luggage without restrictions
• Devices with installed batteries can go in checked baggage (though not recommended)
• Spare batteries MUST be in carry-on only
• Cover terminals to prevent short-circuiting (use original packaging, tape over contacts, or place in separate plastic bags)

Batteries between 100-160 watt-hours:

• Allowed in carry-on with airline approval
• Limited to two spare batteries per passenger
• Common in professional camera equipment and some laptops

Batteries over 160 watt-hours:

• Prohibited on passenger aircraft
• Must be shipped as cargo with proper documentation

How to Calculate Watt-Hours

If your battery doesn't list watt-hours, you can calculate it: Watt-hours (Wh) = Voltage (V) × Amp-hours (Ah)

For example: A battery rated at 3.7V and 5,000mAh (5Ah) = 3.7 × 5 = 18.5 Wh

Power Banks and Portable Chargers

Power banks have become essential travel companions, but they come with specific rules:

• MUST be in carry-on luggage (never in checked bags)
• Must be for personal use
• Capacity should be under 100Wh (about 27,000mAh)
• Airlines may limit the number you can bring (typically 2-3)
• Should be in your personal item for easy access during screening

Other Battery Types

Alkaline batteries (AA, AAA, C, D, 9V):

• Allowed in both carry-on and checked baggage
• Spare batteries should have terminals covered
• Install in devices when possible

E-cigarettes and vaping devices:

• Allowed in carry-on ONLY
• Prohibited in checked baggage
• Cannot be used or charged on the aircraft

Electronics: Laptops, Tablets, and More

The good news? Most electronics are welcome in your carry-on, and many travelers prefer to keep valuable devices with them rather than risk damage or theft in checked luggage.

Standard Screening Procedures

At the security checkpoint, you'll need to:

• Remove laptops larger than 12 inches from your bag and place them in a separate bin
• Keep tablets, e-readers, and smartphones in your bag (unless using TSA PreCheck)
• Remove cameras and video game consoles in some cases
• Ensure all electronic devices are charged enough to power on if requested

TSA PreCheck members can leave laptops and electronics in their bags, making the screening process much faster.

Smart Luggage Considerations

If you're investing in modern luggage with built-in batteries for USB charging, pay attention to battery regulations. The best carry-on options like the Samsonite Essens Carry-On Spinner or CALPAK Hue Carry-On Luggage offer traditional designs that comply with all airline regulations. If you choose smart luggage, ensure the battery is removable—many airlines now prohibit smart luggage with non-removable batteries in both carry-on and checked baggage.

Medical Electronic Devices

Special rules apply to:

• CPAP machines (don't count toward carry-on limits)
• Insulin pumps and diabetic supplies
• Portable oxygen concentrators (must be FAA-approved)
• Other medical electronic devices

These should be declared at screening and may require documentation from your healthcare provider.

Food and Snacks: What Can You Pack?

Bringing your own food is a smart way to save money and accommodate dietary restrictions, but TSA rules can be surprisingly strict about what's allowed.

Solid Foods: Generally Allowed

Pack these without worry:

• Sandwiches and wraps (keep them solid—no excessive sauces)
• Fresh fruits and vegetables (note: some international destinations have agricultural restrictions)
• Solid cheese and hard-boiled eggs
• Cookies, crackers, and chips
• Chocolate and candy
• Granola and protein bars
• Nuts and trail mix

Liquid and Spreadable Foods: Subject to 3-1-1

These items must follow the liquids rule:

• Peanut butter, Nutella, and other spreads
• Jams, jellies, and preserves
• Yogurt and pudding
• Hummus and dips
• Canned foods
• Soups and sauces
• Salad dressings

Insider tip: Pack spreadable foods in your checked baggage, or buy single-serve packets (under 3.4 oz) if you must have them in your carry-on.

Ice and Ice Packs

• Frozen ice packs are allowed if completely frozen solid at screening
• Partially melted ice packs are subject to the liquids rule
• Regular ice is allowed if frozen solid
• Dry ice is permitted in limited quantities (up to 5.5 pounds) with airline approval

Personal Care Items: Beyond the Basics

Understanding what counts as a liquid versus a solid can save you precious space in that quart-sized bag.

Items NOT Subject to Liquids Rule

• Solid deodorant sticks
• Bar soap
• Solid perfumes
• Powder makeup (eyeshadow, blush, powder foundation)
• Solid shampoo and conditioner bars
• Makeup wipes and facial cleansing cloths

Items Subject to Liquids Rule

• Roll-on and gel deodorants
• Liquid or cream makeup
• Hair styling products (mousse, gel, spray)
• Sunscreen and aloe vera gel
• Moisturizers and serums

Space-saving strategy: Switch to solid alternatives whenever possible. Solid deodorants, shampoo bars, and powder products can significantly reduce the number of items competing for space in your liquids bag.

Medications and Medical Supplies

The TSA makes reasonable accommodations for medical necessities, but proper preparation ensures smooth screening.

Prescription Medications

• Allowed in any amount necessary for your trip
• Can be liquid, gel, or solid form
• Should be labeled with prescription information
• Keep in original containers when possible
• Declare at the checkpoint for inspection

Over-the-Counter Medications

• Pills and tablets have no restrictions
• Liquid medications follow special medical liquid rules (not subject to 3-1-1 if declared)
• Bring documentation for large quantities if possible

Medical Equipment

• Syringes and needles are allowed with accompanying medication
• Insulin and diabetes supplies are permitted
• EpiPens and similar injectors are allowed
• Medical marijuana products remain federally prohibited at airports

Pro tip: Carry a letter from your doctor explaining medical necessities, especially for injectable medications or medical devices. While not required, it can expedite screening.

Sharp Objects and Tools: The Gray Area

This category creates the most confusion because rules depend on blade length, tool type, and TSA officer discretion.

Prohibited Sharp Objects

Never pack these in carry-on:

• Box cutters and utility knives
• Ice picks
• Meat cleavers
• Razor blades not in cartridges
• Swords and sabers
• Throwing stars

Allowed Sharp Objects (with restrictions)

• Safety razors (cartridge razors are fine; disposable razors are fine; straight razors are prohibited)
• Tweezers and nail clippers
• Disposable razors
• Scissors with blades shorter than 4 inches from the pivot point
• Knitting needles (check with your specific airline)
• Crochet hooks

Tools and Hardware

Small tools are generally permitted:

• Screwdrivers shorter than 7 inches
• Wrenches and pliers shorter than 7 inches
• Small hammers
• Standard-sized hand tools

However, anything that could be used as a weapon is subject to TSA officer discretion.

Size and Weight Restrictions for Carry-On Luggage

While we're focused on what goes inside your carry-on, it's equally important to ensure your bag itself meets airline requirements.

Standard Carry-On Dimensions

Most airlines follow similar guidelines:

• Typical maximum: 22" × 14" × 9" (length × width × depth)
• International flights may have stricter limits: 21.5" × 15.5" × 9" is common
• Personal items: Usually 18" × 14" × 8" or smaller

Important: Dimensions often include wheels and handles, so check total exterior measurements. Our size checker tool can help you verify if your luggage meets specific airline requirements.

Recommended Carry-On Options

When choosing reliable carry-on luggage that complies with most airline policies, consider these options:

For frequent travelers, the Travelpro Platinum® Elite International Carry-On Spinner at 21.75" × 15.75" × 7.75" offers maximum packing capacity while meeting international size restrictions. Its slimmer depth makes it ideal for overhead bin placement.

Those seeking lightweight options might prefer the Eagle Creek Expanse 2-Wheel 21.5" International Carry-On Luggage at just 5.25 lbs, which provides ample packing space without adding unnecessary weight.

For business travelers who prioritize organization, the Carl Friedrik The Carry-on Hybrid combines sophisticated design with practical dimensions (22" × 14.3" × 9") that work across most airlines.

Budget-conscious travelers can find excellent value in the Sherpani Meridian 22" Carry-On at $170, offering reliable functionality without breaking the bank.

Weight Restrictions

Unlike checked baggage, most U.S. airlines don't enforce weight limits for carry-ons, but international carriers often do:

• Common international limits: 15-22 pounds (7-10 kg)
• Low-cost carriers may have stricter policies
• Always check your specific airline's rules

Special Items: Sports Equipment, Musical Instruments, and More

Certain items require special consideration and advance planning.

Sports Equipment

Generally prohibited in carry-on:

• Baseball bats, cricket bats, and hockey sticks
• Golf clubs
• Ski poles
• Martial arts equipment

May be allowed (check with airline):

• Small fishing tackle (no sharp hooks in carry-on)
• Bicycle pumps
• Sporting event pom-poms

Insider tip: Most sports equipment must be checked, but balls (basketball, soccer ball, football) can be carried on if properly deflated.

Musical Instruments

Musicians have special considerations:

• Small instruments can be brought as carry-on items
• Must fit in overhead bin or under the seat
• Can purchase a seat for larger instruments (contact airline in advance)
• Airlines cannot force you to check instruments valued over $800 if there's space

Baby and Child Items

Traveling with children comes with additional allowances:

• Strollers and car seats don't count toward carry-on limits (but may need to be gate-checked)
• Baby food and formula in reasonable quantities
• Breast pumps and associated cooler packs
• Diaper bags as additional personal items

Prohibited Items: What Never Goes in Carry-On

Some items are absolutely prohibited regardless of circumstances:

Weapons and explosives:

• Firearms and ammunition (must be properly declared in checked baggage)
• Explosives, flares, and fireworks
• Pepper spray and mace
• Realistic weapon replicas

Flammable items:

• Lighter fluid
• Gasoline and other fuels
• Paint and paint thinner
• Aerosol spray paint

Other prohibited items:

• Chlorine and bleach
• Compressed gas cylinders
• Self-defense items (tasers, brass knuckles)
• Strike-anywhere matches

Expert Packing Tips for Smooth Security Screening

After understanding the rules, smart packing makes all the difference:

Organization Strategies

1. Use packing cubes to keep items accessible and organized
2. Place liquids bag on top of your carry-on for easy removal
3. Wear bulky items like jackets and boots rather than packing them
4. Keep electronics easily accessible for screening
5. Use a personal item strategically for items you'll need during flight

Time-Saving Techniques

• Apply for TSA PreCheck or Global Entry for expedited screening
• Choose carry-on luggage with external laptop compartments for quick access
• Pack your liquids bag in an outside pocket
• Wear slip-on shoes for quicker removal
• Have your ID and boarding pass ready before reaching the checkpoint

Maximizing Carry-On Space

When working with limited space in options like the Tumi Voyageur Léger Compact Carry-On (16" × 14" × 8"), efficient packing becomes crucial:

• Roll clothing instead of folding
• Use compression bags for bulky items
• Fill shoes with small items
• Wear your heaviest items on the plane
• Choose versatile clothing that can be mixed and matched

International Travel Considerations

Flying internationally? Additional rules may apply:

• Check destination country restrictions on liquids and food
• Research agricultural restrictions for fruits and vegetables
• Understand customs regulations for electronics and high-value items
• Consider voltage requirements for electronic devices
• Pack any valuable or essential items in carry-on (never checked)

Remember that different countries may have varying security procedures. The European Union generally follows similar liquid rules, but some countries have additional restrictions on electronics or food items.

Dealing with TSA Screening Issues

Even with perfect preparation, issues occasionally arise:

If Your Item Is Flagged

• Remain calm and cooperative
• TSA officers have final discretion on questionable items
• You can choose to return to the ticket counter and check items if needed
• Understand that some items can be mailed or shipped from the airport

Filing Claims

If TSA damages your property during screening:

• Document damage immediately with photos
• File a claim at www.tsa.gov within strict timeframes
• Keep receipts for any damaged items
• Be aware that approval is not guaranteed

Understanding Officer Discretion

TSA officers can prohibit any item they deem potentially dangerous, even if it's technically allowed. When in doubt:

• Check the official TSA website or app before packing
• Contact TSA on social media (@AskTSA) with specific questions
• Arrive early in case you need to repack or check items

Making Your Travel Experience Smoother

Understanding TSA regulations transforms from a burden into an opportunity for stress-free travel. With proper knowledge and preparation, you'll breeze through security while other passengers scramble to reorganize their belongings.

The key is preparation: research specific regulations for your items, pack strategically, and choose quality carry-on luggage that meets airline size requirements. Whether you're investing in premium options like the Bric's Life Tropea Spinner Carry On or practical choices like the Baggallini Gramercy Carry-On Duffel, ensure your luggage fits your travel style and complies with airline policies.

Conclusion: Pack Smart, Travel Confidently

Navigating TSA regulations doesn't have to be complicated. By understanding the 3-1-1 rule for liquids, battery restrictions, and prohibited items, you're already ahead of most travelers at the security checkpoint. The time you invest in learning these rules pays dividends in reduced stress, saved money, and smoother airport experiences.

Remember these key takeaways:

• Keep liquids in 3.4-ounce containers within a single quart-sized bag
• Pack spare batteries in carry-on luggage only, with terminals protected
• Declare medications and medical items at screening
• Choose solid alternatives to save space in your liquids bag
• Verify your carry-on dimensions meet airline requirements
• Arrive early your first few times to allow for any unexpected issues

Ready to upgrade your travel experience? Explore our carefully curated selection of TSA-compliant carry-on luggage, or use our size checker to ensure your current bag meets airline requirements. With the right knowledge and the right luggage, every journey starts on the right foot—or wheel.

Happy travels, and may you never again have to surrender your favorite lip gloss at security!