The TSA's Basic Rules for Carry-On Items
The Transportation Security Administration (TSA) allows you to bring one carry-on bag and one personal item (like a purse or laptop bag) through security. Your carry-on must fit in the overhead bin or under the seat in front of you — most airlines use a size limit of 22 inches long, 14 inches wide, and 9 inches deep, though some budget carriers are stricter. You can pack almost anything solid in your carry-on as long as it is not on the TSA's prohibited list.
The main restriction is liquids, gels, and aerosols. These must follow the 3-1-1 rule: each container holds 3.4 ounces or less, all containers fit in one quart-sized clear plastic bag, and you pack only one bag per person. This rule exists because the TSA treats liquids as a potential security risk, not because they will spill on your clothes.
Everything else — clothes, shoes, books, electronics, toiletries in solid form — goes in your carry-on with no restrictions. You will move through security faster if you pack smart, and you avoid the risk of checked luggage being delayed or lost.
Key Takeaways
- Liquids, gels, and aerosols must follow the 3-1-1 rule: containers of 3.4 ounces or smaller, all in one quart-sized clear bag.
- Solid toiletries like deodorant sticks, solid perfume, and lip balm have no size limit and do not need to go in your liquids bag.
- Electronics including laptops, tablets, and cameras are allowed, though you will remove them at security for screening.
- Sharp objects like razors, scissors, and knives are prohibited in carry-on but allowed in checked bags.
- Your carry-on must fit the airline's size limits, which are usually 22 by 14 by 9 inches but vary by carrier.
Toiletries and Personal Care Items
Solid or semi-solid toiletries bypass the 3-1-1 rule entirely. Deodorant sticks, solid perfume, lip balm, solid shampoo bars, and toothpaste in a tube all count as solids and can be any size. Toothpaste is the exception that confuses most travelers — it is a paste, so it falls under the liquid rule and must be 3.4 ounces or smaller.
Liquids and gels that must follow 3-1-1 include shampoo, conditioner, body wash, lotion, sunscreen, liquid foundation, mascara, liquid eyeliner, and any spray (deodorant spray, hairspray, sunscreen spray). Creamy products like face cream, peanut butter, or jam are gels and must follow the rule too. Pack these in your quart-sized bag and place it in an straightforward-to-reach spot in your carry-on — you will remove it at security.
Medications in liquid or gel form (like inhalers or liquid vitamins) do not count toward your 3-1-1 limit, but you should carry a prescription label or doctor's note if possible. Solid medications like pills and vitamins have no restrictions.
Electronics and Chargers
Laptops, tablets, e-readers, cameras, and phones all go in your carry-on with no limit. You will remove your laptop and large electronics at security for X-ray screening, but they will not be confiscated. Chargers, cables, and power banks are fine — power banks must be in your carry-on, not checked, because of battery safety rules.
Larger items like hair dryers, electric shavers, and curling irons are allowed in carry-on. If your hair dryer or straightener has a lithium battery, it must stay in your carry-on for the same battery safety reason as power banks.
One note: if you are traveling internationally, some countries have different rules for electronics. Check your destination's customs rules before you pack.
Food and Drinks
Solid food — sandwiches, fruit, nuts, chocolate, cheese, crackers, cookies — is allowed in unlimited amounts. Peanut butter, hummus, yogurt, and jam are spreads and count as gels under the 3-1-1 rule, so they must be 3.4 ounces or smaller. Honey and maple syrup also count as gels.
You cannot bring liquids through security, including water, juice, soup, or any beverage. You can buy a water bottle after you clear security and fill it at a water fountain, or bring an empty bottle and fill it at the airport. Some airports have water refill stations specifically for this.
Baby food and breast milk are exceptions — they are allowed in any amount and do not follow the 3-1-1 rule, even though they are liquids.
Items You Cannot Bring in Carry-On
Sharp objects are prohibited in carry-on bags: knives (including butter knives and plastic knives with serrated edges), box cutters, razors, and scissors with blades longer than 4 inches. You can pack these in checked luggage. Lighters and lighter fluid are also prohibited in both carry-on and checked bags.
Tools longer than 7 inches or heavier than a pound are not allowed in carry-on — this includes hammers, wrenches, and crowbars. Sporting equipment like baseball bats, golf clubs, and ski poles must go in checked luggage. Firearms and ammunition are prohibited in carry-on and require special handling in checked bags (contact your airline before you pack).
Flammable items like paint, nail polish, and certain cleaning products cannot go in either carry-on or checked luggage. If you need these items at your destination, buy them there instead.
How to Pack Your Carry-On Efficiently
Place your quart-sized liquids bag where you can grab it quickly at security — the top of your carry-on or in an outside pocket. Pack heavier items like shoes and books at the bottom of your bag and lighter items on top. Roll clothes instead of folding them to save space and reduce wrinkles.
Keep your laptop and large electronics accessible so you can remove them without unpacking your entire bag. If you are traveling with a laptop, consider a carry-on with a dedicated laptop compartment. Wear your bulkiest shoes on the plane instead of packing them to save room.
Check your airline's specific size and weight limits before you pack — some budget carriers have stricter rules than full-service airlines. If your bag is close to the limit, weigh it at home on a bathroom scale. Airlines will gate-check oversized bags at no charge, but it is faster and less stressful to pack within the limit from the start.
International Travel and Carry-On Rules
The TSA's 3-1-1 rule applies to flights departing from the United States. If you are flying internationally, your destination country may have different rules. The European Union, Canada, Australia, and the United Kingdom all follow similar liquid restrictions, but the exact limits and rules vary.
If you are connecting through another country, pack accordingly for the strictest rules you will encounter. For example, if you are flying from New York to London to Paris, follow the TSA rules for your New York departure and the UK rules for your London connection.
Some countries prohibit items that the TSA allows — for example, certain types of batteries or sporting equipment. Research your destination's customs and security rules before you pack, or contact your airline's customer service.
Frequently Asked Questions
Can I bring a razor in my carry-on?
No, razors are prohibited in carry-on bags. You can pack disposable razors or electric razors in your checked luggage. If you need to shave during your trip, buy a disposable razor at your destination or pack one in checked luggage.
Is deodorant allowed in carry-on?
Solid deodorant sticks are allowed in unlimited amounts. Deodorant spray and gel deodorant must follow the 3-1-1 rule — 3.4 ounces or smaller in your liquids bag. Check your deodorant's label to see whether it is a solid, gel, or spray.
Can I bring a full-size bottle of shampoo if I pack it in checked luggage?
Yes. The 3-1-1 rule applies only to carry-on bags. You can pack full-size bottles of shampoo, lotion, sunscreen, and other liquids in your checked bag with no restrictions. Just make sure the bottles are securely closed so they do not leak on your clothes.
What counts as a gel under the 3-1-1 rule?
Gels include creamy products like face cream, peanut butter, yogurt, honey, jam, and mascara. If you are unsure whether something is a liquid or gel, assume it is and pack it in your liquids bag. The TSA may confiscate it at security if it does not fit the rule, but you will not be fined.
Can I bring an empty water bottle through security?
Yes. You can bring an empty water bottle through security and fill it at a water fountain or refill station after you clear the checkpoint. Some airports have dedicated water refill stations near the gates.