Checked luggage is baggage you hand to the airline at check-in that rides in the aircraft cargo hold, while carry-on stays in the cabin with you.
Hand your bag to the agent and you won’t see it again until the carousel. The two categories follow different size rules, fees, and security limits, and mixing them up leads to a $25 surprise at the gate or a favorite tool left at the checkpoint.
Checked Luggage, Defined
Checked luggage is baggage the airline accepts, screens, and stores in the cargo hold for the flight. You drop it at the check-in counter or bag-drop station and have no access to it until you collect it at baggage claim. Because it travels out of reach, checked baggage is where bulky and restricted items go — full-size toiletries, most tools, and anything the TSA won’t let through the checkpoint.
Carry-on, Defined
A carry-on is the bag you bring into the cabin yourself, fitting under the seat in front of you or in the overhead bin. It stays with you the whole trip, which is why people pack laptops, medications, and valuables in it. Carry-ons are bound by the airline’s size and weight limits and the TSA’s screening rules. A bag can meet the airline’s dimensions and still get flagged at the checkpoint for a prohibited item.
Size, Weight, And Fee Rules
Checked bags commonly run up to 50 pounds and 62 linear inches, though every airline sets its own numbers.
American Airlines lists its checked-bag allowance at 62 inches (158 cm) and 50 lbs (23 kg) for most regions. First and Business passengers may get up to 70 lbs (32 kg), and bags on Australia or New Zealand routes can also run 70 lbs (32 kg).
Fees add up fast.
| Feature | Checked Luggage | Carry-on |
|---|---|---|
| Where it rides | Cargo hold, out of reach | Cabin, with you |
| Typical size cap | 62 linear inches | 45 linear inches (FAA) |
| Typical weight cap | 50 lbs (23 kg) | Varies; often no scale |
| Liquids | Full-size bottles OK | 3.4 oz (100 ml) per container |
| Tools | Power tools, anything over 7 in | Tools 7 in or shorter |
| Lithium batteries | Only if batteries removed | Preferred for battery gear |
| Cost | Usually a fee per bag | Usually free |
Security Rules, Batteries, And What You Can’t Check
The TSA’s screening rules and the FAA’s PackSafe list draw a hard line between the two bag types. Most dangerous goods are forbidden in both, with narrow exceptions for some personal items.
Liquids are the classic split. Carry-on containers are capped at 3.4 ounces (100 milliliters) each, all fitting in one quart-size resealable bag; anything larger belongs in a checked bag. Tools follow the same logic:
Lithium batteries are the biggest exception. FAA PackSafe says baggage equipped with lithium batteries has to travel as carry-on unless the batteries are removed first. Many spare lithium batteries are carry-on only, so a checked bag is the wrong home for a power bank or spare camera battery.
If you’re narrowing down which bag to buy, our tested roundup of the best checked luggage for air travel breaks down the models worth the fee.
Mistakes That Cost You At The Counter
- Assuming every airline shares one size or weight limit. They don’t, and the FAA notes an airline can require some or all bags to be checked anyway.
- Packing a restricted item in the wrong bag. TSA and the FAA both expect item-by-item checking before you fly.
- Forgetting that checked bags can be opened. TSA may inspect a checked bag and leave an inspection notice inside.
- Carrying oversized liquids to the checkpoint instead of packing them in the hold.
Gate-checking a carry-on changes your access to the bag and can trigger that extra fee, so build size and weight into your plan before you leave home.
FAQs
Can I put lithium batteries in my checked bag?
Generally no. FAA PackSafe guidance says baggage equipped with lithium batteries must be carried as carry-on unless the batteries are removed first, and many spare lithium batteries are carry-on only. Pack power banks and loose camera batteries in your cabin bag.
What size bag counts as checked luggage?
Most airlines cap checked bags at 62 linear inches and 50 pounds, though American Airlines allows up to 70 pounds for First and Business or on Australia and New Zealand routes. Anything larger than 45 linear inches typically needs to be checked rather than carried on.
Can I bring full-size toiletries in a carry-on?
No. Carry-on liquids are limited to 3.4 ounces (100 milliliters) per container, all fitting in one quart-size resealable bag. Anything larger has to go in your checked luggage, where full-size bottles are allowed.
References & Sources
- Transportation Security Administration. “What Can I Bring?” Item-by-item screening rules for carry-on and checked baggage, including the 7-inch tool limit and liquid caps.
- Federal Aviation Administration. “Baggage” FAA PackSafe guidance on dangerous goods, lithium batteries, and the 45 linear inch carry-on benchmark.
- American Airlines. “Checked Baggage Policy.” Current size, weight, and fee figures for checked bags, including the 62 in / 50 lb standard and gate-check surcharge.