Carry-on bags
You can bring one carry-on bag and one personal item for free on most domestic and international flights. But there are a few rules you’ll need to follow.
Size limits
Make sure your bags meet our size limits before you get to the airport. You can bring one carry-on bag and one personal item on your flight if you’re not traveling in Basic Economy.
Carry-on bags
Your carry-on bag must fit in the overhead bin, so it must be 9 in x 14 in x 22 in (23 cm x 35 cm x 56 cm). When measuring your bag, be sure to include the handle and wheels.
Personal items
These items must fit under the seat in front of you, so they must be 9 in x 10 in x 17 in (22 cm x 25 cm x 43 cm). Common things include purses, backpacks and laptop bags.
If you’re at the airport and not sure if your carry-on is the right size, you can use our bag sizers to measure your bag.
Any bags in addition to your carry-on and personal item, or carry-on bags over the size limit, will need to be checked. If you do have to check bags you may have to pay a fee.
Traveler pro tips
Small purses or bags are not allowed in addition to your personal item and carry-on. However, you can bring a few other items for free:
- Jacket or coat
- Umbrella
- Things to read
- Food or other items bought at the airport
- Mobility devices, including wheelchairs, canes, and crutches
- A car seat, child safety harness or stroller
- A diaper bag and breast pump (even if you’re not traveling with your child)
- Camera
Traveler pro tips
Small purses or bags are not allowed in addition to your personal item and carry-on. However, you can bring a few other items for free:
- Jacket or coat
- Umbrella
- Things to read
- Food or other items bought at the airport
- Mobility devices, including wheelchairs, canes, and crutches
- A car seat, child safety harness or stroller
- A diaper bag and breast pump (even if you’re not traveling with your child)
- Camera
Packing special items
Some items have a few extra rules for how they can be packed. We also always recommend checking with the TSA before packing anything you’re unsure of in your carry-on.
Smart bags
If you have a smart bag that uses lithium batteries, the batteries must be removed before they’re brought on board.
Liquid, gels and sprays
The TSA allows you to bring liquids, gels and sprays in your carry-on bag. However, the container can be no larger than 3.4 ounces (100 mL) and must be placed inside a quart-size clear, sealable bag.
Powders
The TSA recommends you place powders in your checked bags. But you can bring up to 12 ounces (350 mL) in your carry-on bag when you fly domestically in the U.S.
Musical instruments
You can bring a small instrument on your flight in a hard case. It’ll be considered your carry-on if you place it in the overhead bin, or your personal item if you place it under the seat in front of you. Learn more about musical instruments.
Medication, vapes and essentials
Always make sure you place any medication, vapes, e-cigarettes, keys and other essentials in your personal item in case your bag is gate-checked.
You can bring medical syringes on your flight as well. If you need to use your syringes during the flight, ask a flight attendant to help you dispose of them safely.
Fragile, bulky or unusual
If an item is too fragile or bulky to check, or you feel it needs to be handled with special care, you can buy a ticket for it.
Basic Economy bag limits
For most trips you can only bring one personal item when you’re flying in Basic Economy. You can’t bring a carry-on bag unless you’re flying to South America, across the Atlantic or across the Pacific. All other bags have to be checked.
If you decide to travel with a carry-on bag, you must check it before airport security for a fee starting at $35. If you bring a carry-on bag to the gate that won’t fit under the seat, you need to pay a fee starting at $65 to check it.
If you’re a MileagePlus members with Premier status, traveling with a Premier member, are the primary card member of a qualifying* MileagePlus credit card or a Star Alliance Gold member you can bring one free carry-on bag.
*The United GatewaySM Card and the United MileagePlus® Select Card do not qualify for a free carry-on bag in Basic Economy.
Gate-checked bags
Your carry-on bag might be gate-checked if a plane runs out of overhead space, your bag is over the size limit or you’re over your carry-on bag allowance.
Gate-checked bag guidelines vary depending on whether you’re flying with a United Express® carrier. To find out if you’re flying on United Express, view your trip in My Trips. In each flight segment we’ll tell you if your flight is operated by another carrier.
Bags are most frequently gate-checked on United Express flights because of the following restrictions:
- If you’re flying CommutAir, you’re only allowed one personal item.
- All other United Express carriers allow carry-on bags but have limited space.
For most United flights, gate-checked bags can be picked up at baggage claim at your final destination. However, on United Express flights, gate-checked bags may be picked up at baggage claim or on the jet bridge after arrival.