What the airlines actually allow
The amount of luggage you can bring depends on which airline you fly with and what type of ticket you bought. Most major U.S. carriers — American, Delta, United, Southwest — allow one carry-on bag and one personal item (like a purse or laptop bag) at no extra cost. For checked luggage, the rules split: economy passengers on most airlines get one free checked bag; premium economy or business class passengers get two or more.
The catch is that "one free checked bag" does not mean unlimited weight or size. Standard dimensions are roughly 62 inches when you add length plus width plus height, and the weight limit is usually 50 pounds. Go over either limit and you pay a fee — typically $35 to $100 for the first overage bag, depending on the airline and route.
Budget airlines like Spirit and Frontier charge for everything: a carry-on bag costs extra, and a checked bag costs extra. Southwest is the exception among major carriers — two checked bags fly free on any ticket type, which is why it appeals to people who travel with a lot of luggage.
Key Takeaways
- One carry-on bag and one personal item are free on every major airline; checked bags depend on your ticket type and airline.
- A standard checked bag is 62 inches (length + width + height) and 50 pounds; oversized or overweight bags trigger fees of $35 to $100.
- Budget airlines charge separately for carry-on and checked bags, so read your airline's baggage policy before you book.
- Southwest allows two free checked bags on any ticket, making it the cheapest option if you need to check multiple bags.
- Carry-on bags must fit in the overhead bin or under the seat in front of you; if it does not fit, the gate agent will check it for free.
Carry-on bag rules and what fits
Your carry-on bag rides with you in the cabin. The size limit is typically 22 inches long by 14 inches wide by 9 inches deep, though airlines phrase this differently — some say "22 x 14 x 9" and others say "must fit in the overhead bin." The practical test is whether it slides into the sizer frame at the gate; if it does, you are fine.
A personal item — wallet, phone, small backpack, laptop bag — has no official size limit on most airlines. It just has to fit under the seat in front of you. People routinely bring a full-size laptop backpack as a personal item without issue.
The one hard rule: if your carry-on is too big for the overhead bin, the gate agent will check it for free. You do not pay a fee. This happens often on full flights, and the airline absorbs the cost. So if you are unsure whether your bag will fit, you can bring it to the gate and let the agent decide.
Checked bag fees and weight limits
Your first checked bag is free on most airlines if you have an economy ticket. The second checked bag costs $35 to $45 on most carriers. A third bag costs more, and most airlines cap you at two or three checked bags per passenger anyway.
Weight matters. The standard limit is 50 pounds per bag. If your bag weighs 51 to 70 pounds, you pay an overweight fee (usually $100). Above 70 pounds, most airlines will not take the bag at all — they consider it a safety hazard for ground crews to handle.
Dimensions also count. If your bag is larger than 62 inches (length + width + height), it is oversized and costs extra — usually $100 to $200. A standard rolling suitcase is about 29 + 21 + 14 = 64 inches, so it is right at the edge. Measure before you pack if you have a large bag.
How to measure your luggage correctly
Pull out a tape measure and measure the length, width, and height of your bag at its widest points. For a rolling suitcase, measure from the bottom to the top of the handle, the widest part of the bag side to side, and the deepest part front to back. Add all three numbers together.
For weight, use a bathroom scale or a kitchen scale. Weigh yourself, then weigh yourself holding the bag, and subtract. If you do not have a scale at home, most shipping stores (UPS, FedEx, USPS) will weigh a bag for free or for a dollar or two.
Write down the dimensions and weight and keep them handy. If you fly the same route regularly with the same bag, you only have to measure once.
Baggage rules for different ticket types
Economy tickets come with one free checked bag on most airlines. Some discount economy fares (called "basic economy" or "economy saver") on American, United, and Delta do not include a checked bag — you have to pay $35 to $45 to check one. Always check your ticket confirmation email to see what is included.
Premium economy and business class passengers get two free checked bags, sometimes three. First-class passengers on some airlines get even more. If you are flying premium, your baggage allowance is usually printed on your ticket or in your airline account.
Frequent flyer elite members (like American Airlines Gold or Delta Silver) earn extra checked bags as a benefit. If you are a member, log into your airline account to see what you get.
What happens if you exceed your baggage limit
If your checked bag is overweight or oversized, you pay the fee at the counter when you check in. The agent will weigh and measure your bag, tell you the fee, and you pay by card or cash. Most airlines charge $100 for an oversized bag and $100 for a bag over 70 pounds.
If you bring a second checked bag and your ticket does not include it, you pay $35 to $45 at check-in. There is no way around it — you cannot pay online after you book, only at the airport.
If your carry-on is too large, the gate agent will check it for free. You do not pay. If the flight is full and there is no overhead bin space, your bag goes in the cargo hold anyway, and you get it back at baggage claim.
Tips to avoid baggage fees
Pack light. A carry-on bag and a personal item are always free, so if you can fit everything into those two bags, you pay nothing. Most people can travel for a week with just a carry-on and a backpack.
Choose your airline based on baggage policy. If you need to check two bags, Southwest is cheaper than Delta or United because both bags are free. If you are a frequent flyer, check whether your elite status gives you free checked bags.
Weigh your bag before you leave home. If it is close to 50 pounds, remove a few items. It is easier to repack at home than to pay $100 at the airport.
Book your baggage allowance online if your airline offers it. Some carriers let you buy a second checked bag in advance for $25 to $30, cheaper than the $35 to $45 you pay at the airport. Check your airline's website after you book.
Frequently Asked Questions
Can I bring a carry-on bag and a personal item on every flight?
Yes. Every major airline allows one carry-on bag and one personal item at no cost. Budget airlines like Spirit and Frontier charge for a carry-on bag, so check your airline's policy when you book. The personal item (backpack, purse, laptop bag) is always free.
What if my suitcase is 1 inch over the size limit?
If it does not fit in the sizer frame at the gate, the agent will check it for free. Airlines are flexible about carry-on size because they know the sizer is approximate. If it fits in the overhead bin, you are fine. If it does not, you do not pay — it just goes in the cargo hold.
Do I have to pay for a second checked bag if I am flying with a child?
Yes, unless your airline or ticket type includes it. Children do not get free extra baggage on most airlines. Each passenger — adult or child — gets the same baggage allowance based on their ticket type. Check your airline's policy for any family travel discounts.
Can I bring a full-size rolling suitcase as a carry-on?
Most full-size rolling suitcases are 62 to 64 inches (length + width + height), which is over the typical 62-inch carry-on limit. They often fit in the overhead bin anyway because the sizer frame is approximate. If it does not fit, the gate agent will check it for free. Bring it to the gate and let them decide.
What if my bag weighs exactly 50 pounds?
You are fine. The limit is 50 pounds, so 50 pounds is within the limit. If it weighs 50.1 pounds, some airlines will round down and let it through; others will charge the overweight fee. Weigh at home and aim for 48 to 49 pounds to be safe.