Avoid Making This Pre-Flight Mistake Or You Could Lose Your Airplane Seat
Some travelers are planners. They have a packing list written out weeks before their trip, purchase travel insurance, and call every place they're staying to confirm. They get to the airport early with their flight snacks ready to go, and do everything they can to make sure the voyage is stress-free. Others tend to fly by the seat of their pants, so to speak. If you fall into the latter category, listen up. There is a pre-flight mistake you may be making that could lose you your airplane seat. If you're someone who waits to check in for their flight until you get to the airport, or does it late, you're taking a big risk. Checking in late can get you bumped from overbooked flights, and it can mess with any possible upgrades, give you a seat you don't want, or affect whether your bag arrives when you do.
Most airlines open their check-in 24 hours before a flight's departure time. If you don't bother checking in early, you're going to get a bad SEQ number on your boarding pass (the number that shows the order you checked in). While many fliers never risked checking in late with Southwest, which utilized a boarding process dependent on check-in order (a practice that ends on January 26, 2026), it's easy to get lax about it all and just wait, especially if you have TSA PreCheck, and don't have to get to the airport as early as everyone else. However, it's time to rethink that if you want your flight to run smoothly.
How you could end up getting bumped from a flight if you check in too late
Getting bumped from an overbooked flight is more likely if you're one of the last people to check in. According to the U.S. Department of Transportation, airlines are allowed to overbook their flights to compensate for people who don't show up, or if seats are required for Federal Air Marshals. They first ask for volunteers to take another flight, offering things like compensation, airline vouchers, etc. However, if no one bites, or they still have more people than seats, they can bump you. The DOT says that airlines can use things like frequent flier status and the cost of tickets as criteria for who gets to keep their seats, but if you're not high up on their platinum list or flying first or business class, they're allowed to use check-in order to choose who to bump. If your SEQ number is high, meaning you checked in late, you may be out of luck.
If you do get bumped, they have to compensate you in most cases. However, there are some situations in which they don't, meaning your late check-in can be a nightmare. For instance, if they have to switch to a smaller plane, or if there are balance or weight issues in a plane with 60 or fewer seats. Spending a few minutes to check-in when you get the reminder email, text, or app alert can mean the difference between flying and being stuck on the ground.
Other issues with checking in for your flight too late
Being bumped isn't the only danger for those who choose late check-in. If you're one of those people who like to check in at the airport, and you don't do it by a certain time, you may be denied boarding. (It's usually around 45 minutes before your departure time.) It can also affect your luggage. If you get to the check-in counter or kiosk late because of traffic, long lines, or general life drama, your checked bag may not make the cut off. Since you probably want to fly with your bag, it's worth setting an alarm for yourself to check in the first moment you can.
Seats are another issue if you have certain types of tickets. If you're flying with a basic economy fare, you likely can't pick your seats when you purchase that ticket. You're usually assigned seats at the airport. The better your SEQ number, the more likely it is that you won't get stuck in a bad seat. If you are catching an international flight some airlines may allow you to choose seats when you purchase your tickets, however, others don't until you check in, no matter what sort of economy ticket you have.
If you happen to have a seat you don't want and you're looking for a change or an upgrade, late check-in can hurt you as well. Airlines often release seats right before a flight because of cancellations, or seats that have been held for families, crew members, or passengers with disabilities. (If you're flying Delta and see an X on their seating chart, this is why.) The earlier your check-in time, the more likely you are to get what you're looking for. So, overall, it's worth a few minutes of your time to check in online early when you can.