What exactly is the purpose of checking in for a passenger flight?

Thread title pretty much says it. Obviously the airline needs to know who, and how many, of the people who are booked on a particular flight actually show up for it - not just for security reasons but also for things as mundane as overbooking and seeing if you need to put any passengers on other flights. But today’s check-in doesn’t ensure that - with all these online check-in and mobile check-in and whatnot options, which you can do a day or so before departure, it’s perfectly possible that someone checks in for a flight and yet doesn’t show up. I can also see that you have to do something with your luggage if you want to check it, but that doesn’t explain why people who travel with hand luggage only have to undergo a checking-in process.

To me, checking in is just an annoying extra process that you have to perform before you fly; I agree it’s not overly annoying, but on the other hand I don’t see the added value that it creates, so it could just as well be skipped: When you book a flight, you are given (either physically or electronically, with a barcode to print out) a ticket which simultaneously serves as your boarding pass. So what’s the purpose of having your passengers go through a procedure which doesn’t seem to amount to anything more than “Yes, I am booked on that flight, as you know, and I really want to take that plane?”

My personal theory is that it’s just a leftover from the time when you’d check in by personally reporting to a desk, so the procedure ensured that you were actually physically at the airport prior to departure. But is there an added value of it in today’s world as well?

Certainly it helps to know a little bit in advance of the end of the boarding process that you aren’t going to show up so they can give your seat away to standby passengers. If you could just show up at the last second of boarding and get on, they couldn’t do that.

But if you’ve checked in on line and have only carry on baggage they don’t know that, which is the point. You could still show up at the last minute. Giving your seat to standby passengers depends whether or not you are physically present at the gate, not whether or not you checked in.

Right, it sets a deadline. I believe for Southwest, for example, they have a 10-minute (?) rule by which if you are not checked in they can remove you from the manifest, which either eliminates an overbooking or allows a standby passenger your seat.

ETA: It looks like for American you have to be checked in 30 minutes prior to departure to guarantee a seat: http://www.aa.com/i18n/travelInformation/checkingIn/arrivalTimes.jsp?anchorLocation=DirectURL&title=arrivaltimes

Checked in, or at the gate?

For Southwest, according to their website, it is both.

I believe typically what they do is run a list of names that bought a ticket but didn’t check in. Then they call them out over the intercom to see if they showed up but just forgot to check in (although I don’t see how you can get through security that way - maybe it’s just cya).

Without a check-in requirement I don’t see how they could enforce their 10-minute rule and start kicking folks off the flight.

I think also, that if miss your flight without having even checked in, the airlines will generally be at least somewhat accommodating – try to get you on a later flight or something. But if you check in and then don’t show, you’re SOL. Your seat flew, and you weren’t in it.

I’m pretty sure the names they call on the intercom are for people who have checked in but have not boarded.

If you haven’t checked in, they don’t try to find you.

It is possible to have a reservation on a flight without being ticketed for the flight, especially when your flight involves multiple airlines.

If you go browse the flyertalk.com forums sometime, you will see all kinds of tales of woe of people who booked complex multi-airline itineraries and then made some sort of change to their itinerary and the airline that issued the ticket didn’t push an electronic ticket (or the proper type of ticket) to the airline that would be operating the flight or didn’t properly cancel a segment in the other carrier’s reservation system which caused the traveler to be registered as a no-show which caused the other airline to cancel the remainder of the itinerary.

The airlines have a complex accounting system. When you have a multi-airline itinerary, one airline collects the money and issues the tickets and then electronically pushes a ticket to the other airlines and sends their reservation system an update message. When you actually show up, the airline operating the flight then “collects” the ticket and sends it to a clearing house to be reimbursed from the airline that issued the ticket. If they don’t have a proper ticket, they don’t get paid.

Yes, in the era of (almost) all electronic ticketing, they still electronically emulate the procedures of paper ticketing. An airline collects a coupon (paper or electronic) which it has to redeem to get paid.

The check-in step issues you a boarding pass (not a ticket). If all works as expected, then at this point if your itinerary is not properly ticketed, you should be denied a boarding pass. Better to find this out in advance than to show up at the gate with 10 minutes left until doors close and be told your paperwork is not in order.

Here is an example. In this case, an airline took over a reservation from a travel agency in order to make a change at a passenger’s request. They apparently changed a segment being operated by another airline but did not properly reissue the ticket to the operating airline. And the operating airline even issued a boarding pass under the assumption that the passenger had a paper ticket. (Everything did not work as expected.)

Most airlines give away seats in two rounds: first people who haven’t checked in by some deadline (like 30 minutes before departure), then for people not at the gate a little later (like 15 minutes). Maybe that makes things go a little quicker if they can clear some of the passengers earlier.

It also helps to ID bodies if you know exactly who was or was not actually on the plane.

Not to be overly cheerful or anything.

What if I show up with a ticket issued in another person’s name? Assuming that I would be allowed aboard, they would never know who blob #28 was. Don’t think bodies of airplane crashes get open casket services, they can’t even be embalmed.

I’ve had a reservation (and seat assignment) for a flight, and shown up with carry on luggage only. I went through security, and hung out at the gate. But that doesn’t tell the airline that I’m there.

They called my name to make sure I was actually present.
Now, I make it a point to check in with the gate agent, just to let them check the box in the system.

Well, it helps to know who sat where when it comes time to figure out in what order the crash survivors will succumb to bizarre and fatal accidents.

Interesting. How’d you get through security without a boarding pass?

I have only ever flown international. Sometimes I have bought my ticket three months ahead to get a cheap price, and I assume that the check-in process is a final confirmation that I still intend to fly.

Unless I’m flying standby, I’ve never bothered the gate people. I’ve got my boarding pass, dealt with TSA; when they call my number I get on the plane. Never been a problem for me.

I believe the OP’s point is that this requirement is perfectly satisfied by the boarding pass scan when one physically boards. Surely that’s a more reliable listing of passengers than who checked in, since check-in may be done remotely up to 24 hours in advance.

When I fly Southwest, I print my boarding pass at home the day before. Unless I check bags, they have no idea if I am going to show up until I hand in my boarding pass when I get on the plane.

Same here. If I check in on line, that gives the airline the indication that I at least have the intention to take the flight the next day. However, it doesn’t provide any guarantee that I will actually make it to the airport in time for the flight. I could oversleep or be caught in traffic and never get there. If I only have carry-on, I just need to show a boarding pass to get through security but the agents do no more than look at it and as far as I know that information is not passed on to the airline. The airline has no real confirmation as to whether I will be on the flight until my boarding pass is scanned.

As Troutman suggests, perhaps the main function these days is to prioritize giving seats to standby passengers: non-check-ins first, then no shows at the gate.

I recently was able to board a connecting flight to New York in Miami when I arrived at the gate only 5 minutes before they closed the doors. (My flight from Panama had been delayed so I had less than an hour to get through immigration, customs, recheck my bag, and then run across half the terminal to get to my gate.) I don’t know whether they didn’t have enough standbys to need to give away my seat, or if having been on the connecting flight was enough so they held it in case I arrived. I suspect the former.

You wouldn’t get through security, let alone be allowed on board. You need to have a boarding pass with a name matching that on your photo ID to get through security.

Matching exactly. Last year I was awarded special treatment by TSA because my fucking middle name was misspelled (Steven instead of Stephen). When I rolled my eyes I was informed that they didn’t have to let me fly.

(Flight was booked by an employee and I foolishly never double checked)