# What is overbooking (of flights), and why do airlines all seem to do it?

I know that they want to "fill every seat."

If you take this LITERALLY, then you'd want to overbook, because of the statistical percentage of "no shows." That, of course, leads to "bumping" when more passengers actually show up than the statistical formulas predict.

But one could also define "fill every seat" as "sell every ticket," then there's no point in overbooking. From an economic point of view, a seat would be "filled" as soon as the ticket was sold. Whether or not the passenger showed up wouldn't be of concern, as long as the ticket was paid for. And if a passenger wanted to change flights, s/he could be charged a penalty to cover the expected loss on the replacement; the closer to flight time, the higher the penalty.

A "full" plane is a crowded plane and thus an unpleasant plane. A plane in which every ticket was sold, but there were a few "no shows" is actually nicer to ride on. It would also be easier on the plane; there would be a smaller load.

Can airlines be persuaded to change their objectives in passengers' favour, so there is no "bumping" and less crowding? Would it make sense for passengers to push airlines to adopt other solutions (such as charging 10%-20% more for tickets, to compensate for the lost "overbooking" option). Would this (or some other idea) be better than forcing passengers to buy first class tickets if they want to avoid being "bumped?"

• Tickets would be more expensive, so I'd rather travel on a full plane. You can chose to travel first class, then you don't have an unpleasant experience. – Bernhard Apr 8 '13 at 15:15
• Many LCCs do this. No changes, not for any price. It's a policy that leads to people hating the airline. It does enable them to not overbook, but since bumping is rarer than wanting to change, they tend to go back to allowing changes. – Kate Gregory Apr 8 '13 at 15:16
• The consequences of your proposed model are that if you as a passenger miss any flight for any reason at all, you are now liable for coming up instantly with the cash to continue your trip. – Peter M Apr 8 '13 at 15:50
• I voted to reopen, I was a victim of over booking once when the airlines calculated that wrong... I had to delay my flight. Luckily the airlines provided a hotel for me. I think it is nice to understand the mechanism behind it. – Nean Der Thal Apr 9 '13 at 0:54
• @HaLaBi: Not only the mechanism, but what passengers can do about it (or push for). I have improved the question by addressing these issues. – Tom Au Apr 9 '13 at 13:26

As far as i understand it, there is a system behind it; more than just assuming that a few % of the passengers just wont make it to the flight, leaving some seats empty.

Lets say the seat costs the airline $100 for the flight, and the ticket sells for$200 a few months before the flight. The closer you get to departure date, the more expensive the ticket gets - lets a ticket costs you $400 the day before departure. Now you are on the airport, they figure out they are overbooked and offer passengers a$300 voucher if they take another flight. In theory, the people who paid the least amount of money for the ticket will be more likely to accept the offer, making room for people who paid more for the seat last minute because they really need to get there. However, the Airline also makes money here, because now they have a seat sold twice (for $200 and again for$400 = $600), and buy it back for$300 and still made a $200 profit on a seat that costs them only$100 for the flight.

So essentially, they try to push the cheaper passengers out of the flight to make room for the passengers who paid more and increase the revenue per seat they will get on that flight.

• The part about the tickets getting more expensive before the flight has nothing to do with the date actually, it is the subclasses of the class. Where cheaper classes get filled and premium classes are not. Sometimes you can find the cheaper tickets hours before departure. – Nean Der Thal Sep 12 '13 at 4:28
• This kinda sorta seems to make sense but they are several things that are wrong. First, yield management and overbooking are two different things. Overbooking exists since a long time and is really about filling the aircraft to the max. Another important things is that the price per seat does not matter. You have pay the crew, maintenance and fuel in any case so even a passenger paying 5$or 10$ increases your profit (as long as it is genuinely a new passenger and it's not cannibalizing the revenue you are making on more expensive tickets). – Relaxed Sep 12 '13 at 6:14
• In your example, you could also just abstain from selling the $200 ticket, wait for the 400$ passenger and make even more profit as you don't need to cover the 100$difference between the original price and the voucher. The only reason you might in principle do something like what you describe is that you want to reduce the risk of passing on the$200 revenue and discover later than there is no $400-passenger for this flight. So it really is about not leaving some seats empty. – Relaxed Sep 12 '13 at 6:24 • This doesn't make sense: no seat is sold twice. Or, to be anal, one seat is sold twice but another one is occupied without being directly paid, since you already paid for the first (overbooked) seat. – o0'. Jul 5 '14 at 10:17 • @DJClayworth: not true. Airlines required to offer compensation (see e.g. law.cornell.edu/cfr/text/14/250.5 and airpassengerrights.eu/en/denied-boarding.html) They bank on the passengers not knowing this and try to look for volunteers that are satisfied with less cash or future flight coupons. If they do a hard bump, they need to pay. – Hilmar Oct 4 '16 at 1:08 If rebooking is allowed, then "sell every ticket" does not equate to "fill every seat", since the passenger who moves to a different flight for a small fee takes up a seat in that other flight. Rebooking is a privilege that has been around for a very long time; taking that away from passengers is going to annoy business travelers very much, so it's unlikely to happen. To compensate for the loss of revenue from empty seats they might have otherwise filled, airlines would most likely have to increase their prices, and thus become less competitive. It appears that there are too many people who don't care quite as much about personal comfort as long as the price is low to make "half-empty economy class" a viable business model. In the end of the day, airlines want to maximize profit, and if they can increase profits while alienating only a small fraction of travelers (including you, unfortunately), they'll go for it. For an experience that is similar to a half-empty economy class (but with better food), I recommend flying business class - you pay a premium, but get more space and better service. Note that maintenance rules for airplanes are set up regarding the number of hours flown, which means that the maintenance costs of an airplane are about the same whether it flies full or empty. Let's say there are 10 seats, all sold at 100 dollars. However, this flight actually costs 1050 dollars to operate. So, in order to cover their costs, they could either charge 105 dollars per seat, or do the same 100 dollars per seat, and overbook (and get another$50) , because their computers say there is a very good chance someone will miss the flight.

The airlines have years and years of data on how many people will show up and who will miss the flight for every single combination of variables - Wednesday night in El Paso in March? Sunday night in Las Vegas in August? They know who exactly who did and didn't show. And, on the other side, paying people out that they overbook, they all try to avoid the involuntary bumping requirements (which are actually a good deal for the customer) and try to make it a voluntary bump and pay you off in airline credits instead.

Running an airline is not a very profitable business, and the actual "revenue per flight" is really much lower than people think it is.

Short answer - vote with your dollars, but time has proven people only care about the price, and everything else people "say", when the chips are on the table, the lowest cost will just about always get the traveler's vote.

• Most of the time, a return ticket is much cheaper than oneway, so a bunch of people will buy a return flight they did not intend to take in the first place. – arney Jul 19 '13 at 12:50
• The cost of operating the flight is not relevant at all. Once the airline decided to fly the plane, any additional passenger is good to take (the marginal cost is very low) and you want to extract as much profit from each individual passenger as possible. The point of overbooking is making sure you sell as many tickets as possible and avoid flying with empty seats when passengers with flexible fares don't show up. – Relaxed Sep 11 '13 at 16:08
• If I had the options "100$ticket" and "105$ ticket and you will actually fly", I will choose the second one without any doubt. – Džuris Aug 6 '17 at 12:51

The main issue is that, even if your own ticket does not allow it, most airlines do offer tickets that can be canceled or rebooked at little or no surcharge and they want to be able to continue to do that. They could in principle stop offering that service and avoid any need to overbook. They could also still allow changes or cancellations and just make sure they never fully book an aircraft to reduce the risk of having to bump or reschedule some passengers.

The problem is that someone has to pay for it (the passengers who want to cancel a ticket and can't, the airline if it has to risk flying with a few empty seats, etc.) Alternatively the airline could push these costs to the customer but it would make the tickets more expensive, possibly put them at a competitive disadvantage or annoy the wrong customers.

Note that people flying low-cost or buying the cheapest non-refundable non-changeable economy class tickets are probably the most price-sensitive. Next time around, they are still going to go to the cheapest airline so there is nothing to gain by offering them a better service at a slightly higher price. I have had a few bad experiences with EasyJet but I still fly with them from time to time because they are usually much cheaper than the next airline on some destinations I want to go to (no overbooking in this case but other problems). It is profitable to overbook passengers like me on a flight to offer them a cheap ticket and fill the plane but bump them to offer some flexibility to customers paying more.

The airline's goal is to have someone pay something to offset the huge fixed costs, hence overbooking, yield management, etc. The question is who is ready to pay how much and for what and how to correctly discriminate between these different classes of customers. Airlines might be getting it wrong but they definitely looked into it and chances are that increasing the cheapest tickets' price or stopping to offer flexibility for higher class fare would mean losing some passengers.

• The low cost people who can't fly every day only buy a plane ticket if they actually need to get somewhere. I believe that most of them with explicit options of "guaranteed ticket" vs "bumpable ticket" will not hesitate to pay 5-15% more for a guaranteed flight. – Džuris Aug 6 '17 at 12:53
• @Džuris I seriously doubt it, many things suggest that people really just look at the fare and nothing else. But ultimately it doesn't necessarily matter, flexible tickets cost much more than 5-15% more as does taking the risk to fly with additional empty seats. If passengers with non-changeable tickets could not be bumped, it would make it more difficult for airlines to fill the plane or profit from premium fare. – Relaxed Aug 6 '17 at 13:05
• On the other hand, if only a proportion would be interested, a little bit like economy premium tickets for extra legroom, it would be an intriguing idea. – Relaxed Aug 6 '17 at 13:11
• If I need to fly home, it's because I my vacation is over and I have to go to work. Hell, if I could afford to fly at another time, I might have chosen another airline that has flights at that time but not at the one I needed. – Džuris Aug 6 '17 at 13:12
• @Džuris Sure but how does that matter? Vacation schedules are rarely so sensitive that you don't have many options and legacy airlines tend to treat you better when it comes to irregular operations, may have more flights to get you to your destination if something goes wrong, etc. They also (used to) be more lenient with luggage, not charge you extra to use a credit card, etc. But the fact is that we downplay everything that could go wrong and still flock to the low fares. That's an observation airlines have made time and time again and second-guessing does not change anything. – Relaxed Aug 6 '17 at 13:20

Would it make sense for passengers to push airlines to adopt other solutions (such as charging 10%-20% more for tickets, to compensate for the lost "overbooking" option)

NO!!! Very few people are ever inconvenienced by overbooking, but everybody would be massively inconvenienced every time they flew, if the tickets were 10–20% more expensive.

Alternatively, if you proved me wrong by demonstrating that people were prepared to pay 10–20% more for flights, I can tell you exactly what would happen. The airlines would say, "Thanks. We're raising ticket prices by 10–20% and, guess what? We're still overbooking you. So long, suckers!" As a real-life example, British Airways was making a loss on Concorde until market research revealed that most people thought tickets cost about twice what they actually did. BA took this as a big ol' hint that people were prepared to pay more to fly on Concorde and, bingo, it made a profit from then on.