It seems like every few months, someone comes up with the latest and greatest formula for when to book flights.  Do you book early, or wait to the last minute?  Other than booking 43.784 days in advance, rounded to the nearest lunar eclipse, while standing on one leg in pajamas with feet on them (having feet on them is the critical part), I can’t give much of a guarantee on the lifelong question.

But I did recently notice a trend while planning a trip, and I thought I’d share.

The Story

I needed to book a trip to Atlanta, and had found flights that would work for me.  There were a number of different times during the day, all at the same price – $313 roundtrip.  Morning, afternoon, and evening flights were all available at $313.  Then, one day, the price for the flights I wanted – and for all the other flights – jumped up about $100 to $414.  It wasn’t just the evening flights I was looking at; all flights during the day increased in price.

When I saw that, I knew a little about what that meant.  On any given flight, there are a certain number of tickets available at various prices.  There are a certain number, say 10, at the cheapest price, then maybe 10 more at a slightly higher price, 10 more at a slightly higher price, and so on.  The different price categories are called “fare classes” (or sometimes, “fare buckets”).  The word “buckets” may sound strange, but it makes sense: when all the tickets in a certain “bucket” are taken, you have to move on to the next (higher priced) bucket.

Fare Buckets

If you’ve ever seen Kayak or other sites tell you “Only 1 seat left at this price,” believe it or not, they’re actually not lying and trying to trick you into booking:

They really are reporting how many tickets are left in that “fare bucket” and the next fare bucket is almost always going to be more expensive.  If you see this message, there’s a good chance that the price of that particular flight really is going to go up soon (if 2 more people book).

In the case of the Atlanta flights I was looking at, however, it wasn’t a situation where just the specific flight I wanted had gone up in price.  In other words, it wasn’t the fact that the ticket was coming from a higher fare bucket.  Rather, it was a situation where Delta decided to raise prices across the board for all flights.  Overall, airfare pricing and economics is rather complicated, and often doesn’t make much sense (but in the end, it really just comes down to supply and demand)…but when I saw this increase as being across the board (other flights went up the exact same amount), I figured that it was one of 2 things:

1. The original price I had seen was a temporary sale, and once that sale ended, fares went back up to their “normal” price.  Or…
2. Delta decided to raise its prices temporarily in an effort to make some more money on ticket sales for a period of time.  If/when they decided that the prices had been high for long enough (maybe they weren’t selling any tickets), they would bring the prices back down.

If it was Case 1, I figured I didn’t have much to lose by waiting a few more days.  Of course, the prices could have continued to rise…and this is often the case with flights that are getting closer and closer to departure.  Typically, this will occur at 21, 14, and 7 days out.  But for my flights, I was still about a month out from departure, so I decided to wait a few days.  Based on typical fares that I’ve seen, $400 is a bit high, so I figured that wasn’t going to be the “going rate” and that the $300 prices weren’t a temporary sale.

Sure enough, after a few days, prices came right back down to where they started.  At that point, I jumped on it, and booked the exact flights I wanted.  Of course, they could decide tomorrow that they’re going to drop prices across the board to $200, but that’s the way it goes!

The Moral of the Story: When to Book Flights

So overall, if you’re looking at a trip, keep an eye on prices of other flights (on the same day, just at different times).  If you see prices go up across the board (again, only compare on the same day), it’s probably one of the 2 situations I described above.  If the situation ends up being #2, it may be worth waiting a few days to see if prices come back down.  But if the specific flight you’re looking at is the only one that goes up in price, it’s very unlikely that it will come back down (because the cheaper fare buckets are now “empty” and your ticket now has to come from a more expensive fare bucket).

Hopefully this helps a little in deciding when to book flights and when to wait it out if the price increases.  Feel free to post a comment below if you have further questions!