This mornign I checked out United flights SMF to IAD, and the price was $441. An hour ago it was up to $660. Any ideas why?

The cheaper fare buckets sold out or some time-sensitive condition expired.

Airline revenue/yield management classes are the first to fill up at Hogwarts.

So Hogwarts is where you go to learn those tricks? Now you tell me!

Honestly, it could be any number of reasons. I got lucky today and an airfare I was watching dropped about $50 between 8 and 5.... could have gone up without any warning too.

Delete cookies and see what price you get.

An interesting idea. All cookies, or just the ones from the UA site?

I hadn't realized Hogwarts offered bus. ad. classes, but of course there should be at least a few. Useful for Fred and George.

One of the number of reasons could be that someone bought the last $441 ticket and less than two hours later somebody canceled a $441 ticket within 24 hours of their purchase.

rephrasing that:
One of the number of reasons could be that, when you first checked, someone had already bought the last $441 ticket and less than two hour later somebody canceled a $441 ticket within 24 hours of their purchase, so you saw it available.

I have noted in the past that fares change sometime on Tuesday thru Wednesday. Sometimes if I check UA later on a Wednesday I'll see a different fare.

What happens if you delete cookies??? Now I'm curious.

Carol

Cookies allow the airline computers to flag you as a "shopper" who might "bite" if you think the fare is going to climb out of sight.

I've seen fares change 3 times the same day - usually upward, and then down again 2 days later when I signed in from a different computer.

I'm not a conspiracy-theory-junkie, but if you were an airline and you could mess with "shoppers'" minds to get them to pay more, wouldn't you?

The problem with the cookies idea.... See my post above. 8 AM fare is $250, a few hours later the same day fare is $199. Today fare is still $199.....

I don't think I buy it.

Cookies are used to track you and your searches on websites whether you "buy it" or not. That's why people delete cookies. If you return to a website and haven't deleted cookies, it remembers your previous search and can adjust accordingly.

I don't believe the major airlines raise their fares based on your history of visiting. I know for a fact that Northwest/Delta does NOT - at least not for me! I did a lot of tweaking of my upcoming flights to Europe before finally booking them. I noticed that fares often went up and down hours or days later without a clear reason. I had a suspicion that Northwest/Delta and their partners may have been tweaking the fares at regular intervals for various routes and that could have affected my results in unexpected ways.

Just because you checked a fare last night and then two hours later checked it again and it was higher and then cleared cookies the next morning and it went back down doesn't mean clearing the cookies was the factor, any more than the sun coming up that morning was.

Many, many, many other reasons why fares can and do bounce around, but wanted to explain the thinking behind clearing cookies. It happens much too often that a fare found while shopping rises within hours or even minutes not to suspect at least a little manipulation from one or another airline, esp. on less traveled routes. But each airline has a different set of marketing policies and practices. They just LOOK like they collude.

I've done a LOT of fare searches on united.com (I buy almost all our tickets through that site)--including multiple searches for the same itinerary within a short period of time. While the site definitely leaves cookies, I can't say that I've ever suspected that they are being used to adjust the fares I see. I also look at the fare classes available and can usually attribute any differences to new fares that have become available, lower fares that were in limited quantity and now sold out--that sort of thing. That said, I do delete the cookies occasionally, but certainly not in between every search.