Delete your cookies!

Clearing cookies is an urban legend discounted by both Consumer Reports and National Geographic traveler. Fare differences are the result of the airline's load management software constantly tinkering with the prices. I have had fares drop 50% in just a few minutes without clearing anything.

However, deleting your cookies (and history) is a great practice for internet security (unless you like having any site you visit be able to see where else you have been.) On most browsers this requires a manual action, however Firefox can be set in preferences (at least on MACs) to delete cookies, history, and clear cache on quitting the program. Cleaning out your cache can also speed up your browser.

As for airfare prices, I have seen where offered prices were no longer available when returning to a site within a short time minutes, and after quitting and losing the data recorded on my search the original fares were immediately available when going back with a clean browser session. SNCF was particularly nasty with this. The question is, how long do they maintain your data?

I know my experience is anecdotal but I had been checking the flights for awhile and fares for two weeks and they stayed the same. I deleted my cookies and the fares on two separate airlines (Easyjet and KLM) were 20 and 25% lower.

As someone who flies often and am always searching for cheaper fares, I will try this trick next time I am about ready to book a flight.
I search with consoler daters but have always booked directly with the airlines and that has been a big help more than once while I have flown to Europe in 14 of the last 15 years.

I've checked fares a few times, before and after deleting cookies, on Orbitz, Expedia, Delta, American, and United, and not found any difference in fares or the flights they showed me. Not saying its not true, just didn't change what I was seeing in my test.

Deleting cookies may explain air fare differences on the same computer. But, can someone explain to me how my (in the suburbs) airfare is cheaper than my wife's (in the city)? Delta dropped their airfare on a flight we were interested in. Called my wife immediately. Together we looked at the same flight number for the same days and times. Her price was about $20-$22 dollars higher. She also is a frequent flier with Delta. Never could figure that one out.

Emma, as a MAC user for many years, I can tell you that on checking using a windows machine in the local library I have never seen cheaper prices than on my MAC. I am afraid that one is an urban legend.

Consumer Reports 8/2016

According to the article in Consumer reports (which was used as a source in a previous reply) there might be an effect of cookies when searching for airline fares. I'm waiting for a more scientific study or better yet a whistleblower coming forward but short of that there is some evidence that it's not an urban myth.

Emma, what you are finding is NOT because of your cookies, it is because they track your account activity at their end. For example, our (adult) kids, who do not live here, share our Amazon account, using our log-in from their off-site computers. So it can't be from cookies on their computers that I get emails directed to me for items they have looked at and set aside. Nor can this be from cookies at my end, because I delete them (and history, and cache files) every time I quit my browser to shut down. If you are logged in when you shop, rather than anonymous, they will track what you look at or set aside for later, at their end.

@Emma writes: I was once told that some companies charged people a little more if they were accessing a website from an Apple device rather than a PC, because Apple users were seen as more affluent and again prepared to pay more.

@Larry writes: Emma, as a MAC user for many years, I can tell you that on checking using a windows machine in the local library I have never seen cheaper prices than on my MAC. I am afraid that one is an urban legend.

Nope, it has been reported in the press. For example:

travel site Orbitz has been able to segment its audience in Apple and Windows camps. The upshot: Mac users will pay $20 to $30 a night more on hotels than PC users.
https://www.cnet.com/news/mac-users-pay-more-than-pc-users-says-orbitz/

And, in terms of more general price difference, there is this:

Computer science researchers from Boston's Northeastern University have proved that e-commerce sites are tracking the online shopping habits of people and will charge individuals different prices, depending on what type of device they are using to access a website.

Previous research and media investigations since 2000 have found that Amazon and US retailer Staples had been charging users different prices for products due to estimations of their wealth and geographic location, a practice known as "price discrimination".
http://www.ibtimes.co.uk/look-out-you-might-be-charged-more-if-you-shop-online-using-mac-android-device-1474431

I don't use Orbitz or Expedia, and have never had that problem. Fares with itamatrix or Googleflights were the same whether checked from home MAC or library Windows, and so they should be -since only Google could know the computer, they are the ones collecting the prices. And as I said, my kids and I get the same prices no matter which of our computers are used, and they are using different IP addresses as they don't live with me. Computer researchers have proved what they want to have proved. It is not backed up by real-world experience.

Proving something doesn't exist is difficult. Using personal experience as proof doesn't help. Discounting studies that use a large sampling of data further muddies the conversation.

Several members have posted similar experiences to mine so for now I stand by my original statement.

Richard,

I always wondered... Why are they called cookies?

Priscilla,

A quick Google...
"Computer cookies were so named by the original developer of this technology, Lou Montulli, as an homage to an earlier piece of computer monitoring technology known as "magic cookies." This earlier technology performed a function similar to modern cookies. They transmitted short code segments between machines for identification. Montulli developed the modern cookie in 1994 while working for the Internet company Netscape."

And because computer programmers like to come up with cute names for things.