Kayak is a travel agency and third party aggregator, so there are a couple of different ways you can book flights on Kayak. This makes the process of changing the flight you booked on Kayak different depending on how you bought it.
If You Made Your Purchase on the Kayak Site
If you made the purchase on the Kayak site itself, then you bought your flight from one of Kayak's providers. In this case, use the following instructions:
If you have your Confirmation Number or Record Locator:
If you have neither:
From there, you will be brought to a screen with the details of your flight. On that screen you can just click on the Change or Cancel buttons.
If you can't remember which credit card you used:
If You Made the Purchase Offsite
If you were redirected from Kayak's website during your purchase to an airline's website, then you actually made your purchase from the airline, not from Kayak. This happened because, if you choose a provider that is not directly affiliated with Kayak, they simply send you to them and autofill your information for you. In that case, you are going to need to contact the airline you made the purchase from directly, and follow whatever their procedure is for changing your flight.
You might not be able to make the change for free. Different airlines have different policies, and you might be subject to a change fee. In any event, you will certainly have to pay the difference in the costs of the two flights.
If Nothing Else Works
If nothing else works, then it's time to call Kayak's customer service number. You can find it here.
After thousands of Kayak customers came to GetHuman in search of an answer to this problem (and many others), we decided it was time to publish instructions. So we put together How Do I Change My Flight That I Booked on Kayak? to try to help. It takes time to get through these steps according to other users, including time spent working through each step and contacting Kayak if necessary. Best of luck and please let us know if you successfully resolve your issue with guidance from this page.
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