Buying a plane ticket on the internet, when is my card charged?

If I pay on the web with my credit/debit card, do they charge it then, or do they charge it on the day of the flight?

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Answer:
When paying with a credit card, you’ll get charged when your bill arrives to your residence. If paying with debit, it will be charged the second you click, “Confirm”.

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Answer:
it depends in the airline company some don't charge until a week later

but they usually charge right away when your destination flight is in approach ..but if it's like in 5-9 months ..it takes a while ..for some airlines

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Answer:
when you buy the ticket the card is charged (as the fare could change)
now which would yiu prefer the fare today or the fare which could be highe on the day of the flight?