Your credit card will be charged after the host has confirmed your reservation.
When you make a reservation request, you must enter your credit card details to reserve the booking. At this time, the booking amount is temporarily held on your credit card, also called an authorization. You will need to wait for the approval of your host before completing the booking.
Once the host confirms your reservation, the authorization made for the payment of the reservation will become a capture. At this moment your credit card will be charged, and it will be time to start packing!