Cancels an internal, direct, Airbnb or VRBO reservation by its Host Tools reservation ID. Requires the reservations:write scope.

Airbnb: the reservation is cancelled on Airbnb, which needs a reason. Get the reasons Airbnb accepts right now, and the penalty the host would pay, from /api/getCancellationOptions/{reservationID}, and send one reason (with its subReason, when it has one) exactly as listed. Cancelling on Airbnb can't be undone.

VRBO: the reservation is cancelled on VRBO with a refund to the guest, as the VRBO owner app's "Cancel reservation" does. Get the reasons and refund options VRBO offers right now from /api/getCancellationOptions/{reservationID}, and send one reason's value as reason with a customReason of the length customReasonLength gives, and one of that reason's refundOptions as refundPercentType. refundAmount defaults to the chosen refund option's refundTotal, and is required when that option has none; message is a note to VRBO with the cancellation, which VRBO may not show the guest. A value VRBO doesn't offer is a 400; a cancellation VRBO refuses is a 409 with VRBO's text. Cancelling on VRBO can't be undone.

VRBO counts a cancellation sent this way as the host's, whoever asked for it, with the market-rank and fee consequences VRBO applies to host cancellations. When a VRBO guest has asked to cancel (cancellationRequestedDate is set), VRBO's own advice is to have the guest cancel from their VRBO account, which avoids those; VRBO has no call for the host to approve or decline a request. Cancelling here with the reason GUEST_NEEDS_TO_CANCEL (a full refund) is the fallback.

Internal and direct reservations need no body. Booking.com reservations must be cancelled on the channel.

A stay that has already ended can't be cancelled. If the reservation is already cancelled, the endpoint returns success (idempotent).