When connecting your Booking.com account you will be asked for the Accommodation ID of the property or properties you want to connect.
There are two places where you can find the listing's Accommodation ID on the Booking.com Extranet:
On the Group Homepage
This page displays the listing Accommodation ID for all of your listings.
On the individual listing page.
You will find the Accommodation ID at the top of the page, right next to the name of the listing.
Note: The Accommodation ID number that you use for the purpose of connecting your listing to Hospitable should not be the "Room ID" number that you see on the listing's Calendar page on the Booking.com Extranet!