Starting today, you can assign the billing of unused Amazon EC2 On-Demand Capacity Reservations (ODCR) to any one of your organization accounts with which the reservation is shared. Capacity Reservations help you reserve compute capacity for any duration and share it across multiple accounts, enabling you to centrally pool and manage your reserved capacity. When a Capacity Reservation is shared, each account is billed for their respective usage of the reservation, while any unused capacity is by default billed to the account that owns the reservation. Now, depending on your business needs, you have the flexibility to configure which account gets billed for the unused capacity.
To get started, you can select any shared reservation and initiate a request to assign its billing to a specific AWS account. Once the request is accepted by the new account, charges for any unused capacity (i.e. the available capacity in your reservation) from that point onward will be billed to the assigned account. As is the case today, billing for any instances running inside the Capacity Reservation is assigned to the respective accounts that launched the instances.
This feature is now available to all Capacity Reservations customers in all commercial AWS Regions and AWS China regions at no additional cost. You can access this feature via AWS Management Console, AWS SDKs, or AWS Command Line Interface (CLI). Click here to learn more about this feature.
Source:: Amazon AWS