Reserved Instances
For billing purposes, the consolidated billing feature of AWS Organizations treats all the accounts in the organization as one account. This means that all accounts in the organization can receive the hourly cost benefit of Reserved Instances that are purchased by any other account.
You can turn off Reserved Instance discount sharing on the Preferences page on the Billing and Cost Management console. For more information, see Reserved Instances and Savings Plans discount sharing.
Note
When you use billing transfer, Reserved Instances and Savings Plans apply only to the AWS Organizations where they're purchased, regardless of which account pays the bill. You can't purchase or share Reserved Instances and Savings Plans across multiple AWS Organizations.