AWS Standard Account Linking
AWS GovCloud (US) accounts are associated 1:1 with standard AWS accounts for billing, service, and support purposes. Customers are required to have an existing standard account before signing up for an AWS GovCloud (US) account
Important
We recommend creating a new AWS account that will only be used for AWS GovCloud (US) sign up and billing (i.e. do not deploy any AWS workloads into AWS standard account). A dedicated AWS account for the new AWS GovCloud (US) account will enable you to transfer the AWS GovCloud (US) account to another party in the future and fully close the AWS GovCloud (US) accounts without affecting your other AWS workloads.
If you are using AWS Organizations to manage accounts within AWS standard regions, you can
create the new standard account from AWS Organizations console or using the AWS Organizations API
You can create a new AWS Organizations within the AWS GovCloud (US) partition by creating a set of new accounts, creating a new AWS Organizations root within one of the new accounts, and inviting the other AWS GovCloud (US) accounts to the new AWS Organization. Follow the steps for inviting accounts to an organization here. This will result in separate AWS Organization, one in each partition.