Join Organization as Existing Account

When you add an individual AWS account to an AWS Organization, the resources within that account remain operational and unchanged. Joining an organization primarily affects billing and centralized management. However, there are a few things to keep in mind:

1. Service Control Policies (SCPs): Once your account is part of an AWS Organization, it can be affected by SCPs. These policies define what services and actions the entities in the organization can and cannot use. If there's an SCP that denies a particular service, then that service will not be available in the member accounts. Ensure you review and understand any SCPs applied at the organizational level.

2. Consolidated Billing: The AWS Organization's master account will now receive the bills for the account you've added. Ensure that billing information and limits are adjusted accordingly.

3. Account Settings: Account-specific settings (like AWS Regions enabled, IAM users, and resource limits) remain unchanged when you join an organization.

4. Organization-wide Features: Once part of an organization, you might have access to features like AWS service discounts, consolidated billing, or enterprise support, depending on your organization's setup and plans.

5. Review and Test: It's always a good practice to review and test critical services after making significant changes to account structures, even if disruptions are not expected.

As always, before making changes, it's advisable to read the AWS documentation specific to AWS Organizations and consult AWS support or solutions architects if you have specific concerns or complex setups.