Consolidating Multiple AWS Accounts Into an Org
Log into the AWS account that you wish to be the parent AWS account, master of all the other AWS accounts. This matters because the master will get a special black star icon next to it.
Open AWS Organizations in your AWS console.
Click the button to create an AWS org. It's a bit scary, but just do it 😃
You'll be asked to verify your email so you can invite other AWS accounts. Do it and then invite another AWS account. Just click through and follow the process.
Now in the master account you should see a Tree view page showing both accounts. Nice!