There are a few reasons you may want to close your Amazon Web Services (AWS) Account.
Most of the time it is because you had some level of service with AWS – and now you no longer want these services.
Before you close your account, it may be a good idea to do a survey of all of the services to confirm that they are no longer needed.
The best way to see what you have , is to open the AWS Account – and go to the billing dashboard – and then look through your monthly bill. This helps you identify which services you have, you can use this list to open each of the sections in the AWS Console – select the correct region and review the service.
If you no longer need the service you can delete it.
If you are unsure whether you need it, contact your developer (contact-us)
If you are positive that you are ready to close your AWS Account, you can follow these instructions (these instructions are from this AWS Support Page)