There is no additional charge for AWS Systems Manager. You only pay for your underlying AWS resources managed or created by AWS Systems Manager (e.g., Amazon EC2 instances or Amazon CloudWatch metrics). You only pay for what you use, as you use it; there are no minimum fees and no upfront commitments.
Additional Pricing Resources
TCO Calculator
Calculate your total cost of ownership (TCO)
Simple Monthly Calculator
Easily calculate your monthly costs with AWS
Economics Resource Center
Additional resources for switching to AWS
Get started with AWS Systems Manager