Commitment Adjustment Fees
After joining Antimetal, your bill at the end of each billing cycle will largely reflect your costs found from AWS Cost Explorer. If the costs differ, they will be denoted in your invoice as Commitment Adjustment Fees.
What are Commitment Adjustment Fees?
Most AWS accounts under the Antimetal Organization have commitments. These can be Savings Plans, Reserved Instances, CloudFront Security Bundles, etc. Commitments are applied first to the owner account but will flow to others accounts in the organization if they go underutilized - thereby generating savings for other accounts. This is great for both parties, the owner account that purchased the commitments don't have to pay for their underutilized commitments while other accounts (beneficiary accounts), get a discount from a commitment they didn't purchase. The official AWS explanation can be found at this AWS documentation.
This is great for both parties but it does introduce an extra layer of billing complexity since the account that purchased the commitment is no longer the same account that is using it. AWS doesn't support this billing redistribution natively so Antimetal handles this redistribution by referencing Cost And Usage Report 2.0.
Antimetal ingests the Cost And Usage Report and redistributes the effective-cost of a commitment (the fees of the commitment) when it flows across the organization to another account.
To demystify this with an example: if owner account has a commitment of $100 in Compute Savings Plans and it flows cross-organization to negate $130 from the compute workload of a beneficiary account, Antimetal will redistribute the effective-cost of the Savings Plans by reimbursing the owner account $100 and passing this commitment fee to the beneficiary account. On net, the beneficiary account saved $30 they otherwise wouldn't have and the owner account recoups $100 they otherwise would've lost.
To emphasize, Antimetal does not take a fee from savings. This redistribution system is simply put in place for the advantage of our customers.
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