Reserved Instances and Consolidated Billing

The pricing benefits of Reserved Instances are shared when the purchasing account is part of a set of accounts billed under one Consolidated Billing Payer account. Consolidated billing allows you to pay all of your charges via one Payer account (the one that will pay the bill). The amount of hourly usage for each month across all child accounts is also aggregated in the parent account. This billing is typically useful for companies in which there are different functional teams or groups.

For Reserved Instances, the amount of usage across all linked accounts is also aggregated in the payer account, by the hour for each month, and then the normal Reserved Instance logic is applied to calculate the bill. The discount is spread across the consolidated account. The allocation of the total cost is determined by the ratio of each child account's usage divided by the total usage of the parent account. However, it is important to note that the capacity reservation remains with the purchasing account. Keep in mind that capacity reservation only applies to the product platform, instance type, and Availability Zone specified in the purchase.

If the account is part of a consolidated billing account, the upfront cost of the Reserved Instance purchases is paid by the Payer account. Additionally, all of the subsequent usage charges will be paid by the payer account as long as the account remains linked with the payer account. However, all of the pricing benefit will also be shared with all of the linked accounts as long as it remains linked to the payer account.

Consolidated billing accounts also benefit from Reserved Instance pricing tiers. For more information, see Understanding Reserved Instance pricing tiers.

To illustrate, we'll expand on the previous example. For the purpose of explaining how billing works, we're simplifying the scenario with the following assumptions:

The following table shows how the consolidated bill would look without the benefit of Reserved Instances purchased by User A.

With User A's purchase of Reserved Instances, the benefit of the discounted rate for six Reserved Instances will be divided across the three accounts under the master account CB AZ. The division will be based on the usage rate:

Master account CB AZ will save a total of $900 in usage fees after the Reserved Instances discounts are applied. The following table shows how the consolidated bill would look with the benefit of Reserved Instances purchased by User A.