AWS Billing and Cost Management
User Guide (Version 2.0)

On-Demand Capacity Reservations

Capacity Reservations enable you to reserve capacity for your Amazon EC2 instances for any duration in a specific Availability Zone. This enables you to create and manage capacity reservations separately from the billing discounts offered by Regional Reserved Instances (RIs). To benefit from billing discounts, you can use Regional RIs in conjunction with Capacity Reservations.

Capacity Reservation Line Items

You can use some of the columns defined in the AWS Cost and Usage report data dictionary to track your Capacity Reservations. You can use the following columns:

ResourceId

If you included resource IDs when you created your AWS Cost and Usage report, you can use the ResourceId column to identify and track your Capacity Reservations.

Capacity Reservations always have an cr- in their resource ID, and the resource ID has the following format:

arn:aws:ec2:<region>:<account id>:<capacity-reservation>/cr-0be443example1db6f

The Capacity Reservation ResourceId is captured only for the UnusedBox, UnusedDed, Reservation, and DedicatedRes UsageTypes.

For more information about the ResourceId, see ResourceId.

UsageAmount

The UsageAmount column describes how much of a Capacity Reservation you used. Each Capacity Reservation can have multiple slots for an hour, enabling you to run more than one instance that uses the reservation during an hour. This mean that it's possible to use more than one instance-hour in an hour. UsageAmount is calculated by multiplying the number of instance slots covered by the line item with the number of hours covered by the line item.

For more information and examples about the UsageAmount, see UsageType.

UsageType

The UsageType column shows how much of a specific reservation you used. For Amazon EC2, the options are the following:

Reservation

For a UsageType of Reservation, the UsageAmount column describes how many instance-hours of a Capacity Reservation that you reserved.

For example, if a report covers one hour and has a Capacity Reservation line item that can cover ten instances, the Reservation UsageAmount covers the number of instance slots that you reserved. In this case, that's 10 (the number of available instance slots) multiplied by 1 hour (the time covered by the report) for a total of 10. For a report that covers 1 day, the UsageAmount would be 10 multiplied by 24, for a total of 240.

DedicatedRes

For a UsageType of DedicatedRes, the UsageAmount column describes how many instance-hours of a dedicated Capacity Reservation that you reserved.

UnusedBox

For a UsageType of UnusedBox, the UsageAmount column describes how many instance-hours of a Capacity Reservation that you reserved but didn't use.

For example, suppose a report covers 1 hour and has a Capacity Reservation line item that can cover 10 instances. If you didn't use eight instance-slots during the time period covered by the report, the UnusedBox UsageAmount covers the number of instance hours that you reserved but didn't use. In this case, that's eight (the number of unused instance slots) multiplied by 1 hour (the time covered by the report) for a total of eight. For a report that covers 1 day, the UsageAmount is eight multiplied by 24, for a total of 192.

UnusedDed

For a UsageType of UnusedDed, the UsageAmount column describes how many instance-hours of a dedicated Capacity Reservation that you reserved but didn't use.

BoxUsage

For a UsageType of BoxUsage, the UsageAmount column describes how many instance-hours of an instance that you used.

For example, suppose a report covers 1 hour and has a Capacity Reservation line item that can cover 10 instances. If you use two instance-slots during the time period covered by the report, the BoxUsage UsageAmount covers the number of instance hours that you reserved and used. In this case, that's two (the number of used instance slots) multiplied by 1 hour (the time covered by the report) for a total of two. For a report that covers 1 day, the UsageAmount is two multiplied by 24, for a total of 48.

For more information about the UsageType, see UsageType.

UnblendedRate

For Capacity Reservations with a UsageType of Reservation or DedicatedRes, the UnblendedRate is 0. This is because the costs for the Capacity Reservation are associated with the instance that provides the capacity instead of with the Capacity Reservation itself.

For more information about the UnblendedRate, see UnblendedRate.

UnblendedCost

For Capacity Reservations with a UsageType of Reservation or DedicatedRes, the UnblendedCost is 0. This is because the costs for the Capacity Reservation are associated with the instance that provides the capacity instead of with the Capacity Reservation itself.

For more information about the UnblendedCost, see UnblendedCost.

BlendedRate

For Capacity Reservations with a UsageType of Reservation or DedicatedRes, the BlendedRate is 0. This is because the costs for the Capacity Reservation are associated with the instance that provides the capacity instead of with the Capacity Reservation itself.

For more information about the BlendedRate, see BlendedRate.

UnblendedCost

For Capacity Reservations with a UsageType of Reservation or DedicatedRes, the UnblendedCost is 0. This is because the costs for the Capacity Reservation are associated with the instance that provides the capacity instead of with the Capacity Reservation itself.

For more information about the UnblendedCost, see UnblendedCost.