Why aren't my Amazon EC2 Reserved Instances applying to my AWS billing in the way that I expected?

Last updated: 2020-12-23

I purchased an Amazon Elastic Compute Cloud (Amazon EC2) Reserved Instance (RI), but it's being used in a way that I didn't expect.

Resolution

If your RI isn't applying to any usage at all, see Why isn't my Reserved Instance applying to my AWS billing?

The most common reason that an RI discount isn't applying to the instance in the way that you expect is that the terms of the RI don't match any instances running on your account. The RI that you purchase must match the platform, type, size (or size footprint), Availability Zone (if applicable), and tenancy of a running On-Demand Instance for it to apply. Check the terms of your RI and the instance it applies to.

If your RI is active and matches the specifications of a running On-Demand Instance, then use Cost Explorer to analyze your spending and usage. You can use AWS Cost Explorer to generate the RI Utilization and RI coverage reports. For more information, see How do I view my Reserved Instance utilization and coverage?

If the RI terms do match the instance that you intended it to apply to, consider the following: