Explanation
Why the waste happens and who it affects.
Snapshots may have been created for backups, migrations, or disaster recovery plans but were never deleted - even after the related workload or volume was decommissioned. Over time, these unused snapshots accumulate, continuing to incur storage costs without providing operational value.
Billing model
The pricing dimensions that drive this cost.
EBS snapshots are billed per GB-month for the total data stored. The first snapshot is a full backup; each subsequent snapshot stores only the changed blocks. Deleting a snapshot removes only the data not referenced by any other snapshot, so savings depend on how much unique data the snapshot holds; data still referenced by newer snapshots is retained and billed to them.
How to detect
How to find it in your estate.
Identify snapshots that have not been used to create a new volume or AMI over a defined lookback period Review snapshot tags, descriptions, and creation context to assess whether they were part of a temporary workflow or a long-term retention strategy Check whether the associated volume or instance still exists, or if the snapshot has become orphaned Validate whether the snapshot is still required for compliance, recovery, or audit purposes
How to fix
How to remove the waste.
Delete snapshots that are no longer needed or are linked to resources that no longer exist. A snapshot used by a registered AMI can be deleted only after the AMI is deregistered, and snapshots that match a Recycle Bin retention rule stay in the Recycle Bin, billed at the normal snapshot rate, until the retention period ends. Where retention is required but access is unlikely, document the business reason and implement lifecycle policies to automatically expire outdated snapshots. Consider tagging new snapshots with creation intent and retention timelines to support better cleanup workflows in the future.
Documentation
Vendor references for pricing and configuration.