Inactive S3 Bucket

Service Category

Storage

Cloud Provider

AWS

Service Name

AWS S3

Inefficiency Type

Unused Resource

Explanation

S3 buckets often persist after projects complete or when the associated workloads have been retired. If a bucket is no longer being read from or written to—and its contents are not required for compliance, backup, or retention purposes—it represents ongoing cost without delivering value. Many organizations overlook these idle buckets, especially in shared or legacy accounts, leading to unnecessary storage costs over time.

Relevant Billing Model

S3 charges based on the total storage used (per GB per month), the selected storage class, and the number and type of requests made (PUT, GET, LIST, etc.). Storage costs accrue continuously, even if the data is never accessed. Buckets with no read or write activity still incur storage charges for all retained data.

Detection

Identify S3 buckets with no read or write activity during the defined lookback period
Review object access patterns to confirm that stored data is not being queried or updated
Check whether the bucket was associated with a decommissioned workload, environment, or application
Assess whether the data is still needed for compliance, reference, or future recovery
Validate with data owners or security stakeholders before making changes

Remediation

If a bucket is confirmed to be inactive and nonessential, delete the bucket and all stored objects. Alternatively, move the data to a lower-cost storage class such as Glacier Flexible Retrieval or Deep Archive for long-term retention at reduced cost. Consider applying lifecycle policies going forward to automatically clean up inactive data.

Relevant Documentation