Long-Retained Azure Snapshot

Anderson Oliveira

Service Category

Storage

Cloud Provider

Azure

Service Name

Azure Snapshots

Inefficiency Type

Retained Unused Resource

Explanation

Snapshots are often created for short-term protection before changes to a VM or disk, but many remain in the environment far beyond their intended lifespan. Over time, this leads to an accumulation of snapshots that are no longer associated with any active resource or retained for operational need.Since Azure does not enforce automatic expiration or lifecycle policies for snapshots, they can persist indefinitely and continue to incur monthly storage charges. This inefficiency is especially common in development environments, migration efforts, or manual backup workflows that lack centralized cleanup.Snapshots older than 30–90 days, especially those not tied to a documented backup strategy or workload, are strong candidates for review and removal.

Relevant Billing Model

Snapshots are billed based on the amount of data stored (per GB/month)
Charges accrue regardless of whether the snapshot is used or linked to an active disk
Incremental snapshots are more space-efficient but still incur storage cost

Detection

List all snapshots in the subscription
Filter for snapshots not associated with any currently active managed disk
Review creation timestamps to identify snapshots older than a defined threshold (e.g., 30 or 90 days)
Cross-reference with project timelines, VM decommissioning dates, or change records to validate relevance
Use Azure Resource Graph or scripting to automate identification at scale

Remediation

Manually review long-retained snapshots with application or infrastructure owners
Delete snapshots no longer needed for recovery, rollback, or compliance retention
Adopt tagging standards to track purpose, owner, and expected retention period at time of snapshot creation
Incorporate snapshot lifecycle reviews into infrastructure decommissioning or backup policy audits

Relevant Documentation