Retention Policy vs. Litigation Hold vs. Archiving in Exchange Online

26 Oct 2021

8 min read

Ragavarshini

Article at a glance

Microsoft 365’s retention policies, litigation hold, and archiving features are essential but come with limitations that could result in data loss.

Retention policies manage data for compliance but can be complex to set up and may not cover all scenarios, leaving some data vulnerable.

Litigation holds are designed to preserve data during legal proceedings but don’t offer the flexibility needed for general data recovery.

‘Archiving’, ‘retention policies’, and ‘litigation holds’ are different terms related to Exchange Online data retention, and administrators should be aware of when to use what.

In this article, we discuss in detail how retention policies, litigation holds, and archive mailboxes are different from each other, and explain how they should be used.

Retention policies and labels

Retention policies in Microsoft 365 are rules that can be created to govern business information, comply with industry-related data retention requirements, and prevent data loss instances. They are part of an organization’s overall information governance strategy as they cover different types of data including mailboxes, Teams conversations, as well as SharePoint and OneDrive data.

Retention policies are applied at an organizational level and can be applied to specific data locations after deciding whether to retain content, delete content, or retain the content for a period and then delete it.

Note: Microsoft uses the term ‘retention policies’ in various contexts. In this article, retention policies and labels refer to the new Microsoft 365 retention policy features available in the Compliance Center.

Click here to know more about Microsoft 365 retention policies and labels.

Litigation holds

Litigation hold helps you place user mailboxes on hold, i.e., retain all the contents of a mailbox, including deleted items and the original versions of modified items. It is not a general retention feature, rather, it is an eDiscovery feature in Exchange Online. When a mailbox is placed on litigation hold, items in the user's primary and the archive mailboxes (if enabled) are retained. Litigation holds must be manually applied to user mailboxes.

Click here to know more about litigation holds in Microsoft 365.

Archiving

In Microsoft 365, archive mailboxes refer to the additional mailbox storage space provided to users.

The primary intent for using archive mailboxes is for users to move data that they no longer use currently to a secondary mailbox. This helps save storage costs associated with the primary mailboxes.

After the archive mailbox is enabled, up to 100 GB of additional storage is available per user. Once the limit is reached, users can make use of a feature called auto-expanding archiving (also called unlimited archiving) that provides additional storage in the archive without contacting Microsoft. However, there is a limit of 1.5 TB to the auto-expanded archive.

For step-by-step instructions on how to turn on auto-expanding archiving, click here.

To understand unlimited archiving in detail, click here.