Hardly a day goes by where I don’t have a question about SharePoint storage costs. It is possible to extend SharePoint storage but there is a cost. For many organisations this is a necessary requirement because of compliance requirements or simply because they have a lot of stuff and don’t have the resources to be able to clean up.

There is some good news in the M365 Roadmap (573699), automatic archiving is coming to SharePoint.

“SharePoint administrators can use the Inactive files policy in SharePoint Advanced Management to automatically archive files based on when they were last accessed. The public preview is available through PowerShell only. Admins can set an inactivity threshold from 6 to 48 months, scope policies to all SharePoint sites or selected sites, include or exclude file types and sites, and use What-If mode to review impact before activation. Eligible files move to the Microsoft 365 Archive cold-storage tier while remaining in place and retaining their metadata, permissions, compliance, and searchability. Microsoft 365 Archive and pay-as-you-go billing must be enabled.”

This SharePoint Advanced Management feature is uses M365 Archive with pay-as-you-go. This means it will bill you for the actual amount of storage used by archive, rather than a prepaid bucket. M365 Archive storage costs are 75% less than purchasing additional SharePoint storage, approximately $US0.05 per GB/Month for Archive vs $US0.20 per GB/Month for SharePoint Extra Storage.

Policies are configured using the New-SPOFileArchivePolicy PowerShell commandlet. Parameters include:

• Last accessed date criteria – 6 to 48 months
• File type exclusions criteria – file types to exclude from the policy
• What if mode – allows you to test in report only mode to determine what will be archived
• Policy type – all sites, specific sites or OneDrive

There are additional PowerShell commandlets to update the policy and get reports.

As with manual file archiving, a stub remains in the Document Library, allowing users to rehydrate archived files without needing to call the SharePoint Admin. Content remains searchable, secure and compliant with Purview Retention and Sensitivity. Copilot does not have access to archived content.

Automatic Archiving is in Preview from October 2026 and is expected to be GA in December 2026.