what is the official process for increasing storage from 5 TB to 10 TB to 25 TB

For OneDrive for Business, the official process and eligibility to go beyond 5 TB are as follows.

1. Understand plan-based limits

From the OneDrive service description:

• Most business/enterprise plans (for example Microsoft 365 E3/E5, Business plans) provide:
  • 1 TB per user by default.
  • For eligible enterprise plans, this can be increased up to 5 TB per user.
• Pooled storage limits still apply at the tenant level.

For education plans (A3/A5, etc.):

• Up to 1 TB per user by default.
• For subscriptions with at least 5 users, OneDrive for Business provides up to 5 TB per user.
• Qualifying customers with paid storage licenses can request more, up to a maximum of 25 TB per user.

Details are in the OneDrive service description and Office 365 Education service description.

2. Increase default storage up to 5 TB (tenant-level setting)

Admin steps to set the default OneDrive storage (for new and existing users without a per-user override):

Using SharePoint admin center:

1. Go to the SharePoint admin center Settings page.
2. Select the OneDrive Storage limit setting.
3. In Default storage limit, enter the value in GB (for example, 1024 for 1 TB, 5120 for 5 TB), then select Save.

Using PowerShell:

1. Install the latest SharePoint Online Management Shell.
2. Connect as a SharePoint Administrator.
3. Run:

      Set-SPOTenant -OneDriveStorageQuota <quotaInMB>
   

   Example values:
   • 1 TB: 1048576
   • 5 TB: 5242880
   To reset an existing user’s OneDrive to the new default, run:

      Set-SPOSite -Identity <userOneDriveUrl> -StorageQuotaReset
   

Note: If a quota greater than the license allows is set, the user’s storage is rounded down to the maximum allowed by the license.

3. Set or change storage for a specific user (up to the licensed max)

If a specific user needs a different quota (for example, up to 5 TB):

Using PowerShell:

1. Install the latest SharePoint Online Management Shell.
2. Use the provided script or Set-SPOSite to set:
   • Storage Quota in MB.
   • Storage Quota Warning Level in MB.

Reference conversion table from the documentation:

• 1,048,576 MB = 1 TB
• 5,242,880 MB = 5 TB

4. Official process to go beyond 5 TB (up to 25 TB)

For enterprise and qualifying education customers, going from 5 TB up to 25 TB per user is not done by self-service quota alone; Microsoft must enable it per user after eligibility is verified.

Official process (per Microsoft guidance):

1. The user must have already filled at least 90% of the existing 5 TB OneDrive storage.
2. A Microsoft 365 administrator runs the official diagnostic in the Microsoft 365 admin center:
   • Use the “Check OneDrive site eligibility for increased storage” diagnostic.
   • In Run diagnostics, enter the user’s UPN and run the tests.
3. If the diagnostic confirms the OneDrive site can exceed the 5 TB quota, select Update Settings in the diagnostic to process the increase.
4. After Microsoft increases the limit, the admin can then set a specific storage limit for that user (for example, 10 TB or up to 25 TB, within what Microsoft has enabled) via:
   • Microsoft 365 admin center, or
   • PowerShell (Set-SPOSite with the desired StorageQuota in MB).

Important notes from the official guidance:

• This diagnostic-based process is not available for GCC High, DoD, Microsoft 365 operated by 21Vianet, and Microsoft Education customers (for this specific diagnostic; education has its own support path as noted below).
• Users who reach at least 90% of 25 TB will be provided additional cloud storage via a 25 TB SharePoint team site (for eligible enterprise customers); Microsoft Support must be contacted for assistance.
• For Education (A3/A5, etc.), the maximum OneDrive storage per user is 25 TB; pooled tenant limits still apply. Qualifying customers request additional storage by contacting Microsoft Support as described in the education service description.

5. Applicability to small business vs enterprise

The documented “beyond 5 TB” process (diagnostic to increase a user’s OneDrive beyond 5 TB and up to 25 TB) is described for:

• Eligible enterprise and government cloud customers.
• Qualifying education customers (via Microsoft Support).

The OneDrive service description explicitly states that:

• Eligible enterprise and government cloud customers should work with Microsoft representatives for additional storage requirements.

For small business plans (for example, Microsoft 365 Business Basic/Standard/Premium), the documentation in context only covers increasing default storage up to 5 TB per user. There is no additional, separate small-business-only process described beyond that.

Summary of official steps:

• Up to 5 TB: Admin sets tenant default and/or per-user quotas (SharePoint admin center or PowerShell) within license limits.
• Beyond 5 TB up to 25 TB: Admin uses the official OneDrive storage eligibility diagnostic (for eligible enterprise tenants) after the user reaches 90% of 5 TB, then adjusts per-user quota after Microsoft enables the higher limit; education tenants request via Microsoft Support, with a 25 TB per-user maximum.

References:

• Check OneDrive site eligibility for increased storage
• OneDrive service description
• Set the default storage space for OneDrive users
• Change a specific user's OneDrive storage space
• Microsoft storage FAQs
• Office 365 Education service description