Your Microsoft 365 storage allocation depends on which plan your users are licensed for and how many seats you hold. The tables below cover both the SharePoint Online tenant storage pool (shared across all site collections) and the per-user OneDrive for Business allocation.
SharePoint Online Tenant Storage Pool
SharePoint Online storage is pooled at the tenant level, with all site collections drawing from the same shared pool. The formula is the same regardless of which Microsoft 365 plan you hold.
| Component | Allocation | Example (200 users) |
|---|---|---|
| Base tenant storage | 1 TB | 1 TB |
| Per-user addition | 10 GB per licensed seat | 2 TB (200 x 10 GB) |
| Total pooled storage | 1 TB + (10 GB x users) | 3 TB |
This pool is shared across all SharePoint site collections, Microsoft Teams sites, and SharePoint-backed group sites in the tenant. Admins can set storage limits per site collection within the total pool. Individual site collections can reach up to 25 TB; the maximum size for a single file is 250 GB.
OneDrive for Business Storage by Plan
OneDrive for Business storage is per-user and separate from the SharePoint pool. Each user's license determines their OneDrive quota.
| Plan | OneDrive Storage per User | Notes |
|---|---|---|
| Microsoft 365 Business Basic | 1 TB | Pooled with additional storage on qualifying tenants |
| Microsoft 365 Business Standard | 1 TB | |
| Microsoft 365 Business Premium | 1 TB | |
| Microsoft 365 Apps for Business | 1 TB | No Exchange Online included |
| Office 365 E1 / Microsoft 365 E1 | 1 TB | |
| Office 365 E3 / Microsoft 365 E3 | 1 TB (expandable) | Large tenants (5+ qualifying seats) can request expanded allocations from Microsoft |
| Office 365 E5 / Microsoft 365 E5 | 1 TB (expandable) | Same expansion eligibility as E3 |
| Microsoft 365 F1 (Frontline) | 2 GB | Frontline worker plan; limited OneDrive access |
| Microsoft 365 F3 (Frontline) | 2 GB | |
| OneDrive for Business Plan 1 | 1 TB | Standalone OneDrive license |
| OneDrive for Business Plan 2 | Unlimited (expandable) | Qualifying tenants; Microsoft provisions on request |
Important: OneDrive and SharePoint storage pools are independent. A user's OneDrive quota does not draw from the SharePoint tenant pool, and vice versa.
What Counts Against Your Storage Quota
Both pools count the same categories of content against storage usage:
| Content Type | Counted? | Notes |
|---|---|---|
| Current file versions | Yes | Every live file in every library and OneDrive |
| Previous file versions | Yes | Often the largest contributor; see versioning defaults reference |
| First-stage recycle bin | Yes | Items deleted by users, retained up to 93 days |
| Second-stage recycle bin | Yes | Items cleared from the user bin, up to 93 days total |
| Site Pages and web parts | Yes | Stored in the Site Pages library |
| List attachments | Yes | Files attached to SharePoint list items |
| Teams channel files | Yes | Stored in the backing SharePoint site's document library |
| Email in Exchange Online | No | Exchange has its own per-mailbox quota, separate from SharePoint/OneDrive |
Version history and the recycle bin are the two most common sources of unexpected storage consumption. Tenants that have never run a version trim can find that version history alone exceeds their live file storage several times over. The SharePoint storage reduction guide covers the steps to reclaim that space efficiently.
Frequently Asked Questions
What happens when a SharePoint Online tenant exceeds its storage quota?
When a tenant reaches its storage quota, users can no longer upload new files or create new content in SharePoint Online or OneDrive for Business. Existing content remains accessible and readable. Admins receive email alerts from the Microsoft 365 message centre as the tenant approaches 90% and 100% of its quota.
Can you buy additional SharePoint Online storage?
Yes. Microsoft offers additional SharePoint Online storage as a paid add-on, available through the Microsoft 365 admin centre under Billing. Adding more licensed users also increases the pooled storage automatically at 10 GB per seat - so scaling the user count is sometimes more cost-effective than buying raw storage.
Does OneDrive storage count against the SharePoint Online quota?
No. OneDrive for Business storage and SharePoint Online storage are separate pools. Each user's OneDrive draws from that user's per-user allocation defined by their license plan. SharePoint site collections draw from the tenant-level pooled quota. The two are counted independently and do not affect each other.
What is the maximum size of a single SharePoint site collection?
Microsoft supports individual SharePoint Online site collections up to 25 TB in size, provided the tenant's total pooled quota is sufficient to cover it. The maximum size for a single file uploaded to SharePoint Online or OneDrive for Business is 250 GB.
Try ShareMaster free for 14 days