Microsoft OneDrive for Mac Is Raising Its Sync Limit to 1 Million Items

Microsoft is preparing to raise the supported OneDrive sync limit on macOS from 300,000 to 1 million items per sync instance, per device, giving Mac users a significantly larger capacity for syncing extensive OneDrive and SharePoint libraries.

The change is scheduled to enter Public Preview worldwide in mid-October 2026, initially for devices enrolled in Microsoft’s Insiders ring. The preview rollout is expected to finish by late October, with General Availability planned for a later date.

For organizations managing large cloud document libraries, the increase could make it possible to keep substantially more content available through the OneDrive sync client on Mac devices.

OneDrive’s macOS limit is getting a major increase

The existing supported limit for OneDrive sync on macOS is 300,000 items. Microsoft is now extending that ceiling to 1 million items, matching an increase previously announced for OneDrive on Windows.

The limit applies to each sync instance on an individual device. That distinction matters for businesses where employees regularly work with large SharePoint document libraries or extensive OneDrive collections.

Microsoft says the change is intended to help organizations with large OneDrive and SharePoint libraries sync more content reliably across their devices.

For Mac-heavy workplaces, the update addresses a practical limitation that can become increasingly important as organizations move more files and collaboration workflows into Microsoft 365.

The Public Preview starts in October 2026

The first stage of the rollout will be a worldwide Public Preview beginning in mid-October 2026.

Microsoft expects the preview deployment to reach completion by late October 2026.

The initial release is limited to devices enrolled in the Insiders ring, meaning organizations that want to test the higher limit will need to use Microsoft’s preview channel rather than wait for the standard production rollout.

Rollout at a glance

Platform: macOS
Services: OneDrive, OneDrive for Business and SharePoint document libraries
Current item limit: 300,000 items
New item limit: Up to 1 million items
Preview: Public Preview
Preview audience: Devices enrolled in the Insiders ring
Preview start: Mid-October 2026
Expected preview completion: Late October 2026
General Availability: Later, with no specific date announced in the provided notice

Not every Mac will get the higher limit

The million-item limit isn’t being applied universally to every Mac automatically.

Microsoft says devices must meet minimum hardware and configuration requirements to take advantage of the expanded capacity. Those requirements cover factors such as the supported operating system, memory, storage and processor.

Devices that don’t meet the requirements will remain at the existing 300,000-item supported limit.

That’s an important distinction for IT administrators. The update isn’t expected to disrupt existing configurations, but organizations evaluating the preview will need to determine which Macs are capable of handling the higher sync volume.

In practical terms, a user with a large SharePoint library could see a different supported ceiling depending on the hardware and configuration of their Mac.

Who is most likely to notice the change?

The update is primarily relevant to users whose synced libraries are approaching or exceeding the existing 300,000-item threshold.

That could include employees working with large departmental repositories, extensive project archives or organizations that maintain substantial SharePoint document libraries.

Microsoft specifically identifies the following groups as potentially affected:

Users syncing OneDrive or OneDrive for Business on macOS
Users syncing SharePoint document libraries
Users whose libraries contain close to or more than 300,000 items
Organizations participating in the Public Preview through the Insiders ring

For users with smaller libraries, the change may have little visible effect. The larger limit becomes relevant when the volume of synchronized content approaches the current ceiling.

What the 1 million-item limit could mean for organizations

The most obvious impact is capacity. Increasing the limit by more than three times gives organizations considerably more room to synchronize large collections of cloud files to supported Mac devices.

But a higher limit doesn’t automatically mean every organization should sync a million items.

Large-scale synchronization can introduce other considerations, including local storage consumption, indexing, network traffic and client performance. Administrators therefore still need to consider how much content users actually need available locally.

A sensible deployment strategy may involve identifying specific users and devices with a genuine business requirement for very large sync libraries rather than treating the new limit as a reason to synchronize everything.

Key considerations for IT teams

Hardware: Confirm that Macs meet Microsoft’s minimum requirements before testing the higher limit.

Storage: More synchronized items can mean greater demand for local storage, depending on the organization’s OneDrive configuration and users’ file-access patterns.

Configuration: Microsoft recommends reviewing OneDrive and SharePoint sync configuration guidance when preparing for large-scale synchronization.

Support: Helpdesk teams should know that preview participation requires the Insiders ring and that unsupported hardware will continue operating under the existing limit.

Testing: Organizations should evaluate the feature with representative users and libraries before considering broader deployment.

Microsoft warns that some workloads aren’t fully optimized

There is an important caveat for organizations with specialized document libraries.

Microsoft notes that performance is not yet optimized for syncing a high volume of read-only files or for accounts under legal hold.

The company says it is continuing to work on performance and reliability for these scenarios.

That means the million-item ceiling should not be interpreted as a guarantee that every type of million-item library will deliver the same user experience.

For organizations whose large libraries consist heavily of read-only content, or whose accounts are subject to legal holds, testing will be particularly important before relying on the expanded limit for production workflows.

No action is required for most organizations

Organizations that aren’t interested in Public Preview don’t need to make any changes based on this announcement.

Existing configurations are expected to continue operating without disruption. Macs that don’t satisfy the new requirements will simply remain at the current supported limit.

For companies considering an early evaluation, Microsoft recommends identifying users with large OneDrive or SharePoint libraries, checking device requirements and reviewing recommended synchronization configurations.

IT teams should also prepare support staff for questions about the preview and the different limits that may apply depending on device hardware and configuration.

Why the Mac update matters after the Windows increase

The macOS announcement follows Microsoft’s earlier move to increase the OneDrive sync item limit on Windows.

Bringing the same 1 million-item ceiling to supported Mac devices provides a more consistent capacity target across the two major desktop platforms used by Microsoft 365 customers.

That doesn’t mean the experience will be identical on every device. Hardware requirements and workload characteristics remain important, and Microsoft is still working on performance for certain high-volume scenarios.

Still, the change signals Microsoft’s focus on accommodating organizations with increasingly large cloud-based file repositories.

What businesses should watch next

The immediate milestone is the mid-October 2026 Public Preview.

Organizations interested in testing the feature will need to identify suitable Macs and enroll participating devices in the appropriate Insiders ring. Administrators should also establish clear test groups rather than assuming that the higher limit needs to be enabled across an entire organization.

The next significant milestone will be Microsoft’s eventual General Availability release. The source announcement does not provide a specific date for that broader rollout.

Until then, the 1 million-item limit is best viewed as a preview capability for eligible Macs rather than an immediate change to every OneDrive installation.

The bigger picture for OneDrive and SharePoint users

Cloud storage has made it easier for organizations to accumulate enormous collections of documents, but synchronizing those collections to individual computers creates a different set of technical constraints.

Microsoft’s move from 300,000 to 1 million items addresses one of those constraints for supported macOS devices.

The real test will come as organizations begin using the higher limit with large, real-world libraries. Performance, local resource consumption and specialized workloads such as read-only repositories and legal-hold accounts will help determine how useful the expanded capacity is in practice.

For now, Mac users with large OneDrive and SharePoint libraries have a significant change to watch in October: the supported synchronization ceiling is set to rise from 300,000 to as many as 1 million items per sync instance on qualifying devices.