OneDrive is pitched as cloud storage, but every file you save to it lives on your PC too — unless you explicitly tell Windows to keep it online-only. On default settings, a 500 GB OneDrive fills 500 GB of your C: drive.

Short answer: right-click the OneDrive folder in File Explorer and choose Free up space. That converts every local copy into an online-only placeholder via Files On-Demand, reclaiming the disk space without deleting anything from the cloud.

Files On-Demand explained

Windows ships OneDrive with Files On-Demand enabled by default. Each file in OneDrive has one of three statuses, visible as a cloud or checkmark icon next to it:

  • Online-only (blue cloud) — metadata only on disk, ~0 bytes
  • Locally available (green checkmark) — full file cached on disk
  • Always keep on this device (solid green checkmark) — pinned, cannot be evicted

When you open an online-only file, Windows streams it from the cloud on demand — it becomes "locally available" automatically. Close it and Windows may evict it later to free space.

Freeing space without breaking OneDrive

  1. open File Explorer > OneDrive
  2. right-click a folder or file > Free up space
  3. status icons switch from green checkmarks to blue clouds
  4. disk space is reclaimed immediately — the cloud copy is untouched

If Free up space is missing:

  1. click the OneDrive cloud icon in the system tray
  2. Settings (gear) > Settings > Sync and backup > Advanced settings
  3. toggle Files On-Demand On
  4. right-click the folder again — the option is now available

When OneDrive still stays heavy

Pinned files (marked Always keep on this device) never evict. Check:

  1. right-click suspicious folders > Free up space (overrides any "Always keep" flag on descendants)
  2. or right-click > Always keep on this device to toggle the pin off

Also check the OneDrive Recycle Bin — deleted cloud files still count against quota but not disk.

Better next routes

For the broader Windows cleanup, continue with How to Free Up Space on C Drive Windows 11 Natively.

For the cross-platform diagnosis catch-all, read Storage Space Running Out: How to Check What's Taking Up Space.