A Microsoft file hosting and synchronization service.
OneDrive caches previews and temporary files locally for performance. Over time, this can grow significantly, especially if you’ve opened large files or media. Since iOS doesn’t provide a direct Clear Cache option in OneDrive, offloading the app is the most effective solution.
Here’s what you can try:
Check for offline files
In the OneDrive app, go to Offline (as shown in your screenshot).
If it’s empty, then the space is mostly cache.
Clear OneDrive cache manually
iOS doesn’t allow clearing cache from the app directly, so you need to:
Go to Settings > General > iPhone Storage > OneDrive.
Tap Offload App (this removes the app but keeps documents).
Then reinstall OneDrive from the App Store.
This will clear all cached data without deleting your cloud files.
Reduce future cache growth
Avoid opening very large files repeatedly if you don’t need them offline.
Keep the app updated Microsoft sometimes improves cache handling in newer versions.
Let me know how it goes, happy to help!