Outlook Tasks used to sync smoothly with iPhone Reminders, but many users now notice that tasks created on a Windows PC no longer appear on their iPhone. At the same time, reminders created on an iPhone still sync back to Outlook without any problem. This one-way behavior feels confusing, especially when both devices use the same Microsoft account and show no sign of misconfiguration. The issue is not caused by a faulty setup or a recent device update. It happens because Microsoft and Apple changed how task syncing works between their platforms.
This guide explains why Outlook Tasks stopped syncing to iPhone Reminders and shows the correct way to restore reliable task syncing across your PC and iPhone.
Why Outlook Tasks No Longer Sync to iPhone Reminders
Microsoft moved Outlook Tasks into its modern task system powered by Microsoft To Do.
Apple uses its own private system for Reminders inside iOS. These two systems no longer support full two-way syncing.
Today:
- Apple Reminders → can sync into Outlook
- Outlook Tasks → cannot sync back into Apple Reminders
This change affects:
- Microsoft 365 Personal
- Surface Pro and Windows PCs
- iPhone running iOS 17+
- New Outlook desktop app
If everything looks correctly configured, your setup is not broken. The sync model changed.
Fix Outlook Tasks Not Syncing to iPhone
The only reliable fix is to use Microsoft’s official task app on iPhone.
Solution: Use Microsoft To Do on iPhone
Instead of syncing to Apple Reminders, you sync directly with Microsoft’s task system.
Step 1: Install Microsoft To Do
- Download Microsoft To Do from the App Store.
- Sign in with the same Microsoft account you use in Outlook.
Step 2: Confirm Tasks Appear
Open Microsoft To Do on your iPhone.
You should see:
- Tasks created in Outlook
- Flagged emails
- Existing task lists
If they appear here, sync works properly.
Step 3: Stop Using Apple Reminders for Outlook Tasks
Do not rely on Apple Reminders for Outlook-created tasks.
Use Microsoft To Do instead for:
- Creating tasks
- Editing tasks
- Completing tasks
This restores full two-way syncing between PC and iPhone.
Why This Works
Outlook desktop and Microsoft To Do use the same cloud backend. When you create a task in Outlook:
- It saves to Microsoft’s cloud
- It instantly syncs to Microsoft To Do
- It appears on iPhone inside To Do
Apple Reminders does not connect directly to that backend anymore.
Optional: Keep Apple Reminders for Personal Use
If you prefer Apple Reminders for personal notes:
- Use Reminders only for Apple ecosystem tasks
- Use Microsoft To Do for Outlook tasks
Do not mix both systems for the same workflow.
Advanced Troubleshooting (If To Do Doesn’t Sync)
If tasks do not appear in Microsoft To Do:
1. Check Account Consistency
Make sure Outlook on PC and To Do on iPhone use the same Microsoft account.
2. Disable Cached Mode Refresh Issue
In Outlook:
- Go to File → Account Settings
- Confirm your Microsoft 365 account is active
- Restart Outlook
3. Check Default Task Folder
In Outlook:
- Go to Tasks
- Make sure you create tasks inside your main mailbox, not an archive or local PST file.
Tasks saved to local PST files will not sync.
By following the steps above, you can fix Outlook Tasks not syncing with iPhone and restore reliable task updates across your PC and iPhone. This approach works because it uses Microsoft’s supported task system instead of relying on outdated syncing methods. If you still face issues or have questions after trying these steps, comment down below and we’ll help you out.
