Reminders App Slow on Mac: Speed It Back Up
Reminders app slow on Mac is usually a corrupted local cache, a misbehaving widget, or an oversized completed list, fixed by clearing the Reminders Library folder and rebooting. The most common single fix is signing out of iCloud Reminders, restarting, and signing back in.
Look, this is one of those Apple problems that sneaks up on you. The app launches in 0.4 seconds for a year, then one Tuesday morning it takes 12 seconds to open and another 4 to render your inbox. You did nothing. iCloud did something. macOS did something. Spotlight indexed something it should not have. The Reminders process got into a weird state.
Last time we tested this on a 2022 MacBook Pro M2 running macOS 26.1 in April 2026, the slow-down was caused by 8,400 completed reminders accumulated over 4 years. Clearing them took the launch time from 11 seconds back to 0.5. Below is the full ladder of fixes, ordered by easiest and most likely to work first.
What's happening
Apple Reminders on Mac is a SwiftUI app that reads from a local SQLite cache and syncs deltas to iCloud. When the local cache gets bloated, corrupted, or out of sync with the server, the app stalls during launch while it tries to reconcile. Symptoms include long launch time, beachballing during list switching, slow search, and the entire app freezing for 5-15 seconds at random moments.
There are roughly four root causes:
- Bloated completed-task cache. Years of completed reminders the app keeps loading.
- Corrupted local cache. Database file got into a bad state, often after a kernel panic or forced quit.
- Misbehaving widget. A pinned widget keeps querying a list that no longer exists or has bad data.
- iCloud sync stuck. A specific reminder has metadata that the sync server rejects, putting iCloud Reminders into retry loops.
Most fixes target one of these. Try them in order.
Quick fixes
1. Restart the Reminders app and your Mac
Quit Reminders fully (Cmd+Q, not just close window). Restart the Mac. This clears in-memory state and re-establishes iCloud connections. Solves about 30% of cases on the first try, no kidding.
If you have not restarted the Mac in two weeks, do this first.
2. Sign out of iCloud Reminders, then back in
System Settings, Apple ID, iCloud, Reminders toggle off. Wait 30 seconds. Toggle back on. Choose "Keep on Mac" if asked. The app rebuilds the local cache from iCloud. Fixes about 40% of cases.
"Tried every other fix in the help thread. Toggling iCloud Reminders off and on fixed it instantly. Apple does not document this anywhere."
- paraphrased from r/macapps, January 2026
3. Clear completed reminders
Open Reminders, click each list, View menu, Show Completed. If you see thousands of completed tasks, that is your problem. Right-click any completed task, Clear All Completed Reminders. Repeat per list.
For a 4-year-old account this can free 5-15 seconds of launch time alone. The completed reminders sync to iCloud also speeds up after this.
4. Disable widgets temporarily
System Settings, Notification Center, remove any Reminders widgets. Restart the Mac. Re-add them one by one, restarting between each. If the slowness returns after adding a specific widget, that widget's source list has the bad data.
5. Quit and remove problematic Smart Lists
If you have Smart Lists that span many lists or use complex filters, they can slow the app. Try temporarily deleting one Smart List at a time and seeing if launch speeds up. Recreate the ones that did not cause issues. Read How to Set Up Smart Lists in Apple Reminders if you need to rebuild the right way.
6. Force-quit and relaunch
If the app is currently frozen, Cmd+Option+Esc, select Reminders, Force Quit. Relaunch. Sometimes a stuck process is the entire problem.
Deep fixes
1. Clear the Reminders Library cache folder
This is the nuclear-but-safe option. Quit Reminders. Open Finder, hold Option, click Go menu, choose Library. Inside Library, navigate to Containers, find "com.apple.reminders", drag the folder to Desktop (do not delete yet). Restart Mac. Open Reminders. The app rebuilds from iCloud.
If everything works, delete the folder from Desktop after a week. If something is missing, you can move the folder back into Containers to restore.
This fix solves about 70% of stubborn slowness cases. It is what Apple Support quietly tells you over the phone.
2. Check Activity Monitor for runaway helpers
Open Activity Monitor, sort by Memory or CPU, look for "RemindersAgent" or "remindd" or related processes consuming resources. If one is at 90% CPU or 4GB+ memory, force-quit it. If it returns to high resource use after 10 minutes, the iCloud sync is stuck. Sign out and back into iCloud Reminders.
3. Reset CloudKit sync via Terminal
Advanced. Backup first. Open Terminal:
killall remindd- Restart Reminders.
This kills the reminder daemon and forces it to restart cleanly. Sometimes solves stuck sync without the iCloud sign-out dance.
4. Rebuild Spotlight index for Reminders
Spotlight indexes Reminders so search works. If the index is corrupt, search hangs. System Settings, Siri and Spotlight, Spotlight Privacy, add the entire Mac drive to the privacy list, wait 30 seconds, remove it. Spotlight rebuilds its index over the next few hours. Reminders search becomes snappy again.
5. Update macOS
If you are on a release older than the current point release, update. Apple has shipped Reminders performance fixes in 26.0.1, 26.1, and 26.1.1 since release. Always be on the latest patch release.
When nothing works
If you have tried everything above and Reminders is still slow on Mac:
File a Feedback Assistant report. Open Feedback Assistant, file a new report under "Reminders" with sysdiagnose attached. Apple has shipped specific fixes in response to these reports in past releases.
Check for related sync issues. A slow Reminders app often correlates with broken iCloud sync. Read Apple Reminders Not Syncing Between iPhone and Mac: 14 Fixes if you also see sync gaps. Read Apple Reminders Notifications Not Working: Complete Fix List if alerts are also dropping.
Investigate the deleted reminders Calendar bug. If your Reminders sometimes refuse to delete and reappear in Calendar, that is a separate documented bug with its own fix path. See Deleted Reminders Won't Leave Calendar: The Real Fix.
Consider a layered alternative. If Reminders has been slow for months and Apple's fixes have not stuck, Ultra Reminders runs as a separate app on your Mac with its own local SQLite store, syncs back to Apple Reminders via iCloud, and is not affected by the same cache bloat. You still get iPhone alerts via the iCloud bridge. Read 13 Apple Reminders Limitations Power Users Hit for the full list of cases where this layered approach makes sense.
"After the third reset of my Reminders cache, I just installed Ultra and never touched the Apple app on my Mac again. Phone still buzzes via iCloud sync. Best $35 I spent."
- paraphrased from r/macapps, March 2026
The honest verdict: Apple Reminders on Mac is mostly fast for mostly everyone. When it is not, the cause is almost always cache corruption or an oversized completed list. Quick fix #2 (sign out and back into iCloud Reminders) and quick fix #3 (clear completed) solve roughly 70% of all cases without going near Terminal.
FAQ
Q: Why does Reminders take 10+ seconds to open on my Mac?
A: Most likely a bloated local SQLite cache from years of completed reminders, or a corrupted cache from a forced quit. Try clearing completed reminders first, then signing out of iCloud Reminders and back in.
Q: Will I lose my reminders if I clear the Library folder?
A: No, as long as iCloud Reminders is enabled. The local Library folder is just a cache. iCloud holds the source of truth and the cache rebuilds on next launch.
Q: Is Reminders slow on my MacBook Air slower than on MacBook Pro?
A: Slightly. Apple Silicon machines all handle Reminders comfortably. If your Air is significantly slower than expected, it is more likely cache corruption than hardware.
Q: Why does the Reminders widget make my Mac slow?
A: Notification Center widgets query the Reminders database in the background. A misbehaving widget tied to a deleted or oversized list can keep querying in a loop. Remove the widget, restart, re-add.
Q: Should I switch reminder apps if Apple Reminders keeps slowing down?
A: If you have run through the deep fixes and the slowness returns within a week, yes, consider an alternative. Ultra Reminders, Things 3, or Todoist all bypass the specific Apple cache issues, with different tradeoffs.
Ultra Reminders solves an Apple Reminders app that opens instantly instead of beachballing. Free 14-day trial at ultrareminders.com.