Contacts, Calendar, Notes or Reminders won't sync with iCloud

Why it happens

Each app has its own iCloud switch, so Contacts can sync while Calendar doesn't. If the switch is off on your Mac, nothing from that app goes up or comes down. The other common cause is a Mac and an iPhone signed in to two different Apple Accounts.

How to fix it

1. Open System Settings and click your name at the top of the sidebar.

2. Click iCloud, then See All, and turn on the switch for each app you want to match your other devices: Contacts, Calendars, Notes or Reminders.

   Apple Account›iCloud›See All

3. Do the same on your iPhone. Open Settings, tap your name, then iCloud, tap See All under Saved to iCloud, and turn on Contacts, Calendars, Reminders and Notes there too.

4. Compare accounts. The email shown under your name on the Mac should be the same as the one under your name in Settings on your iPhone.

5. Open the app on your Mac and give it a few minutes on Wi-Fi. New items usually appear soon after.

Still not fixed?

1. New contacts saved On My Mac stay on the Mac. In Contacts, choose Contacts, then Settings…, and set Default Account to iCloud.

   Contacts›Settings…›General

2. New events can land in a calendar that only lives on the Mac. In Calendar, choose Calendar, then Settings…, click General and set Default Calendar to one listed under iCloud.

   Calendar›Settings…›General

3. Events already in a calendar listed under On My Mac won't sync. Move them to a calendar listed under iCloud, or create new events there.

4. Restart the Mac and your iPhone. It's simple, and it often gets a stuck sync moving again.

5. If one app still won't sync after a day on Wi-Fi with both devices on the same account, contact Apple Support.