Share a reminder list on Mac
You can share reminder lists in your upgraded iCloud reminders account with other iCloud users who’ve also upgraded their reminders. Everyone who shares the list can create and edit reminders from any computer or device set up with iCloud. Notifications aren’t shared; you can set a reminder to remind you at a time or place, but it won’t remind anyone else.
After you start sharing a reminder list, you can add or remove people, or stop sharing the list with anyone.
You can also assign reminders to people who share the list. See Assign shared reminders in Reminders on Mac.
Note: All Reminders features described in this guide are available when using upgraded iCloud reminders. Some features aren’t available when using accounts from other providers.
Share a list
In the Reminders app
on your Mac, select a reminder list in the sidebar, then click the Share button 
.The Share button appears only when the pointer is over the list or after the list is shared.
Select or unselect the “Anyone can add more people” tick box, depending on whether you want to allow people you add to the list to share it with others.
In the Share List window, choose how you’d like to send your invitation:
Send invitation using Mail or Messages: Click Mail or Messages, click Share, enter the people you want to share the list with, then click Send.
Send invitation using a link or AirDrop: Click Copy Link or AirDrop, enter addresses or phone numbers of the people you want to share the list with, then click Share.
The invitee must accept the invitation in order to view and edit the shared list.
Add people to a shared list
After you start sharing a reminder list, you can add more people who can see the list.
In the Reminders app
on your Mac, select a reminder list in the sidebar, then click the Share button .Select or unselect the “Anyone can add more people” tick box, depending on whether you want to allow people you add to the list to share it with others.
In the People window, click Add People.
In the Share List window, choose how you’d like to send your invitation:
Send invitation using Mail or Messages: Click Mail or Messages, click Share, enter the people you want to share the list with, then click Send.
Send invitation using a link or AirDrop: Click Copy Link or AirDrop, enter addresses or phone numbers of the people you want to share the list with, then click Share.
Change who can share the list with others
In the Reminders app
on your Mac, select a reminder list in the sidebar, then click the Share button .In the People window, do any of the following:
Allow everybody or nobody to add other people: Select or unselect the “Anyone can add people” tick box. This setting applies to every list participant except the list owner.
Allow specific individuals to add other people: Select a person in the list, click the Options button
on the right, then choose Allow to Add Other People so that a tick appears next to the option.Don’t allow specific individuals to add other people: Select a person in the list, click the Options button
on the right, then choose Allow to Add Other People so that the tick disappears.
Click Done.
Remove people from a shared list
If you no longer want to share a list with a person, you can remove them from the shared list.
In the Reminders app
on your Mac, select a reminder list in the sidebar, then click the Share button .In the People window, select the person you want to remove.
Click the Options button
at the right, then choose Remove Access.Click Done.
When you remove a person from the shared list, the list is removed from all of the other person’s devices.
Stop sharing a list
If you change your mind about sharing a list or no longer need to share it, you can stop sharing it with everyone.
In the Reminders app
on your Mac, select a reminder list in the sidebar, then click the Share button .In the People window, click Stop Sharing, then click Continue.
When you stop sharing a list, the list is removed from all participants’ devices.