[Update]: This blog post was updated on March 6, 2020.

Want to improve cooperation in your organization? Calendar sharing might help you with just that. You can share a calendar in Office 365 by following at least three methods. The first one is sharing a calendar in Outlook on the web (OWA), the second one is sharing a calendar in Outlook, and the third method is creating a shared mailbox with access to shared calendar. In this blog post, you'll find instructions for all these methods.

Share an Office 365 calendar in Outlook on the web

To share a calendar in Outlook on the web (OWA), you need to:

  1. Open a calendar that you want to share with other users in your Office 365 organization. You can access it from the main menu in Outlook on the web (you might need to click All apps to see the Calendar option):
    Calendar app
    or by clicking the calendar icon at the bottom of the left pane:
    Calendar icon in Outlook
  2. From the My calendars list, select a calendar you want to share.
    My calendars
  3. When you hover over the chosen calendar, three dots will show up next to its name. Click the dots and then Sharing and permissions.
    Sharing and permissions
  4. Now, you can select individuals you want to share the calendar with. You need to add them one by one.
    Select people to your share calendar with
  5. You can set up access rights for each person separately. This way you decide what people can do with your shared calendar. To confirm the setup and start sharing the calendar, click Share.
    Access settings
  6. The selected person will show up on the list below. At any time, you can change the access rights for a selected person or remove them from the sharing list by clicking the trash bin icon.
    List of users with calendar access
  7. Once you click the Share button, the person you specified receives an email where they can accept your calendar sharing invitation by clicking the Add this calendar button.
    Accept sharing invitation
  8. After that, the email recipient can view the shared calendar by clicking the View calendar button.
    View calendar
  9. When they go the Calendar view, the shared calendar should be displayed there along with their other calendars.
    View a shared calendar

Share an Office 365 calendar in Outlook 2019 and 2016

To share your calendar in Outlook 2019 or 2016, follow the steps below:

  1. First, open Outlook, then from the left pane select a calendar you want to share or click the calendar icon on the bottom menu.
    Calendars in Outlook
  2. In the Calendar view, go to the Home menu and under the Share group, click Share Calendar.
    Shared calendar icon in Outlook
  3. In the Sharing invitation window, select users you want to share the calendar with. If you want the users to be able to add, edit and delete items in your calendar, make sure to select this option as well. In the section at the bottom, you can put some comments, if needed. Click Send once the invitation is ready.
    Calendar event

Create a shared calendar in Office 365

To create a shared calendar in Office 365 you need to create a shared mailbox and assign full access permissions to users who will use its calendar. The calendar that comes along with this shared mailbox will become the shared calendar for the selected users.

Follow the steps below to create a shared calendar in Office 365:

Create a shared mailbox in Office 365

  1. Log in to your Office 365 portal with your admin credentials and click the Admin app to access Microsoft 365 admin center.
    Admin app in Office 365
  2. In Microsoft 365 admin center, under the Admin centers section, select Exchange.
    Exchange in Admin centers
  3. In the Exchange admin center, go to recipients, and shared.
    Creating a shared mailbox
  4. Click the plus icon (+) to add a new shared mailbox.
  5. Provide the name for your shared mailbox, enter an email address and add users that will have permissions to use this shared mailbox.

    Note: Instead of adding individual users one by one, you may want to create a security group first and then add this security group to the shared mailbox. This is useful when you need to manage permissions for many users in the organization.
    New shared mailbox

  6. Click Save to create the shared mailbox.
  7. The new shared mailbox should appear on the shared list. Double-click it to edit its settings.
  8. In the mailbox delegation tab, make sure the selected users (or a security group) have Full Access permissions assigned to this mailbox. Click Save to finish creating the mailbox.

    Note: Full Access permissions will allow the users to add, edit and delete calendar entries in the shared calendar. Users that have no permissions to this shared mailbox will only be able to see the Free/Busy statuses.
    Shared mailbox delegation

Using the shared calendar in Outlook

When you have finished creating the shared mailbox, you can start using its calendar as a shared calendar. Check if you can see it in your Outlook. It should appear automatically under My Calendars.

Using the shared calendar in OWA

To display and start using the shared calendar in Outlook on the web (OWA) you need to open it from a directory. To do that:

  1. Go to the calendar view. You can access it from the bottom menu in the left pane in Outlook on the web by clicking the Calendar icon.
    Calendar icon in Outlook
  2. Click Add calendar.
    Add shared calendar in OWA
  3. Select Add from directory and search for your shared calendar by typing the name of the shared mailbox.
    Add shared calendar from directory
  4. In the Add to section, choose where the calendar should be added to and click Add.
    Select destination for a shared calendar in OWA
  5. The shared calendar should appear on the calendar list.
    Shared calendar opened in OWA

Note: The test environment I used for this guide is Microsoft 365 E5 suite. In other plans the steps and screenshots may look a bit different.

How to stop sharing calendars in Office 365?

If you no longer want to share your calendar, you can either remove the calendar from sharing (Outlook on the web) or remove calendar permissions (Outlook 2019 and 2016).

To stop sharing your calendar in Outlook on the web:

  1. Go to Step 6 from the instruction above.
  2. Click the trash bin icon to remove the users from the sharing list.
    Removing users from the calendar sharing list.

Stop sharing your calendar in Outlook 2019 or 2016

Follow the steps below to stop sharing your Office 365 calendar in Outlook 2019 or 2016:

  1. In the Calendar view, go to Home menu and under the Share group, click Calendar Permissions.
  2. In the Calendar Permissions window, go to the Permissions tab and select users you want to remove from sharing. Click Remove, then Apply, and OK.
    Permissions to a calendar

That's it. These two simple methods allow you to share a calendar in Office 365 by using the native options built in Outlook on the web and Outlook 2019/2016.

See also:

  • Contacts sharing in Office 365
  • How to prevent Office 365 users from sending emails outside the organization?
  • MailTips in Office 365
Tools for Exchange Server