When you share your Outlook calendar with a colleague, you must assign a permission level that controls what they can see and do. The three most common levels are Reviewer, Author, and Editor. Each grants a different combination of read, write, and delete access to calendar items. This article explains exactly what each permission level allows, how to assign them, and how to avoid common mistakes when sharing your calendar.
Key Takeaways: Outlook Calendar Permission Levels
- Reviewer permission: Read-only access to free/busy, title, location, and details. Cannot create, edit, or delete items.
- Author permission: Read and create items. Can edit and delete only their own items. Cannot modify items created by the calendar owner.
- Editor permission: Full read, create, edit, and delete access to all items on the calendar. Same rights as the owner except for changing permissions.
What Each Outlook Calendar Permission Level Does
Outlook calendar sharing uses a permission system inherited from Exchange Server and Microsoft 365. Each permission level is a predefined set of rights that controls how a delegate or a shared-calendar user can interact with calendar items. The three most common levels are Reviewer, Author, and Editor. A fourth level, Contributor, exists but is rarely used for calendars because it only allows item creation without read access.
The permission model applies to both on-premises Exchange mailboxes and Microsoft 365 cloud mailboxes. The behavior is identical in Outlook for Windows, Outlook for Mac, Outlook on the web, and the Outlook mobile app. The calendar owner assigns these permissions through the Calendar Properties dialog or through Exchange Admin Center for bulk assignments.
Reviewer Permission
Reviewer is the most restrictive sharing level. A user with Reviewer permission can view all calendar items, including the subject, location, start and end times, and any notes or attachments in the body. They cannot create new appointments or meetings, edit existing items, or delete anything. This level is ideal for assistants who only need to know your schedule without making changes.
Author Permission
Author permission adds create and self-edit capabilities. A user with Author rights can create new appointments and meetings on the calendar. They can edit and delete only the items they created. They cannot modify or remove items created by the calendar owner or by other delegates. This level suits team members who schedule meetings on behalf of a shared resource or a manager but must not alter existing entries.
Editor Permission
Editor permission grants full control over calendar content. An Editor can create, read, edit, and delete any item on the calendar, regardless of who created it. The only action an Editor cannot perform is changing the permission settings of the calendar itself. This level is appropriate for executive assistants who manage the entire calendar and need to update or remove any appointment.
How to Assign Calendar Permissions in Outlook
You can set permissions from within Outlook or through Exchange Admin Center. The following steps work for Outlook for Microsoft 365, Outlook 2021, 2019, and 2016. The process is the same for Windows and Mac versions with slight menu differences.
- Open Calendar Properties
In Outlook, go to the Calendar view. On the Home tab, click Calendar Permissions in the Share group. If you do not see this button, right-click the calendar name in the folder pane and select Properties. - Select the Permissions tab
In the Properties dialog, click the Permissions tab. The top section lists users who already have access. The bottom section shows the permission level for the selected user. - Add a user if needed
Click Add, type the name of the person or group in the Add Users dialog, click Add, then click OK. The new user appears in the list with a default permission level. - Choose the permission level
Select the user from the list. In the Permission Level drop-down, pick Reviewer, Author, or Editor. The individual checkboxes below update automatically to reflect the rights for that level. - Apply and close
Click Apply to save the change, then click OK to close the Properties dialog. The user receives an email notification that the calendar has been shared. They can now add your calendar to their Outlook by clicking File > Account Settings > Delegation Access or by right-clicking Calendar and choosing Add Calendar > From Address Book.
Common Permission Mistakes and Limitations
Even experienced Outlook users make errors when setting calendar permissions. The following issues are the most frequent causes of confusion and access problems.
Delegate vs Shared Calendar Permissions
Outlook distinguishes between a delegate and a user with shared calendar access. A delegate receives send-on-behalf-of permission and can manage meeting requests and responses. A shared calendar user only sees the calendar content. If you assign Editor permission through Calendar Properties, the user can edit items but cannot send meeting requests on your behalf. To grant delegate rights, go to File > Account Settings > Delegate Access. Delegates automatically receive Editor-level calendar access plus meeting management.
Author Cannot See Private Items
By default, all permission levels except Editor cannot view items marked as Private. If you want an Author to see private appointments, you must check the box that says Delegate can see my private items in the Delegation dialog. This setting is separate from the permission level and is not available in the Calendar Properties dialog.
Permission Changes Do Not Apply Immediately
When you change a permission level, the update may take up to 15 minutes to sync to Exchange Online or your on-premises Exchange server. The user may need to close and reopen the shared calendar or restart Outlook to see the new rights. To force a refresh, press F9 to send and receive all folders.
Reviewer Can Still See Meeting Attachments
Reviewer permission grants read access to the entire item body, including attachments. If you embed sensitive files in a calendar item, a Reviewer can open them. To prevent this, do not attach files to calendar items or use a different sharing method for confidential documents.
Reviewer vs Author vs Editor: Complete Feature Comparison
| Feature | Reviewer | Author | Editor |
|---|---|---|---|
| View item subject and details | Yes | Yes | Yes |
| View free/busy time only | No (sees full details) | No | No |
| Create new items | No | Yes | Yes |
| Edit own items | No | Yes | Yes |
| Edit items created by others | No | No | Yes |
| Delete own items | No | Yes | Yes |
| Delete items created by others | No | No | Yes |
| View private items | No (unless delegate setting allows) | No (unless delegate setting allows) | No (unless delegate setting allows) |
| Send meeting requests on your behalf | No | No | No (requires delegate assignment) |
| Change calendar permissions | No | No | No |
Now you can assign the correct Outlook calendar permission level based on what each user needs to do. For a team member who only checks your availability, use Reviewer. For someone who schedules meetings but should not touch existing entries, use Author. For a full calendar manager, use Editor. Remember that private items require an additional delegate setting regardless of the permission level.