Dear Brett Johnson1,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
From your description It seems you want to know how to Calendar Overlays for SharePoint.
Unfortunately you cannot create a calendar view in a custom list and overlay it on a Calendar. You can only overlay lists created using Events/Calendar list templates. Calendar view on a custom list just creates a Calendar UI but it is not an Events/Calendar list in the backend and cannot be treated as one
As a work around you can use SharePoint Calendar Overlay
SharePoint Online: Calendar Overlay limit Please note, the calendar overlay feature in SharePoint Online doesn’t support different site collections.
To configure a calendar overlay, do the following:
- Navigate to the calendar list on the top of which you want to overlay other calendar events.
- On the calendar view page, click on the Calendar ribbon tab >> Click on the “Calendars Overlay” button.
. https://www.sharepointdiary.com/wp-content/uploads/2019/01/calendar-overlay-in-sharepoint-online.png
- This opens the Calendar Overlay Settings Page. Click the “New Calendar” link to add a calendar to the list of additional calendars.
- Enter the Name of the calendar and select the type of calendar as SharePoint.
- Set the color to be used for items from the selected calendar.
- In the URL field, By default, your current Web URL will appear, click the Resolve button to populate the List drop-down with available Calendars from this site and select the desired calendar. Specify whether the overlay is always to be included on the calendar. If it’s not selected, users viewing the list can remove the overlay.
- Once all information is entered, click the OK button. You will now see your calendar listed under Additional Calendars, Click OK.
Now you’ll see all the data from both calendars in a single calendar view. Based on your calendar overlay additions and visibility settings,

Your understanding and patience will be highly appreciated.
If there is any misunderstanding, please feel free to correct me.
Have a nice day!
Best regards,
