A master calender is a common request for team sites that have sub-sites. If you are running SharePoint 2010, there’s now a built-in way to do a roll-up master calendar using the calendar overlay feature.
The Steps
- At the site on which you want to display the master calendar, either create a calendar list or use the existing team site calendar.
- On the Calendar tab in the ribbon, click Calendars Overlay.
- Click the New Calendar link to add a new calendar.
- In the next screen, you will need to provide information about the calendar you are adding (name, description, etc.) plus the URL of the site that houses the calendar. *(Note that the URL should be to the site, not to the calendar itself. SharePoint will find all the possible lists and views once you click the Resolve button after entering the URL address.) If the site has multiple calendar lists or views, you will need to select the one you wish to overlay from the drop down boxes. Check the box next to Always Show. Click OK.
- Repeat Steps 3-4 for each calendar you wish to add.
- When all the calendars are added, click “Ok.”
- Now all the calendars will show on the main calendar.
The Caveats
You knew there were some, right?
- You can only include 10 calendars.
- You only have 8 colors to choose from.
- You can include calendars that are above the site of the “master calendar” and that are siblings to the master calendar, and even that aren’t in the same site collection (Yay!). But, if the person visiting the site doesn’t have permissions to view the other calendar, you’ll get this error:
Oops. So, be careful with permissions on your overlays.
- If you connect to Outlook on the main calendar, it will not include the overlaid calendars.
- If you add a web part of the master calendar to a page, it will not include the overlaid items you have to switch to “calendar” view in the web part properties to see the overlaid items.
- You can overlay lists that are not of the calendar type, as long as they have a calendar view. (This isn’t really a caveat – just a good thing to note.)
You can also overlay Exchange calendars. Sharad Kumar has a good blog post on how to aggregate Exchange Appointments into a Calendar View.






Andrew Brooks
/ November 2, 2011When I try and overlay Exhcnage Calendars, I get my own calendar, with no detail of the event, just “Busy”, and additional calendars I try to overlay I jsut get a replication of my calendar, with no detail! Suspect it is a permissions thing, as both OWA and Exchange Web Services seem to be working correctly? Any ideas? I can’t believe there isn’t an answer to this anywhere else either!
Deanna
/ November 2, 2011I’m not sure. I haven’t played much with overlaying Exchange Calendars. I suspect you’re correct in that it’s a permissions issue. When I try to overlay an Exchange calendar in my environment, I get an error about establishing a trust relationship. I think I know the problem there (see this blog post: http://blog.mattsampson.net/index.php/calling-a-webservice-over-ssl-in-sharepoint-ssl?blog=1). But, it’s not something I have the capacity to mess with at this point. So, can’t be of much help. Sorry!
Nidhi
/ March 30, 2012Great article Deanna! Just a correction: The caveat no. 5 is not true. All you have to do is Edit the web part properties and select “Calendar” View in the Views drop-down. Then, the calendar webpart will show the overlaid items. Try it out!
Deanna
/ March 30, 2012Hey good catch! Thanks for that. I updated the article to reflect that bit of info. Sometimes it’s the simplest things that we miss, right?
Robert
/ August 27, 2012For those who have the issue of having duplicate calendar entry issues, as I was, it is important to filter your page. All overlays will have a filter that looks something like “Category” “is equal to” “Red” (if using colors (and where Category is the selection column)). But on your page you may see the event in red and the duplicate event in the default colors. If you find this, simply go to your main view and filter “Category” “is equal to” “” (that’s right, leave it blank). Now you will only see the overlay.
Sorry if this doesn’t quite fit with this page, but this took me hours to figure out and there was no place on the internet with this solution.
Kevin Nguyen
/ November 8, 2012This is definitely good stuff….
Philippe Stuyts
/ December 14, 2012I wonder if it is possible to create 2 filtered views on the same calendar and publish them in overlay mode with different colors. We are implementing a change calendar and it would be great to have approved changes appear in green and non approved in red.
thank you.
Deanna
/ December 14, 2012I’m not sure, but you can always try.
Philippe Stuyts
/ December 14, 2012As far as I could go, I can only put different calendars in overlay mode. But I can’t find a way to select a view in stead of another calendar.