Set up Working Hours in O365 Calendar (Two Ways)

Hours in O365 Calendar

You might think you have working hours in O365 Calendar are set up properly, but something is not right. Users are noticing that when they book appointments in a shared calendar or their own, the working hours for the organization do not match what is in the calendar. There are two places to check for this depending on which type of calendar you are booking in. Let’s go through the ways.

Set Working Hours in Your Own Calendar

This is set locally in your Outlook client and can be accessed by going to File / Options / Calendar and changing the Working Hours to your Organizations start and end time:

Hours in O365 Calendar

It is a good idea to make sure you have the proper time zone chosen as well:

Hours in O365 Calendar

If you are using the webmail version of Outlook, go to Settings (Gear Icon) and then view all settings at the bottom and change the working hours and time zone here:

Hours in O365 Calendar

Set Working Hours in a Shared Calendar

To accomplish this, you need to be an admin in O365. It requires some PowerShell commands. If you have a lot of shared calendars you need to change, you will want to use a for each loop to cycle through them all.

Use this command to ensure your calendars have the right working hours and are operating in the correct time zone:


Set-MailboxCalendarConfiguration -Identity <UPN> -WorkingHoursTimeZone "Eastern Standard Time" -WorkingHoursStartTime 08:00:00 -WorkingHoursEndTime 17:00:00

If you need configure many calendars, use a PowerShell Script:

## Declare Variables

$CSVPath = "FilePathHere\SharedCal.csv"

##Try import UPN CSV file

try {
    $SharedCals = import-csv $CSVPath -ErrorAction stop
catch {
    throw "Error importing CSV: $($_.Exception.Message)"

foreach ($SharedCal in $SharedCals) {

Set-MailboxCalendarConfiguration -Identity $SharedCal.calname -WorkingHoursTimeZone "Eastern Standard Time" -WorkingHoursStartTime 08:00:00 -WorkingHoursEndTime 17:00:00


In this case, when a user wants to book into a shared calendar, they will only see the work hours as free (white space). They can book outside of the available working hours they just can’t see it until after they book.

If you follow these two ways to adjust Working Hours in O365 calendar, you will have absolutely no problem scheduling meetings!

Happy IT’ing


Avatar photo

I am an IT professional with over twenty years experience in the field. I have supported thousands of users over the years. The organizations I have worked for range in size from one person to hundreds of people. I have performed support from Help Desk, Network / Cloud Administration, Network Support, Application Support, Implementation and Security.

Pin It on Pinterest