Working with time zones is always difficult. Not only in SharePoint or Microsoft 365, but probably in any platform or application. In this post I want to overview how Outlook and SharePoint events dates are displayed in different Microsoft 365 applications based on different configurations available to the user.

SharePoint Events

Let's start with SharePoint events.
There are 2 configurations that affect on how the event date/time is displayed to the user. Or, to be more specific, in what time zone the event date will be displayed.
The first configuration is Site Regional Settings that you can access in Site Settings -> Regional Settings:
Site Regional Settings
In most cases, this is the only configuration set, and all users see events in the same time zone.
But user can additionally set regional settings for himself. This is done in user's Office Profile (Delve). Here you can find the documentation how to change the settings. Here is the screenshot of the documentation:
Office profile
If this configuration is set, a user will see the events dates in the same time zone on any SharePoint site.
Good thing about SharePoint events - they will be displayed in the same time zone/format both in SharePoint and Microsoft Teams. So, the only possible confusion is where this time zone configuration comes from :)

Outlook Events

Now Outlook events.
Outlook events are displayed based on the time zone set in user's Microsoft Account that can be accessed using https://myaccount.microsoft.com url.
Single configuration, pretty easy, right?..
But...
First, Microsoft Account IS NOT EQUAL to Office Profile. It means if you have an app that synchronizes Outlook and SharePoint events, users can see different dates/times in SharePoint and Outlook based on their configurations in Microsoft Account and Office Profile.
Second, if you look at the event in Microsoft Teams Calendar, you will see the event in the current time zone - the time zone of your machine, which can be confusing.

Conclusion

Below is an example for the event that is happening on October 21, 2020 5:00 PM UTC-8.
My machine's time zone is UTC-8, Office Profile time zone is set to UTC, and Microsoft Account time zone is set to UTC+10:
Different configurations
And here is a small summary table for the configurations and display results:

Source Possible Configurations Time Zone in SP Time Zone in Outlook Time Zone in Teams
Outlook Microsoft Account N/A Set in Microsoft Account Current machine's time zone
SharePoint Site Regional Settings
Office Profile		 Office Profile time zone, if set; Site time zone otherwise N/A Office Profile time zone, if set; Site time zone otherwise

Hope, this information helps you and your users to resolve the confusions.

That's all for today!
Have fun!