Can I set a default Meeting Duration for all users in my M365 tenant?

You can shorten meeting globally, but you cant set a default meeting time. Meetings owners can override this:

https://office365itpros.com/2021/04/22/shorten-outlook-meetings/

Hi @Keithboatner,

Welcome to Microsoft Q&A, and thank you very much for reaching out to us.

Based on your description, may I confirm that you're referring to setting the default meeting duration in Classic Outlook? Please feel free to correct me if I misunderstood.

Based on my research, there is currently no centralized setting available in Classic Outlook or Exchange that allows administrators to set a default meeting duration for all users. The closest option is within Classic Outlook’s Calendar Options, where individual users can configure their own default meeting duration.

However, this is a client-side setting only and does not apply organization-wide.

That said, I completely understand how valuable such a feature would be. I highly recommend submitting this request through the Microsoft Feedback portal. The more voices that support this idea, the more likely it is that Microsoft engineers will consider implementing it in future updates.

Thank you very much for your time. If you have any questions or need further clarification, please don’t hesitate to let me know. I’d be happy to assist you further.

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