High CPU Usage By Outlook for Mac in MacOS Catalina

Question

I've been having lots of issues with Apple's MAIL program with high cpu usage in macOS Catalina on a new 16 inch MacBook Pro and the issue appears to be a known issue that MAIL has communicating with Exchange accounts.  So while it is being addressed I have moved to Outlook for Mac as part of my Office365 subscription.  But Outlook for Mac is taking 9-10 gb or RAM in Activity Monitor on a consistent basis and I want to know if this is normal and if not, how it can be reduced.  Performance in Outlook is being affected due to the high memory usage.  Anyone else experiencing this and for any that have, suggestions on how to reduce the RAM grab?

Moved from Outlook  / Mac  / Office 2016 for Mac

Answer 1

Hi DocEames,

Thanks for your post. About the issue that Outlook is using high CPU issue, please firstly verify that you don't have any third-party plugins that are running and interacting with Outlook. If so, please quit (or uninstall) the plugin and restart Outlook.

In the meantime, to isolate whether this issue is caused by any background programs, please start your Mac in safe mode and only open Outlook for mac to check the result. 

Moreover, make sure to update both your Mac OS and Outlook client to the latest version and see if this will make any improvement.

To help you better and further, we highly recommended to to contact our OUtlook for Mac experts to get for further target suggestions, which is our dedicated support channel that will keep working on the problem with you. Open Outlook for Mac and go to Help > Contact support.

Thank you for your understanding and cooperation.

Regards,

Jennifer

Answer 2

I've been having lots of issues with Apple's MAIL program with high cpu usage in macOS Catalina on a new 16 inch MacBook Pro and the issue appears to be a known issue that MAIL has communicating with Exchange accounts.  So while it is being addressed I have moved to Outlook for Mac as part of my Office365 subscription.  But Outlook for Mac is taking 9-10 gb or RAM in Activity Monitor on a consistent basis and I want to know if this is normal and if not, how it can be reduced.  Performance in Outlook is being affected due to the high memory usage.  Anyone else experiencing this and for any that have, suggestions on how to reduce the RAM grab?

Moved from Outlook  / Mac  / Office 2016 for Mac

Same problem with Outlook in Office 365 for Mac. Simple solution: reinstall Outlook from the App Store. Worked like a charm.

Answer 3

Hey,

I've followed the advice of a pro: close Outlook, then reopen while holding down the option and command keys at the same time and my CPU usage went down to 4% straight away from 150%.

Hope it helps!

(I was using a MacBook Air 2020.)

Answer 4

I've switched to 'fast insider' which so far - couple of hours - seems to have made a significant difference to CPU usage by Outlook. This is the 'new Outlook' introduced in late 2019 which is a complete change of architecture. Generally a better product so strongly recommend.

Prior to this move Outlook dominated the CPU usage and drove excessive fan use and noise.

Answer 5

I've been having lots of issues with Apple's MAIL program with high cpu usage in macOS Catalina on a new 16 inch MacBook Pro and the issue appears to be a known issue that MAIL has communicating with Exchange accounts.  So while it is being addressed I have moved to Outlook for Mac as part of my Office365 subscription.  But Outlook for Mac is taking 9-10 gb or RAM in Activity Monitor on a consistent basis and I want to know if this is normal and if not, how it can be reduced.  Performance in Outlook is being affected due to the high memory usage.  Anyone else experiencing this and for any that have, suggestions on how to reduce the RAM grab?

Moved from Outlook  / Mac  / Office 2016 for Mac

Im having the same issue with a Mac book Pro i9 16G ram 2019 model. outlook takes up 33% to 50% of my cpu all of the time . I just installed office 360 from the MS web site yesterday I have Catalina and it was updated after the office 360 install.  I'm new to Mac so please excuse my lack of knowledge on Mac.  I uninstalled the office 360 and reinstalled it and waited about 30 minutes and the usage dropped to below chrome cpu usage 1 to 2 % . Go figure ?