To find out the version of Outlook you’re using, follow the steps below for the desktop and mobile apps.
Checking the Outlook Version on Desktop
- Launch the Outlook desktop app and click on File.
Select File. - Select Office Account on the left sidebar.
Go to the Office Account tab. - Under “About Outlook” on the right, you will see the version number.
Check out the version number under About Outlook. - To learn more information about the app version, click on About Outlook.
Click About Outlook. 
New window showing more details about the Outlook app.
Checking the Outlook App Version on Mobile
- Launch the Outlook app and tap on your profile icon on the top-left.
Click on your profile icon. - Tap on Settings in the bottom-left.
Select the Settings icon. - Tap on Help & feedback.
Select Help & feedback. - Scroll to the bottom of the screen to find the version number.
Scroll to the bottom of the screen and look for the version number.