Dear jilliangran
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
- Based on your description, we did a test on our end, go to System Preferences --> Language and Region --> Advanced --> Dates, and
it shows four types of date format as the screenshot below:
If you want to set Excel to default to a date format of 1/1/22, you can Type in or click and drag elements to format your "Short" date
- If you set the correct steps but the date format still can't work, please make sure your Excel and your Mac have updated to the latest version, sometimes, the update will also caused unexpected behavior.
- For Excel: Click Excel icon> Help> Check for Updates>Click Update to download and install all the available updates.
- For Mac: the latest update version for macOS Monterey is version 12.4, see Update macOS on Mac - Apple Support
- Besides, since the default formats used by Excel for Dates, Times & Numbers is determined by the macOS System Preferences for Language & Region. You must restart the program in order for the changes to go into effect after you set this in Date page. Here is a similiar thread, you can have a reference: How do I change the default date format on Excel for Mac to - Microsoft Community
- Meanwhile, we would like to collect more detailed information about the situation you are experiencing so that we can have further investigation:
- Can you give us a screenshot that your full Date page to us like the pictute below?
- Please also give us a screenshot of your Excel and Mac version.
- For Excel: click Excel>About Excel
- For Mac: Click the Apple icon>Abot the Mac
We’re looking forward to your reply and will continue to help you all the time! If there are any misunderstanding or unclear, You can post back in your free time.
Sincerely,
Stacey | Microsoft Community Moderator
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