If you are using up most of your mailbox quota, Microsoft 365's In-Place/Online Archive is a good way of cleaning up your mailbox while still retaining messages.
The In-Place/Online Archive feature is available upon request. It is not turned on by default.
Request an In-Place/Online Archive
This archive only functions on Outlook desktop clients and Outlook for the Web. Those using Apple Mail, Thunderbird or any other mail client will be unable to see or access their archive.
The In-Place/Online Archive is currently not available on Outlook Mobile apps.
You can import your local archive (pst file) in to your In-Place/Online Archive. Please refer to the KB article Import Archived Mail from a PST File.
Unfortunately, Outlook for the Mac does not support importing into the In-Place/Online Archive. The only supported method is to move individual messages to your archive mailbox one by one (you can't move or copy multiple items at once). For additional information, please refer to the Microsoft Support article Use your online archive with Outlook for Mac.
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