How to convert EML to MBOX using Apple Mail
A number of people have asked this question and have been directed to install an app...but there's no need, since that capability is already built into Apple Mail.
- Open Apple Mail and optionally create a new folder "On My Mac" to hold it: Mailbox -> New Mailbox...
- In the Finder, open the .EML files using Apple Mail
- In the separate window that appears, select Move (for me, this was under >> on the right side of my toolbar, since the window that opened up wasn't apparently wide enough to show this item), then indicate whether you want to move the EML to an existing mailbox item (Inbox, etc) or the new folder you created
- Then right click on the container you want to convert to MBOX, and choose Export Mailbox (if you have subfolders that you want to export, be sure to select Export All Subfolders from the Options on that window)
- This creates a .MBOX folder (a container that the Finder doesn't know how to associate to an app, thus it appears as a folder)
- You can then import this .MBOX folder into another app that supports it, or zip it (in the Finder, right-click then choose Compress) and transfer it to its final destination.
Hope this helps someone - it took a fair bit of fiddling around for me to figure this out, since the top Google results were all for questionable converter apps.
Incidentally, you can also use Apple Mail to transfer emails from one account to another - providing you can get all the messages into Mail, you can then drag them over to whatever other accounts you have configured in Mail.
