Importing Apple Mail mboxes to non-Apple Mail

I may soon need to transfer some responsibilities in a volunteer organization to others. Much of the documentation for the jobs I am doing is contained in email threads in specific mail folders. I know that I can export these Apple Mail folders to mbox format, and the resulting mbox files should be easily importable to another account maintained via Apple Mail.

However, the folks who may need to reference these may not be using Apple Mail or even a Mac. So, how complex is it to import email exported from Apple Mail into other email systems such as Gmail, Outlook, etc via Macs or PCs?

It is not too bad, but, when possible, I avoid this path as follows:

  • Launch Apple mail
  • Configure the original iCloud mail account (if not already there
  • Configure the new Gmail or whatever account
  • After finishing configuration, simply drag and drop any or all source mailboxes, including any On My Mac mailboxes, to the new account.

You are done. Clean up as needed.