Transfer Apple Mail to a PST file

Switching from Mac to a Windows work environment and my years of Apple Mail need to arrive as a PST for Outlook.

Apple Mail exports something but certainly not PST. What is the chain?

Two link chain: Apple Mail exports mbox natively and mbox converts to PST on the Windows side. Clean and lossless when done in order.

1

In Apple Mail select a mailbox in the sidebar, then Mailbox, Export Mailbox and choose a destination folder. Repeat per mailbox, each export produces a .mbox package containing the messages. Select multiple mailboxes with Cmd+click to export them in one pass.

2

Move the exported .mbox items to the Windows machine, external drive or network share, they are ordinary folders underneath.

3

Convert with an MBOX to PST converter, SysTools MBOX Converter accepts the Apple Mail .mbox exports directly and writes a PST with one folder per mailbox, attachments embedded as normal.

4

In Outlook attach the result via File, Open and Export, Open Outlook Data File, then drag folders into the live mailbox or keep the PST as a standing archive.

Only accounts and local On My Mac mailboxes need this treatment when the account is dying with the Mac. Anything living on IMAP or iCloud can skip the export entirely, add the same account to Windows Outlook and the server re-delivers it. Sort your sidebar into those two piles first and the export list often shrinks pleasantly.

Sorted the sidebar first as suggested, only 6 local mailboxes actually needed converting, the rest synced themselves. PST attached and the Mac era is archived.