In macOS 10.13 and later, this article describes how to save Apple Mail emails to a single text file.
Save Multiple Emails in a Single File
To save multiple messages from Mail to a single consolidated text file:
- Navigate to the folder that contains the messages you wish to save.
- Select the emails you wish to save to a single file by highlighting them.
- While holding Shift, click a contiguous region.
- While holding down Command, select multiple emails.
- Additionally, you can combine these two methods.
- From the menu, choose File > Save As.
- Under Save As, type a file name that is different from the subject line of the first selected messages.
- Under Where, select a folder for saving.
- Under Format, choose either Rich Text Format (completely formatted email text) or Plain Text (plain text versions of email messages).
- Click Save.
The text file contains the sender, subject, and recipients of the messages as they appear in Mail when you read them.