Save messages as files or PDFs
You can save messages as files to use in other apps, as PDFs, or in mbox format (for importing into Mail or most other email apps).
Save messages as files: Select one or more messages or conversations, then choose File > Save As.
Rich Text Format retains formatting (such as bold and italics), but Plain Text does not. Raw Message Source saves messages in mbox format; the header is visible and an encoded version of attachments is retained.
Save messages as PDFs: Select one or more messages, then choose File > Export as PDF.
Save a single message in mbox format: Drag the message to your desktop. To reopen the message in Mail, double-click the file.