Convert Outlook for Mac OLM to MBOX

Q: Will the mbox work with Apple Mail?

Yes. The output is standard mboxrd (one file per folder, >From lines escaped), which Apple Mail, Thunderbird and mutt read.

Convert an .olm archive into one .mbox file per Outlook folder (or .eml per email) to import into Apple Mail, Thunderbird or Gmail tools. Runs locally in your browser.

Open the converter Free for up to 25 emails per export · no sign-up

Leaving Outlook for Mac? Apple Mail and Thunderbird can't read .olm files, but both import .mbox. Mailtrail rebuilds standard MIME messages from the OLM's XML (headers, HTML and text bodies, attachments) and writes one mbox per folder.

How to do it

Open the converter in Chrome, Edge, Firefox or Safari. Nothing is installed and nothing is uploaded.
Drop the .olm file.
Under Output, tick .mbox per folder (and/or .eml per email). Untick the PDF options if you only want mail files.
Export. In the ZIP you'll find mbox/Inbox.mbox, mbox/Sent Items.mbox and so on.

Importing the result

Apple Mail: File → Import Mailboxes… → “Files in mbox format”, then select the extracted mbox folder.
Thunderbird: install the ImportExportTools NG add-on, right-click a local folder → ImportExportTools NG → Import mbox file.
Gmail: Gmail has no mbox import; import into Thunderbird with your Gmail account connected and drag folders across.

The rebuilt messages keep sender, recipients, date, subject, Message-ID, HTML/plain bodies and attachments. Outlook-only properties (categories, flags, read state) are not carried over.

What you get

One PDF per email with a header block (subject, from, to, cc, date, folder, attachment list) and the body, including embedded images. Searchable text, not screenshots.
Your folder structure mirrored in the ZIP, and file names that sort by date: Inbox/2024-03-05_0912 Jane Doe - Invoice March.pdf.
Attachments as original files under attachments/.
index.csv (date, from, to, cc, subject, folder, file names, attachment count, Message-ID, pages) and errors.csv for anything that couldn't be converted.
Optional: one merged PDF, .eml per email, .mbox per folder. Pro adds Bates numbering, page numbers, SHA-256 hashes and bookmarks.

Private by design

The conversion runs inside your browser tab with Web Workers. Your archive is never uploaded, and there is no server that could see it. You can even disconnect from the internet after the page loads. The only network call is the optional license-key check, which sends the key and a random device ID.

Questions

Will the mbox work with Apple Mail?

Yes. The output is standard mboxrd (one file per folder, >From lines escaped), which Apple Mail, Thunderbird and mutt read.

What does it cost?

Free for up to 25 emails per export. Standard ($29 one-time) removes the limit; Pro ($69 one-time) adds Bates numbering, page numbers, hashes and bookmarked merged PDFs. See pricing.