How to Transfer Outlook from Mac to Windows Operating System?

Want to transfer Outlook from Mac to Windows without losing a single email? Good news: for most people, it’s easier than it used to be. The catch is that the two apps store local mail in different file types. Mac Outlook uses OLM, Windows Outlook uses PST, and they don’t talk to each other.

This guide covers the three methods that still work in 2026, which one fits your setup, and the deadline Mac users can’t ignore this month.

First, Check Where Your Mail Actually Lives

This one question will determine your entire path. Open Outlook on your Mac and look at the list of folders.

• Microsoft 365, Outlook.com, Exchange or Gmail account: your mail is stored in the cloud. Go to Method 1.
• If your message folders say “On My Computer” or you have an old POP account: your mail is stored solely on the Mac. You’ll need Method 2 or 3.

In my experience, most people freak out about file conversion even though their email is already sitting comfortably on a server.

Your situation	Best method	Moves email	Moves contacts and calendar	Cost
Cloud account (Microsoft 365, Outlook.com, Gmail)	Sign in on Windows	Yes	Yes	Free
Local folders, Mac still available	IMAP bridge	Yes	No	Free
Only have an OLM file	OLM to PST converter	Yes	Yes	Usually paid

Heads-Up: Legacy Outlook for Mac Is Going Away

If you’re still using the legacy Outlook interface on your Mac, act quickly. Microsoft’s end-of-support notice for legacy Outlook for Mac confirms that starting October 2026, legacy Outlook stops working with Exchange Online mailboxes.

Why does this matter? Because the .olm export lives in legacy Outlook. The new Outlook for Mac doesn’t offer the same import and export tools. Export your local folders while you still can.

Method 1: Sign In on Windows (Cloud Accounts)

Here’s the cheat code. Because your mail lives on a server, nothing has to be converted.

1. Install Outlook on your Windows computer.
2. Use the same email account that you used on the Mac.
3. Your email, contacts, and calendar will now begin to sync.

That’s all. I noticed a big mailbox can take a few hours to fully sync, so leave your PC on overnight.

Method 2: Use an IMAP Account as a Bridge (Free)

Already have local folders and both machines? Set up an IMAP account such as Gmail as a go-between. The original version of this guide listed this method, and it still works.

1. Set up an IMAP email account in Outlook for Mac.
2. Make a folder within that IMAP account.
3. Drag your “On My Computer” folders into it.
4. Wait until the sync finishes. Check the account online to confirm it’s all there.
5. Add the identical IMAP account to Outlook on Windows.
6. Drag the folders to your Windows mailbox.

Where the IMAP Method Falls Short

• Email only. IMAP does not move contacts, calendars, and tasks.
• Sluggish with large mailboxes. Thousands of messages can take hours to upload.
• Storage limits. If you have a free Gmail account, you only get 15 GB of storage (this is shared with Drive and Photos).

When I’ve used this route, attachments took up most of the upload time, not the number of messages.

Method 3: Convert OLM to PST (No Mac Needed)

You cannot open the OLM file in Windows Outlook. When you attempt to open it, you’ll see an error saying the file isn’t an Outlook data file. Microsoft’s own support article on OLM files confirms that Windows Outlook doesn’t support the format, and Microsoft doesn’t offer an OLM-to-PST converter.

So you’ll need a third-party tool. Export your mailbox from legacy Outlook for Mac (File or Tools > Export > Outlook for Mac Data File), then process it using a converter such as Corbett OLM Converter:

1. Download the converter and run it on your Windows PC.
2. Browse to your OLM file and add it.
3. Select PST as the export type.
4. Choose a folder to save the output to and select Export.
5. In Windows Outlook, go to File > Open & Export > Import/Export, and import the PST.

What Should I Look For in a Converter?

Feature	Why it matters
Keeps folder structure	You don’t want 10,000 emails dumped into one folder
Converts contacts and calendars	Covers what IMAP can’t
Date, sender or subject filters	Moves only what you need
Works without Outlook installed	Handy for checking the file first
Free trial	Lets you test on a few items before paying

My advice: test the free trial on a small folder first, and check that dates, attachments and folder names come through clean before you pay.

Why People Move Outlook From Mac to Windows

• Changing jobs or computers: Going from MacBook to a Windows laptop
• Obtaining an OLM file from a client or previous coworker
• Sharing archived mail with a team that uses Windows Outlook

Microsoft’s Mac and Windows apps are clear doppelgangers, and both pieces of software are ideal for daily email. The file formats are the only true barrier between them.

My Verdict: Which Method to Pick

If your mail is in the cloud, log in on Windows, and that’s it. If you have local folders and both machines, the IMAP bridge is free but only moves email. If all you have is an OLM file, a converter is the most elegant solution. No matter which path you choose, export from legacy Outlook for Mac before support runs out.

Is there a step you’re stuck on? Leave your question in the comments.

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Related: Mac Users: 7 Key Things Every New Mac Owner Should Know