Switch from Microsoft 365 Business to Outlook.com: step by step
How to move your mail, contacts and address from Microsoft 365 Business to Outlook.com without losing anything. Most moves take an evening to set up, then a few weeks of forwarding.
Watch out for
- Outlook.com doesn't let you use your own domain, so you can't take an address like you@yourname.co.uk with you.
Before you start
- Check where your address lives. Microsoft 365 Business runs on your own domain, like you@yourname.co.uk, so your address comes with you: you'll change a few DNS settings.
- Check the space you need. See how much mail you have in Microsoft 365 Business, and compare it with Outlook.com's plans (the cheapest is Free (Microsoft 365 Basic for more space), Free, with 15 GB).
- Read the small print. Outlook.com's page covers exporting, cancelling and refunds under "Before you sign up".
Open your Outlook.com account
Sign up on Outlook.com's website (Free), and turn on two-step sign-in straight away. You'll find the link on Outlook.com's page: Outlook.com.
Bring your mail across
Copy it with a mail app. Add both accounts to a mail app over IMAP (Thunderbird is free, for Windows, Mac and Linux), then drag your folders from Microsoft 365 Business to Outlook.com. It's slow for a big mailbox, but it works with almost any provider. Thunderbird ↗
Your old mail stays where it is while it's copied, so nothing is lost if you need to start again.
Move your contacts and calendar
Export your contacts as a .vcf file and each calendar as an .ics file from Microsoft 365 Business, then import them into Outlook.com. Most providers have both options in their contacts and calendar settings.
Check everything arrived
- Compare the number of emails in each folder on both sides.
- Send a test email to your new address from another account, and reply to it.
- Check that mail forwarded from Microsoft 365 Business is arriving, and isn't going to spam.
Close Microsoft 365 Business, when you're ready
Wait at least a month, until nothing new arrives there. On a free account you can leave it open with forwarding on instead. Before you close a paid account, download a last copy of your mail.
From Microsoft 365 Business's page: Microsoft 365 Business.
I checked the providers' help pages on 24 October 2026. Menus move, so if a step doesn't match what you see, tell me and I'll update it.
Moving to Outlook.com from somewhere else? Gmail to Outlook.com · iCloud Mail to Outlook.com · Proton Mail to Outlook.com · Fastmail to Outlook.com · Tuta to Outlook.com · mailbox.org to Outlook.com · All switching guides