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Moving from Microsoft 365 Business: step by step

How to move your mail, contacts and address from Microsoft 365 Business without losing anything. Most moves take an evening to set up, then a few weeks of forwarding.

  1. 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.
    • Read the small print. Check your new provider's export, cancellation and refund rules before you pay.
  2. Open your your new provider account

    Sign up and set a strong password, with two-step sign-in turned on.

  3. 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 your new provider. 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.

  4. 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 your new provider. Most providers have both options in their contacts and calendar settings.

  5. If you use your own domain

    Your address moves with you. Do this after your mail has been copied:

    1. Add your domain in your new provider's settings, and create the same addresses there.
    2. A day before, lower the TTL on your domain's MX records (to 300 seconds, say), so the change takes effect quickly.
    3. Replace the MX records with your new provider's, and swap Microsoft 365 Business's entry in your SPF record for your new provider's.
    4. Add your new provider's DKIM record, and keep your DMARC record.
    5. Check the result with a free DNS checker before you rely on it.

    Not sure what these mean? See my email glossary.

  6. 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.
  7. 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.

Gmail to another provider · Outlook.com to another provider · iCloud Mail to another provider · Proton Mail to another provider · Fastmail to another provider · Tuta to another provider · All switching guides

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