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Why Move Outlook Emails to Microsoft 365?
Running Outlook locally made sense for years. Then storage limits started creeping up, security patches became a weekly chore, and IT realised managing individual mailboxes one by one just doesn’t scale.
Microsoft 365 solves a chunk of that at once. Your mailbox lives in the cloud. Storage stops being a constant negotiation. Microsoft handles security updates instead of you.
A few reasons companies actually make the jump:
- Scaling storage without buying more hardware.
- Security and compliance controls running from one place.
- Access to Teams, SharePoint, and everything else in the Microsoft
- ecosystem.
- Less server maintenance for IT to deal with.
- Easier remote access if your team’s spread out.
No matter what’s driving it, you want the same thing in the end. Get the mailbox into Exchange Online, keep everything the way it was, and quit relying on local PST files that break the second a hard drive dies.
Best Methods to Migrate Outlook Inbox to Exchange Online
There are really two ways to handle this. One’s professional and built for speed. The other’s manual, using tools Outlook already gives you.
Both paths get you there in the end. What changes is how much manual work you’re up for, and honestly, how big that mailbox is to begin with.
Migrate Outlook Emails to Office 365 Using Professional Solution
Most people land here once they have more than a couple of mailboxes to manage, or one mailbox that’s too big to handle by hand.
BreviSoft Import PST to Office 365 Tool plugs straight into your PST file and moves everything into Microsoft 365 for you. No exporting anything yourself. No rebuilding folders one by one. No sitting there staring at a progress bar, hoping it didn’t just stall.
Follow the Steps to Migrate Outlook Email to Office 365 Using BreviSoft:
- Install the BreviSoft Import PST to Office 365 Tool on your system.
- Select the PST file that you want to migrate.
- Let the tool scan and display the mailbox contents, folders, emails, contacts, and calendar items.
- Enter your Microsoft 365 admin or user credentials.
- Choose which folders to import, or select everything for a full migration.
- Click the Import button and let it run.
- Check your Microsoft 365 mailbox once it’s finished to confirm everything landed correctly.
What makes this approach worth the extra step:
- Keeps folder structure exactly as it was in the original PST.
- Handles large PST files without freezing or timing out.
- Supports bulk imports for multiple mailboxes at once.
- No data loss, no duplicate emails cluttering the new mailbox.
- Minimal technical know-how required to run it.
For an IT admin migrating several employee mailboxes during a company-wide switch, this method usually saves real time. Less clicking around, less troubleshooting, more actually getting the job done.
Transfer Outlook Mailbox to Exchange Online Using Manual Solution
If you’ve only got one or two mailboxes to move, and don’t mind spending a bit of time on it, Outlook’s own export and import tools can get you there for free.
Steps to Migrate your Outlook emails to Exchange Online Using Outlook Import/Export:
- Open Outlook and go to File, then Open & Export, then Import/Export.
- Choose “Export to a file,” then click Next.
- Select “Outlook Data File (.pst)” and click Next.
- Pick the mailbox or folder you want exported, and enable “Include subfolders” for everything.
- Choose where to save the PST file, then click Finish.
- Sign in to your Microsoft 365 account through Outlook, or set it up as a new profile.
- Go back to File, then Open & Export, then Import/Export.
- This time, choose “Import from another program or file,” then “Outlook Data File (.pst)”.
- Select the PST file you just exported.
- Choose the destination folder in your Microsoft 365 mailbox and finish the import.
This works. It’s free, and it uses tools you already have. But it’s also entirely manual, and every step depends on you doing it right the first time.
Limitation of Manual Solution
Here’s where the cracks start showing.
Big PST files take forever to export, and even longer to import; sometimes they stall with zero warning. Folders don’t always line up right between the old mailbox and the new one, so you end up rebuilding folders by hand that should’ve just carried over. Attachments can also get lost or corrupted, especially in older or larger PST files. Moving more than one mailbox? You’re doing this whole thing over again, manually, for every single account.
For one personal mailbox, this is fine. For an admin trying to migrate an entire department’s worth of accounts to Exchange Online, it’s rough.
Conclusion
Either method gets your Outlook mailbox into Microsoft 365 eventually. Manual works fine for a single mailbox, and it won’t cost you anything but time. But once you’re dealing with a large PST file, multiple accounts, or a full company switch, the BreviSoft Import PST to Office 365 Tool skips the manual grind and moves everything faster, including folders and attachments.
Check your mailbox count and size first. That one thing usually tells you which method to pick.
Frequently Asked Questions
Ans – You can use Outlook’s built-in Import/Export Wizard. It lets you export your mailbox to a PST file, then import that PST into Microsoft 365 at no extra cost. It works fine for one mailbox, but it takes much more hands-on effort than using a dedicated BreviSoft Import PST to Office 365 tool.
Ans – If you want something quick and mostly hands-off, BreviSoft Import PST to Office 365 Tool connects to your PST directly and handles the import for you. Got just one small mailbox? Outlook’s own export and import tools do the job fine too.
Ans – Really depends on your mailbox size. A small one might wrap up in under an hour if you’re doing it manually. Bigger mailboxes, or migrations with several accounts involved, can take much longer with manual tools. BreviSoft software usually gets through it faster and with less time and effort.
Ans – Not always, if you’re going the manual route. You might have to rebuild folders by hand once you’re on the Microsoft 365 side. Tools like BreviSoft Import PST to Office 365 Tool are built specifically to keep that folder hierarchy intact during the import, automatically.
Ans – Manual methods let you handle only one mailbox at a time, which gets old fast when you’re dealing with several users. A tool built for bulk operations, like BreviSoft Import PST to Office 365 Tool, is designed for this kind of multi-mailbox job.
