How to Import PST to Office 365 (Microsoft 365): 3 Methods

Situation	Method	Outlook Required?	Microsoft 365 Admin Access?	Best suited for
One PST and one mailbox	Classic Outlook Import/Export	Yes	No special import role	Individual mailbox migration
Multiple PST files or mailboxes	Microsoft Purview PST Import Service	No	Yes	Organizational/bulk migration
No Classic Outlook or need an alternative workflow	PST migration tool	No	Depends on the software and account configuration	Simplified or selective migration

Microsoft’s PST Import Service is designed for admins who want to bulk import PST files into mailboxes in Exchange Online. Before the PST data is mapped to target mailboxes, the network-upload workflow uses Microsoft-provided Azure Storage and AzCopy.

If you have Classic Outlook and just need to move one PST into your own Microsoft 365 mailbox, the Outlook Import/Export wizard is usually the most direct route.

Method 1: Import PST to Office 365 Using Classic Outlook

Classic Outlook for Windows can import email, contacts, calendar items and other supported PST data directly into a Microsoft 365 mailbox.

When is this method suitable?

• You have the classic version of Outlook installed.
• You have to import one or several PST files.
• Sign in to the destination Microsoft 365 account in Outlook.
• No need for the administrative bulk-import workflow.

The current directions from Microsoft are File > Open & Export > Import/Export, and you can select the Microsoft 365 mailbox as the destination.

Follow the below given steps to open PST file in Office 365 using Outlook email client:

1. Click on File and choose Add Account.
   
2. Enter your Office 365 webmail account and click Connect.
   
3. Type in the password for your Microsoft 365 account and click Sign In.
   
4. Follow the instructions to set up your account and click OK when you’re done.
   
5. Again, open Outlook on your computer and go to File.
   
6. Click Import/Export to open the Import and Export Wizard.
   
7. Choose Import from another program or file and click Next.
   
8. Select Outlook Data File (.pst) and click Next.
   
9. Click Browse to find the PST file select options; click Open.
   
10. Choose the folders of PST files and click Finish.
    

Finished!! You just need to follow these simple steps to import Outlook data file to Office 365 webmail account directly.

Important: New Outlook and Classic Outlook

Don’t confuse opening a PST with importing a PST into a Microsoft 365 mailbox.

Classic Outlook workflow = Traditional PST Import/Export wizard. If you are using New Outlook and do not see File > Open & Export > Import/Export, use Classic Outlook for this migration workflow. The current Microsoft guidance and current Microsoft Q&A discussions (October 2023 and 2026) still separate the Classic Outlook PST import workflow from the New Outlook PST limitations.

What if I just need a couple of PSTs?

You don’t necessarily have to import the full file.

In Classic Outlook you can use:

File >> Open & Export >> Open Outlook Data File

to open the PST and then copy or drag and drop selected messages or contacts into Microsoft 365 mailbox folders.

Method 2: Upload PST to Microsoft 365 Using Purview PST Import Service

This method is offered by Microsoft itself to help administrators open PST file in Office 365 account. However, the whole method is lengthy and complex, which is why we have divided it into 4 major steps to ease the whole process.

Before proceeding with this method, you have to be assigned the Mailbox Import Export role in Exchange Online to create import jobs. Without it, you can not see the Import option in Purview at all.

Step 1. Assign Mailbox Import Export Role

1. Go to Exchange Admin Center > Roles > Admin Roles.
   
2. Choose Organization Management.
3. Open the Permissions tab and check Mailbox Import Export.
   
4. Click Save.

Note: It takes 24 hours for the change to apply(usually works within an hour).

Step 2. Create a SAS URL

The SAS URL is used to temporarily store PST files in Azure Blob Storage before importing them into Office 365.

1. Sign in to Microsoft Purview Compliance portal.
2. Go to Data Lifecycle Management and choose Microsoft 365.
   
3. Choose “Import” in the Data Lifecycle Management Overview section and click on +New Import Job.
4. Give the job a name and click Next.
   
5. Select Upload your data > Next.
   
6. Click on Show network upload SAS URL to generate the SAS URL.
   
7. Copy the SAS URL to use in later procedures.
   

Step 3. Upload PST Files to Azure with the AzCopy Utility

Upload PST files to Azure Blob Storage using the Azure AzCopy command-line tool.

1. Download AzCopy and place it in the C:\Temp folder. AzCopy V10 is just an executable file, nothing to install.
2. Open Command Prompts administrator and change to the folder containing azcopy.exe.
3. Now, Run:
   azcopy.exe copy “C:\Temp\PSTs” “<your-SAS-URL-here>” –recursive=true
4. Now visit the location of your PST file. Right-click on PST file and click on Properties to copy the PST file path and update.
   
5. Replace the local path with your actual PST folder and paste your full SAS URL.
   C:\>cd C:\Temp\
   C:\Temp>azcopy.exe copy “C:\Temp\PSTs” “https://e5c2666294514f92b02da36.blob.core.windows.net/ingestiondata –recursive
6. Run the command to copy the PST file to Azure. The output will show like this.
   
7. Now back to Exchange Preview.
8. Enable check box: I’m done uploading files and I have access to the mapping file.
   
9. Now, click on Next button.

Step 4. Upload CSV Mapping File

1. Download the sample CSV template from Microsoft: https://go.microosft.com/fwlink/p/?Linkld=54417
2. Open the downloaded file and edit it according to your requirements.
3. Save the file after making the changes.
4. Go back to the import wizard and click Upload file.
   
5. Browse and select the updated CSV file.
6. Run the validation to make sure there are no errors.
   
7. Once validation is successful click Next to Continue.
   

Step 5. Final Verification & Submission

1. Now verify all details and press the Submit button.
   
2. The file will be uploaded to cloud.
3. After uploading, click Done button.
   

Step 6. Start PST Import to Office 365

1. Choose the checkbox in front of the Import Job.
   
2. Click on Import to Office 365 button.
3. Select No, I want to import everything and click Next.
   
4. After that, click on Submit.
   
5. Upload to the cloud succeeded. Click Done.
   

Step 7. Verify PST Import Job Completion Status

1. Click on the Import Job to verify the PST import job status. After that, verify that the PST import job shows the status completed.

Office 365 import PST process complete!

What About PowerShell PST Import?

Older tutorials recommend using New-MailboxImportRequest to import PST files to Microsoft 365.

That is the Exchange Online data.

Microsoft now says that New-MailboxImportRequest is no longer supported in Exchange Online and directs administrators to the network-upload PST Import Service instead. The cmdlet still applies for supported on-premises Exchange scenarios.

So, don’t use New-MailboxImportRequest as the primary way to import PST files to an Exchange Online/Microsoft 365 mailbox.

Method 3: An Alternative Way to Import PST to Office 365 Without Outlook

If you want to avoid the manual Outlook import process or the administrative steps involved in Microsoft’s bulk-import workflow, a dedicated PST migration tool may be worth considering. Users researching PST migration on Reddit may also find discussions comparing manual methods and third-party solutions.

Advik PST Converter is one option designed to import PST files directly into Office 365 without requiring Outlook. It supports batch PST migration and helps retain the source folder hierarchy and email attributes during the transfer.

This method may suit users who need to import multiple PST files or prefer a guided migration process. Before proceeding, check the tool’s current features, account requirements, and trial limitations to ensure it meets your needs.

 

Note: The freeware or trial edition will migrate 25 emails for free.

Steps to Import PST to Office 365 Using Advik PST Converter

1. Run PST to Office 365 Import Tool and click Select Files to add PST file.

2. Select mailbox folders that you need to import and then press Next.

3. Choose Office 365 from the given list of Select Saving Option.

4. After that, enter your Office 365 account login details in respective field.

5. Finally, click the Next button to start the import process.

Done!! The software will start transferring emails from PST into Office 365 automatically. Once done, open your Office 365 Webmail account and find your emails in the AdvikSoft Label folder.

Watch How Office 365 Import PST Files

Check That the PST Import Was Successful

Just because the migration job says the import is complete, don’t assume it is.

After you import your PST data to Microsoft 365, verify the mailbox where the data was imported.

• Verifying Checklist
• Open the Microsoft 365 mailbox.
• Look in the Inbox for the expected messages.
• Check Sent folder.
• Check custom folders/subfolders.
• Open multiple messages and attachments.
• Check important items on the calendar.
• Check for contacts if they were in the PST.
• Count the representative items in the PST and compare to the destination mailbox.
• Check to see if anything was missed or marked as damaged.
• Make sure the most important folders and messages are there.

According to Microsoft, the PST Import Service process can ignore PST items that are damaged, and the import status will include information about items that have been ignored.

If it’s a major migration, keep the original PST until your verification is complete.

Common PST Import Problems and Fixes