How to Import or Migrate Outlook PST / ICS Calendar to Office 365 – Learn the Best Way

Written By Kumar Raj
Anuraag Singh
Approved By Anuraag Singh
Published On December 19th, 2023
Reading Time 7 Minutes Reading

Summary: Learn how to import ICS and PST Calendar to Outlook 365 effortlessly. Get to know about the hassle-free ways to migrate your crucial calendar data from Outlook PST and ICS files into Outlook 365. Dive into manual techniques and discover an easier, automated alternative using a reliable tool for a smooth transition. Unleash the power to manage your calendar schedules effortlessly across platforms!”

Microsoft Outlook stands as a top-tier choice for both personal and professional users worldwide. Typically, Outlook securely stores its data in the PST file format, housing essential mailbox elements like calendars, emails, and notes. This setup ensures comprehensive utilization of MS Outlook’s functionalities. The calendar feature, in particular, is favored by many due to its ability to help manage hectic schedules.

Using the Outlook calendar enables users to create events, schedule appointments, coordinate group meetings, and more. Additionally, sharing the calendar as an internet calendar with email recipients is possible, with control over the shared information. However, some users encounter issues necessitating the migration of Outlook calendars to Office 365.

Importing calendars to Outlook 365 becomes imperative due to its accessibility as a web-based email application, allowing users seamless access from anywhere at any time. To address this, we’ve created an effective solution to import ICS calendars to Outlook 365. In the following section, we’ll explore efficient methods to do the same. First, let’s delve into a scenario to better grasp the importing process.

“Need help! I am having an extremely busy schedule so, the calendar is playing a crucial role in my life. So, I swap my email application from Outlook to O365. Thus, I can access my calendar utility any time and anywhere. Moreover, I need to import the Outlook calendar to Outlook 365 without any kind of trouble. Is it possible? If it is, then please facilitate the instruction so, I can perform the conversion task. Thanks.”

In the above user query, the user is looking for a reliable solution to perform this task, let’s discuss the different ways that can be used to import ICS calendar to Office 365.

Manual Method to Import PST Calendar to Outlook 365

To perform the import task, you must first export the Outlook calendar data to the ICS file format. Because ICS is a standard file format for storing and sharing calendars. It is supported by many email services, email clients, and mobile devices. Once you have an ICS file, you can easily import the calendar into Outlook 365. Follow the steps below to complete the import process.

Stage 1: Save Calendar as ICS File Format

Step 1. Select the calendar in the left corner.

Step 2. Select specified calendar events into the “selected calendar folder” in the utility “My Calendars”.

Step 3. Hit on the option “File” at the left on the top.

Step 4. Choose the “Save As” tab.

Step 5. Now, browse to spot, from where you save the iCalendar file.

Step 6. Here, in the filename option, choose any one iCalendar Format or iCalendar Format.

Step 7. Hit on, an alternative to “Save Selected Appointment” in Save Calendar “calendar name” or whole details along with alternatives in “More Options”.

Step 8. Click on the “Save” button.

Also Read: How to Import PST to Thunderbird Email Client?

Stage 2: Import ICS Calendar File to Outlook 365

Now, to complete this task, you need to import the Outlook calendar exported ICS file into Outlook 365.

Step 1. Firstly, spot the calendar you need to insert and save it to your local machine as a .ics file format.

Step 2. Log in to Office 365.

Step 3. Select “Calendar” in the navigation pane at the bottom.

Step 4. Opt “Add Calendar”>>From the file on the toolbar.

Step 5. Choose the “Browse” option and then select a .ics file, and click “Open”.

Step 6. Here, opt for the presented arrow beside “Calendar” alternate and select the calendar you would like the dates and events to be inserted into.

Step 7. Finally, click “Save” to end the procedure.

Also Read: How to Convert PST Contacts to CSV Without Outlook?

Alternate Way to Transfer Calendar from PST or ICS to Outlook 365

The above-discussed method is very tiresome and time-consuming. Thus, we came up with an alternate solution such as the SysTools Office 365 Import Tool. It has a user-friendly and understandable interface so; a novice user can use it without having any expert help. The tool gives the option to import calendars from PST and ICS file format so that calendars can be easily imported into Outlook 365.

Download Tool Purchase

Import ICS file data from File System to Office 365:

Step 1. Download, install, and launch the software. Choose File System as the source and Office 365 as the destination platform for the import.

Note: If you want to import the PST calendar to Outlook 365 then choose Outlook as the source, The rest all the steps are the same as discussed in the coming sections.

enter source and destination

Step 2. Select Calendar from the Workload selection. Click on the Next button.

workload screen

Step 3. Specify the folder path for ICS files in the Source screen.

Validate Source

Step 4. Arrange files in folders named after respective Office 365 email IDs.

provide details

Step 5. Validate permissions by clicking “Validate” in the tool. Click on the Next button.

Step 6. Provide Admin Email and Application ID details on the Destination Screen. Click on the validate button to verify the required permissions.

provide details

Step 6. Now you can see the destination permissions validated. Click on the Next button.

provide details

Step 7. Proceed to add users from the source account using Fetch Users, Import Users, or Download Template options.

fetch users

Step 8. Review and select users for import from the displayed list.

Step 9. Map source and destination IDs manually or via CSV.

Step 10. Validate selected user source accounts.

validate users

Step 11. Once validated, click “OK” and then “Start Import” to migrate Outlook calendar to Office 365.

start Import

Also Read: How to Migrate Outlook Emails to Office 365?

Final Words

In the, above section, we’ve covered effective methods to import both PST and ICS Outlook calendars into Office 365. While some users can attempt the manual methods to perform this operation, however, this approach comes with its respective limitations as discussed above.

Hence, to address this, we’ve introduced an automated solution for seamlessly migrating calendar data from PST to Outlook 365. Users can choose the method that best suits their needs to flawlessly execute the conversion process.

FAQs Regarding Outlook Calendar to Office 365 Migration

1. Can I directly import multiple ICS calendar files into Office 365?

Unfortunately, Office 365 doesn’t have a direct import feature for multiple ICS files. However, you can utilize the above utility to directly migrate Outlook calendar to Office 365 by following the below 5 steps:

  • Step 1. Download, Install & Launch Software on PC.
  • Step 2. Pick Outlook as Source & Office 365 as Destination.
  • Step 3. Enable Calendar from the Workload Selection.
  • Step 4. Set ICS Folder Path & Log in with Office 365 Details.
  • Step 5. Select User Accounts & Click on Start Import.

2. Are there any limitations during the manual import process?

Yes, there could be a few limitations that could exist, such as

  • The size of PST files allowed for import,
  • Specific file formats supported,
  • Permissions required for performing imports,
  • The number of concurrent import jobs allowed per Office 365 tenant.

You should be aware of these limitations while migrating Outlook calendar to Office 365 manually.

3. What happens to the data in the PST file after importing to Office 365?

Once the data from the PST file is imported into Office 365, it becomes part of the user’s mailbox or calendar in the cloud. If we select only the calendars to migrate then the rest data remains unaffected unless explicitly deleted or modified. Moreover, users can access this data through Outlook or other Office 365 applications.