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Written By
Simran Bhatia -
Approved By
Sonika Rawat -
Updated on
May 18th, 2026 -
Read Time
7 minutes
“A R&D company is switching from Tutanota to Microsoft 365 (E5) due to Microsoft’s advanced compliance features. Since Tutanota does not support IMAP, the IT team tried manually exporting EML files for 150 users. This caused major issues with version control and resulted in the loss of metadata for all 150 users. What is the ideal way to migrate all of those emails from Tutanota to Microsoft 365 at scale without losing original timestamps and folder structures?”
Organizations that prioritize privacy as their topmost concern often find Tutanota (now Tuta) as their initial communication client. But the needs of growing enterprises demand a more secure, cloud-based, and service-integrated platform like Microsoft 365. But it’s quite challenging due to Tutanota’s End-to-End encryption (E2EE) security. It doesn’t work with IMAP and POP3 directly, so let’s find out how you can conveniently migrate Tutanota to Microsoft 365, either free or with the SysInfo EML to Office 365 Migration Tool, without affecting data integrity.
Tutanota is a German-based email application with high-end security that often locks users’ data with no access scope. Also, even if it is highly secure, it cannot compete with the modern-day Microsoft 365 platform offering robust security, regular updates, collaboration and productivity features, and simplified data sharing suitable for compliance. Furthermore, the key pointers to note are:
Even though you can save Tutanota files on the PC and proceed with their transfer into M365 using manual and professional solutions. Here are some common problems that can arise in between:
We all know that Tutonate emails need to be first extracted for further transfer into Microsoft 365. Now, this is possible by using the Tuta application itself. Once you have the emails, you can use Outlook for import into M365 free or with the specialized software tool for secure migration. Understand the step-by-step process in detail here.
Before proceeding, ensure you have an active Outlook connected with Office 365, the Tutanota desktop application installed, free Office 365 storage, and admin access to the accounts. Steps to follow further are:
Note: Maintain a safe backup of the Tuta EML files until they are verified, accessible, and viewable in Office 365. Once the verification is complete, then only delete your Tuta account (if required).
Shortfalls:
SysInfo EML to Office 365 Migration Tool is a top-notch solution to instantly transfer emails, contacts, and calendars in bulk without difficulties. It allows you to securely connect to the Microsoft account via OAuth and ensures no data loss happens during the migration. You can even customize the data before migrating as required, i.e., remove duplicates, apply date filters, handle attachments, and more. The migration tool is easy to use and works on all versions of Mac and Windows. Using it, you can even import EML to Reddifmail and other clients reliably and flexibly.





Why Large Enterprises Trust Migration Tools?
Case Study:
A startup needed to migrate emails from Tutanota to Microsoft 365 for 55+ users to satisfy the compliance requirements as needed by their new partners. However, the challenge lies when they migrated emails manually, and it started lagging after a few files with metadata, and the Sent Items date was lost. This resulted in the trial’s invalidation. Next, they opted for the SysInfo EML to Microsoft 365 Migration Tool and rebuilt the structure completely, transferred files accurately, and saved them all with 100% integrity and zero loss. Migration completed within a few hours without downtime, and the next trial went by smoothly, offering great results.
Migrating from a privacy silo environment like Tutanota to a collaborative workspace like Office 365 needs a systematic approach. The lack of IMAP support makes it difficult to move emails between accounts such as Gmail, Yahoo, or others. This is why in this guide, we discussed effective solutions to migrate Tutanota to Microsoft 365 free and with the ideal SysInfo EML to Office 365 Migrator. With the former, you may have to face some limitations, whereas the latter ensures secure transfers without risks and hassle.
Ans. Yes, you can transfer emails from Tutanota to Microsoft 365 with or without attachments using the SysInfo EML to M365 Migrator. It handles even the large and bulky documents, image files, and other attachments with full ease.
Ans. The migration time depends on the volume of the Tutanota mailbox and the method opted for. For a few files with manual migration, it may take a few hours to a day. With the EML to Office 365 Converter, even the large mailboxes of 15 GB can be migrated in minimal time.
Ans. Yes, technical knowledge is needed when you are migrating Tutanota to Microsoft 365 manually. If you are using the professional EML to Office 365 Exporter, then no technical knowledge is needed, as it is user-friendly and self-explanatory.
Ans. Yes, migrating contacts and calendars from Tutanota to Microsoft 365 is done automatically with the EML to O365 Migration Tool. It fetches all the mailbox items. However, if you are using the manual method, then you need to first extract contacts as CSV/vCard and Calendars as ICS, convert them to PST, and then import them into Microsoft 365.
Ans. Small and large organizations ensure safe migration between Tutanota and Microsoft 365 by performing migrations offline, running a pilot test, using a secure authentication channel, and a tool like SysInfo EML to Office 365 Migration Software that supports batch conversions.
About The Author:
Simran Bhatia is a technical content writer engaged in writing clear, concise, and SEO-optimized content. With a background in computer science and a passion for writing, I thrive to deliver complex technical content in simple layman terms.
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