When will Hamburg move away from Microsoft?

Since the beginning of 2025, a lot has started to change in Europe when it comes to digital sovereignty. I would like to focus on one particular issue: the dependency of public administrations on Microsoft.

When US President Trump imposed sanctions on the chief prosecutor of the International Criminal Court, Microsoft blocked his email account. This raised serious questions across Europe about how much public administrations depend on American technology companies. It showed that decisions made by the US government can affect the access of people and organisations in Europe to important digital systems. In the worst case, a person or organisation could suddenly lose access to a large part of its digital infrastructure.

How dependent is Hamburg on Microsoft?

Hamburg already depends heavily on Microsoft. After searching through the Hamburg Parliament database, I found that the state started its productive migration to Microsoft 365 in 2023. Microsoft 365 includes many Microsoft products, including the Office suite, but connects them through a cloud-based platform. With this migration, Hamburg’s districts, major ministries, state enterprises and many other administrative bodies became connected to the Microsoft 365 environment.

The migration project itself cost Hamburg around €8 million. The state also pays Dataport, a publicly owned IT service provider that operates and maintains many of Hamburg’s IT systems. These costs were around €823.000 in 2024, €1.250.000 in 2025 and are expected to reach €1.475.000 in 2026.

After seeing these numbers, I wanted to know how much Hamburg pays Microsoft directly for licences. I had already read that the German federal government pays around €500 million per year for Microsoft products. Unfortunately, I could not find a similar number for Hamburg. The state does not publish its Microsoft licence costs because it considers the prices confidential under public procurement rules. This means that we know some of the migration and operating costs, but we still do not know the complete bill.

Hamburg is also planning to expand its use of Microsoft Teams, which is part of Microsoft 365. As far as I understand, the state still relies on Skype, and I also found costs for Cisco Webex and Zoom in some documents. Moving more communication into Microsoft Teams means that instead of reducing its dependency on Microsoft, Hamburg may become even more dependent on the company.

This dependency also has a direct cost for taxpayers. Microsoft is increasing prices while investing heavily in AI infrastructure, and public administrations have little room to refuse these increases when their systems already depend on Microsoft products. In the end, taxpayers have to cover the higher costs.

Other German states are moving in the right direction

One clear example is Schleswig-Holstein. In October 2025, the state announced that it had migrated around 30.000 employees away from Microsoft products such as Office, Outlook, Exchange, SharePoint and Active Directory. These products are being replaced with open-source alternatives such as LibreOffice and Nextcloud.

The migration is not yet fully complete, but Schleswig-Holstein expects to save more than €16 million in licence costs. It has also allocated €8 million for the migration and the further development of open-source software.

More recently, Mecklenburg-Western Pomerania announced that it had migrated 5.000 employees from Microsoft SharePoint to Nextcloud. The state plans to increase this number to 50.000 and is working together with Schleswig-Holstein during the process.

Does Hamburg have a plan?

After reading about these two states, I wanted to know whether Hamburg had a similar plan. Unfortunately, I could not find an approved migration plan or a date for moving away from Microsoft.

The first concrete development came in April 2026, when Hamburg proposed a structured examination of openDesk, an open-source office and collaboration environment developed under the federal Centre for Digital Sovereignty, ZenDiS. Hamburg will review Schleswig-Holstein’s experience, compare the costs of Microsoft and openDesk over at least five years, identify missing functions and training needs, and run a limited test inside the administration. The Senate is expected to report to the Hamburg Parliament by 1 December 2026.

This is not yet a decision to move away from Microsoft. It is only a test to understand whether openDesk could work in Hamburg, how much a migration would cost and which parts of the administration could use it. By the end of 2026, we should know more about whether Hamburg is seriously preparing a path away from Microsoft or only studying the possibility.

For now, Hamburg has no plan or date to leave Microsoft. The openDesk report expected in December 2026 may show whether that is about to change.