ZDNET’s key takeaways
- The Netherlands stopped a government agency’s shift to Microsoft 365.
- The drive toward an open-source, digital sovereignty approach continues.
- What the Netherlands will move to next is quite vague.
The Netherlands’ Tax and Customs Administration has abandoned its planned Microsoft 365 public-cloud rollout.
Why? The reasons were clear at the Open Source Summit Europe conference, where the Linux Foundation (LF) released the 2026 State of Open Source in Europe. In it, the nonprofit, pro-open-source organization revealed that 94% of European Union (EU) organizations say digital sovereignty is important, with 61% considering it very important. As Thierry Carrez, the Linux Foundation Europe GM, said in his keynote, “Europe has clearly heard the message on digital sovereignty.”
The Netherlands isn’t alone
It’s not just the Dutch tax collectors, though. The Netherlands is also exploring switching from Windows and proprietary software to Linux and open-source programs across the board. That follows the Swiss military and other agencies announcing they were moving to Linux and openDesk, a German open-source office suite. Before that, European governments shifting to Linux included Austria, France, Germany, and Ireland.
Indeed, according to the LF Europe report, 94% of organizations care about AI as much as they do about digital sovereignty. We all know how businesses are moving to AI as fast as they can. Outside the States, the move to digital sovereignty is garnering just as much support.
The Netherlands had planned to switch to Microsoft 365 in 2025. The idea then was to complete the rollout by the end of 2026. About 5,000 employees had already migrated when the Dutch Advisory Council on ICT Assessment recommended reversing the public-cloud rollout in June. The government paused the plan in July; the latest announcement replaces that rollout with an on-premises/open-source approach.
The Tax and Customs Administration isn’t replacing all of Microsoft Office with a single open-source suite, at least not yet. Instead, the government will keep the existing Microsoft software for now.
Looking ahead, State Secretary for Finance Eelco Eerenberg set out the replacement timetable in a letter to Parliament: “In 2027, the provision for mail and calendar will be realized on-premises. Later in 2027 and 2028, European open-source solutions for personal storage and collaboration will follow. This allows us to work toward a sustainable and more autonomous solution for these functionalities.”
Why the Netherlands pulled back
The ICT assessment found that the chosen Microsoft 365 public-cloud design fell short on “information security, information processing and future-proofing.” Another key concern was preserving data confidentiality and control. In particular, the ICT assessment raised concerns about sending confidential documents through American servers rather than the government networks previously used.
The Dutch government is also concerned about 365’s encryption. The proposed 365 setup relied on standard Microsoft encryption rather than Double Key Encryption. The latter would have given the administration greater control.
Another worry was that end-to-end encryption wouldn’t have been enabled by default for one-to-one Teams calls. This has long concerned the Netherlands government. On top of that, it would have been unavailable for group calls under the selected configuration. These were criticisms of the deployment design, not claims that every Microsoft 365 configuration has identical disadvantages.
Also: Got a Microsoft 365 subscription? Your storage is about to shrink
Finally, the assessment identified vendor lock-in, reduced flexibility, concerns about digital sovereignty, and the absence of an adequate exit strategy as showstopping issues. In my view, based on my coverage of the European Union’s push for digital sovereignty, they don’t trust American companies under the current US government.
What’s next
For now, the on-premises email/calendar environment will still use Microsoft software, including Outlook. The open-source portion concerns personal storage and collaboration, not a wholesale replacement of Word, Excel, PowerPoint, or the entire desktop environment.
What exactly will this look like? We don’t know yet. No particular open-source programs or software stacks have been chosen yet. What we do know, though, is that other Dutch government agencies have started developing Digitaal Autonome Werkomgeving Overheid (DAWO), which translates to “Digital Autonomous Work Environment for Government.” DAWO starts by replacing the Windows desktop with the Dutch Linux distribution NixOS.
Also: 98% of IT leaders want digital sovereignty: Now SUSE is operationalizing it for companies everywhere
On top of NixOS, France’s La Suite and Germany’s openDesk are being considered for the desktop suite. Another possibility is that the Netherlands will move to a homebrew of MijnBureau. This self-hosted suite combines open-source projects, including Nextcloud for storage and collaboration, Collabora for office documents, Element for messaging, and OpenProject for work management. This is a more ready-to-run office suite than what I’d call a Netherlands agency’s built-from-scratch “Dutch Office” suite.
Still, while the replacement details remain foggy, Dutch tax authorities have canceled the Microsoft 365 cloud rollout in favor of an on-premises email/groupware suite, followed by a full-fledged open-source office suite.