Dutch tax office ditches Microsoft 365 cloud for on-premises alternative

The Netherlands Tax and Customs Administration has abandoned its planned Microsoft 365 cloud migration in favor of services hosted on infrastructure it controls, alongside European open source alternatives. Email and calendars will move on-premises in 2027, followed by storage and collaboration services later that year and in 2028. The letter to parliament from Eelco Eerenberg, State Secretary for Finance, follows an earlier decision to pause the Microsoft 365 rollout. The tax authority selected Microsoft 365 in 2025, but the decision attracted criticism. In June, the Dutch Advisory Council on ICT Assessment recommended rolling back the cloud services rollout, which had reached about 5,000 of the 47,500 employees across the tax, customs, and benefits services, rather than completing it as planned by the end of 2026. According to the board, the design of Microsoft 365 in the public cloud "falls short on information security, information processing and future-proofing." …