Denmark will implement the OIOUBL 3 Invoice Package for e-invoicing, introducing enhanced compliance, interoperability, and alignment with European standards starting November 15, 2025. Key updates include clearer business and message-level responses, mandatory two-way profiles, and field adjustments to support structured data like environmental metrics. A phased migration plan ensures a smooth transition, with the old OIOUBL 2.1 format phased out by May 15, 2026.
Source: fiscal-requirements.com
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