What happened?
Hungary’s National Tax and Customs Administration announced the availability of Form 25GLBADO in the ONYA online system on 21 October 2026. It supports reporting for global minimum top-up taxes and the qualified domestic minimum top-up tax advance.
Key details
The form is filed electronically through ONYA. Groups should use NAV’s completion instructions, identify the responsible Hungarian entity or designated local entity, and arrange the necessary representation authority before submission.
Effective date / timing
For a 2025 reporting period ending on 31 December 2025, the domestic top-up tax advance return and payment are due on 20 November 2026. Final returns normally follow a 15-month timetable. Where 2025 is the transition year, the 18-month filing period gives 30 June 2027. Non-calendar periods require their own calculation; payment obligations should be checked separately.
Business impact
Tax & Markets analysis: the immediate task is to reconcile the advance calculation with group Pillar Two data and cash-flow plans. Maintain separate owners and sign-offs for the November advance and the later final return; releasing the form does not merge these obligations or reset their deadlines.
Sources
Primary and secondary sources are distinguished below. See our methodology for verification and correction standards.