Hub for Box 3 wealth taxation: provisional method overview, calculator guide, glossary links, and coverage gaps.

Box 3 hub

Quick answer: Box 3 taxes a notional return on savings and investments above an exemption under rules that can change by tax year. Use the Box 3 guide for a provisional 2026 planning estimate.

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Coverage gaps

Verify volatile figures on Belastingdienst pages and our methodology.