Box 3 Calculator: compare 2026 with the WWR proposal
Enter your wealth and instantly see the difference between the current fictitious-return system and the Wet Werkelijk Rendement. Free, no registration.
This free Box 3 calculator compares your Box 3 tax under the current flat-rate system (2026, in force) with a calculation in the style of the Wet Werkelijk Rendement bill (target 2028, not politically certain). The current system uses provisional fictitious rates: 1.28% on savings and 6.00% on other assets. The proposal calculation taxes the return you enter, including unrealised capital gains on investments.
Enter your wealth per category, set your expected return, and see the difference. Wealth allowance in the calculation: €59,357 (2026, in force). Tax-free result: €1,000 per person, €2,000 with a fiscal partner (2× assumption). That is the 2028 cabinet-letter proposal, not law yet. The earlier WWR bill named €1,800. This tool does not use that figure.
How do I read the Box 3 calculation?
The calculator shows your tax under the 2026 system and under the proposal calculation, plus the net difference. A positive difference means more tax under the proposal. At a return below about 6.00% (2026 other-assets rate, in force), the proposal can come out lower than the current flat rate.
More Box 3 calculators and context
Indicative calculation based on published legislation. Not tax advice. Consult a tax adviser for your personal situation.