Update: November 2025
The taxation of assets in Box 3 of the Dutch income tax system remains a recurring topic. Since the Dutch Supreme Court’s so-called ‘Christmas ruling’ (Kerstarrest) in 2021, the tax system has undergone several adjustments, yet many uncertainties remain in 2025. This article provides an overview of the most important developments and practical aspects relevant to high net worth individuals, entrepreneurs and real estate investors.
From flat-rate (assumed) return to actual return
In the Christmas ruling, the Supreme Court decided that the flat-rate return system violated the European Convention on Human Rights up to and including 2020. Taxpayers who had lodged appeals for the years 2017–2020 were automatically entitled to have their rights restored.
The Box 3 Legal Redress Act subsequently introduced a distinction between savings and other assets, but it was still largely based on flat-rate returns. In 2023, the Dutch Attorney General recommended that this restoration of rights was still insufficient. He advocated a system of taxation based on actual returns.
Supreme Court ruling and introduction of a rebuttal scheme
On 6 June 2024, the Supreme Court confirmed that taxpayers are entitled to have their legal position restored if their actual return is lower than the flat-rate return. This applies retroactively to all years from 2017 onwards. In response, the Box 3 Rebuttal Scheme Act was passed on 8 July 2025. This Act enables taxpayers to prove their actual returns for the years 2017 to 2024 by completing the ‘Opgaaf Werkelijk Rendement’ (Declaration of Actual Return) form.
The Dutch tax authorities started sending out these forms in the summer of 2025. Taxpayers can use them to demonstrate that their actual return was lower than the flat-rate return. In this case, the tax assessment will be adjusted. Final tax assessments are now being used for the years from 2021 onwards, with the OWR form serving as a correction mechanism.
Value developments of real estate and other assets
The tax authority includes the following components in the actual return:
For real estate:
- Both realised value developments (rental income excluding gas, water and electricity costs) and unrealised value developments are taken into account.
- The calculation is based on the WOZ value (property valuation):
- Initial value: the WOZ value as at 1 January of the tax year.
- Final value: the WOZ value as at 1 January of the following year.
- In the case of purchases/sales during the year, the calculation is made on a pro rata basis.
- If no WOZ value is available, the market value applies.
- Investments that lead to an increase in the WOZ value can be excluded if justified.
- Own use (e.g. second home) is set to zero for the years up to and including 2025 (from 2026 onwards, a benefit from own use should be taken into account).
For other assets (such as shares, bonds and investment funds):
- Both realised and unrealised performance is taken into account.
- Capital gains and losses are taken into account even if no sale has taken place.
- Income such as dividends and interest is taken into account in full.
- Costs (such as management costsor transaction costs) are generally not deductible.
Additionally, loss compensation between years is not permitted within Box 3.
Please note that by taking unrealised capital gains into account, this method may result in a higher taxable income than was actually achieved. NeD Tax assesses each case individually to determine whether it makes sense to appeal against the tax assessment.
Box 3 in 2024 and 2025
The tax rate for 2024 has been set at 36%. The flat-rate return percentages are:
- Bank balances: 1.03%.
- Investments and other assets: 6.04%.
- Debts: 2.47%.
The tax rate will also remain at 36% in 2025. The return percentages for this year will be set in early 2026. It is expected that the flat-rate return will again exceed the actual return, meaning that many taxpayers will be entitled to a refund.
Taxpayers have now been sent a written request by the tax authorities to complete the OWR form. This form must be submitted for each tax year. If the actual return exceeds the flat-rate return, the tax will not be increased.
Outlook for 2026 and beyond
For 2026, the flat-rate return for other assets has been set at 6%. The previously planned increase in the flat-rate return for investments will not be implemented. At the same time, the tax-free allowance will increase to €59,357 per person (or €118,714 for fiscal partners).
The introduction of the new Box 3 system based on the actual return has been postponed until 1 January 2028. Until then, the current system of flat-rate returns and a rebuttal scheme will remain in force.
Practical points to note
- Check whether you have received a letter from the tax authorities regarding the Opgaaf Werkelijk Rendement (declaration of actual return).
- Compile data on your actual return, such as WOZ values, rental income and investments, at an early stage.
- Ask your tax advisor to complete the OWR form as soon as you receive it.
- Appeal against final tax assessments that include an increase in value.
- Take into account the higher tax burden in 2026 and plan your assets and investments accordingly. We can support you in this with our tax advice and financial planning services.
The following considerations are relevant for property investors:
- Review your strategy: do you hold property privately or through a legal structure (e.g. a B.V.)?
- Consider transferring new investments into a legal structure.
- Consider selling existing properties. Please note that transferring properties to a Dutch private limited B.V. may result in transfer tax being levied (2025: 10.4%, and from 2026, 8% for investment properties or 10.4% for other properties that are not your own residence).
NeD Tax supports high net worth individuals, entrepreneurs and investors with tax issues relating to Box 3. Please contact us for a personal consultation.
