The Dutch cabinet favors a broader capital-gains model for Box 3. Current Box 3 rules still apply in 2026. A new system is targeted for 1 January 2028, but legislation is not final. The final rules will determine when private wealth becomes taxable.
Why this matters
Box 3 is private, yet a tax bill can affect a dividend, shareholder loan, or capital injection. The 2026 provisional assessment uses fixed returns: 1.28% for bank deposits, 6.00% for investments and other assets, and 2.70% for Box 3 debts. A lower actual return may reduce the final assessment. Future sale-based taxation makes purchase and sale records more important. Tax paid later is still not company cash.
Example
A founder holds private investments for a possible future capital injection. Their value has risen, but nothing has been sold. The household still has a provisional Box 3 payment to plan for. Meanwhile, the BV needs cash for payroll and supplier invoices. The founder keeps separate household and company forecasts. The portfolio value is not shown as available BV cash. A dividend or capital injection follows only after the private tax position and sale proceeds are known.
XTROVERSO tips
- Keep two cash forecasts. Keep private tax, debt, and investments out of the company cash forecast. List dividends, shareholder loans, and capital injections as separate planned transactions.
- Keep the asset file complete. Save purchase confirmations, transaction costs, annual statements, transfers, and sale records. A current account balance is not enough to calculate a taxable gain.
- Use the current rules for 2026. Put the 2026 provisional assessment in the household payment schedule. Treat a later adjustment as uncertain until the final assessment arrives.
- Check who owns each asset. Record whether an asset is private, held by the BV, or part of an income-tax business. Check this before using private money for the company.
- Treat reform as uncertain. Keep the proposed 2028 system out of today’s cash plan. Do not rely on a rule change to pay an invoice, payroll, or investment.
Need a clearer view of private Box 3 exposure in your company cash plan? We can help separate the assumptions from the decisions
The data, sourcing, and analysis behind this article were conducted by Linda Pavan. AI was not used to identify sources, build the factual basis, or produce the analytical judgment contained here. AI was used only as a drafting aid. The final English text was personally reviewed, edited, and approved by Linda Pavan before publication.
References
- Taxence – Kabinet kiest in box 3 grotendeels voor vermogenswinstbelasting
- Rijksoverheid – Status and design of the proposed 2028 Box 3 regime
- Overheid.nl Wetgevingskalender – Legislative stage and 2028 date
- Belastingdienst – Actual return under the current Box 3 system
- Belastingdienst – Calculation of Box 3 income for 2026
- Rijksoverheid – Box 3 information and historical recovery
- Rijksoverheid – Implementation review of the Actual Return Box 3 Act


