📊 Unrealized Gains Tax Simulator

Simulating the impact of the proposed Dutch Box 3 reform on long-term wealth accumulation

💰 Portfolio Settings

Starting Capital (€)

Simulation Duration (years)

Monthly Savings / Withdrawal (€)

Positive = savings, Negative = withdrawal

Unrealized Gains Tax Rate (%)

NL Box 3: 36%. Set 0 for no-tax baseline.

Allow loss carry-forward

Tax-free allowance (€)

2025 Box 3: €57,000 pp. Set 0 to ignore.

Show DE capital gains tax comparison

Index / Return Model

Number of Simulations

More paths = better statistics, slower render

Show no-tax comparison (0% rate)

Y-Axis Scale

Smart clips extreme paths for readability

Configure parameters and click ▶ Run Simulation to begin.