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Planning tool

Portfolio Forecast Calculator

Model how contributions, return assumptions, inflation, dividends, and country tax defaults affect a long-term portfolio path.

Run a scenario

Start with a simple contribution plan. Open advanced settings only when you need more control.

Current invested amount in EUR.
Recurring amount added every month.
Time horizon
Nominal return assumption before optional inflation adjustment.
This model compounds monthly and applies dividend tax defaults from the selected country profile. Capital gains realization timing is not modeled here.
Projected value
€134,248
Total contributions
€85,000
Estimated growth
€49,248
Projected value€134,248
Total contributions€85,000
Estimated growth€49,248

Projected portfolio path

5% net annual growth assumption after optional inflation adjustment.
Projected portfolio value over 10 years for the selected country, ending at €134,248.

Tax drag comparison

Estimated annual total tax (wealth-tax drag + dividend tax) in rolling 12-month buckets (Y1..Yn).

Tax impact details (Primary)

Wealth tax drag (effective)0%
Annual wealth tax (est.)€0
Dividend tax15%
Realized gain tax0%
Unrealized gain tax0%
Dividend yield after tax1.7%
Yearly dividend tax drag0.3%
Using Netherlands Box 3 (2026) with fictional return and tax rate assumptions.

Tax model confidence

Primary
Accuracy75%
Last reviewFeb 25, 2026
Estimated uncertainty (annual drag)+/-0.034%
Estimated uncertainty (drag @10Y)+/-0.107%
Estimated uncertainty (wealth tax/yr)+/-€0
Moderate model confidence: core portfolio tax treatment is modeled for this country. Some country-specific edge cases are still simplified. No per-country source reference is attached yet.

How this helps you plan

Use this portfolio forecast calculator to test contribution plans, compare tax-country assumptions, and set realistic long-term expectations before you invest more.

Best for

  • Estimating future portfolio value from monthly investing
  • Comparing countries with different dividend and wealth-tax drag
  • Seeing how inflation and dividend reinvestment change outcomes

Important limitations

  • Market volatility and sequence-of-returns risk are simplified
  • Broker fees, FX costs, and account-level tax exceptions are not fully modeled
  • Results are scenario estimates, not personalized tax or investment advice

Frequently asked questions

Clear answers on assumptions, tax modeling, and how to use the forecast responsibly.

Transparent and simple

Pricing

Basic

A simple setup for investors who want a clean daily view of their portfolio.

EUR 6 / month
1 year historical backfill
CSV import only
Daily price updates
Advanced

Deeper history and connected workflows for investors who want less manual work.

EUR 9 / month
10 year historical backfill
Broker integrations
Everything in Basic
Pro

Full-depth history and live market updates for investors who want maximum visibility.

EUR 15 / month
Everything in Advanced
30 year historical backfill
Real-time data

No spreadsheets. No noise.

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