For 2026, Box 3 calculations can include a second home's rise in value before a sale pays out. Asset categories and legal rights on key dates shape the provisional calculation. Tax may therefore arise before proceeds reach the owner's bank account.
Why this matters
A rise in value will not pay a tax assessment, supplier invoice or household bill. The actual-return calculation covers the full Box 3 position, including income, gains and losses. For 2026, bank deposits use 1.28%. Investments and other assets use 6.00%. The Box 3 rate is 36%. Keep dated records for private property, savings and family rights outside the company ledger.
Example
A founder transfers a second home through a notarial deed and registration on 30 December. Sale proceeds reach the personal bank account on 3 January. The receipt alone does not show the 1 January position. The deed, registration and settlement statement may show property, a claim or money on a notary's third-party account. In 2026, money on a notary's or bailiff's third-party account is a bank deposit.
XTROVERSO tips
- Make a private balance sheet. List property, savings, investments, private loans, claims, debts and property rights held on 1 January. Keep this file separate from the company ledger.
- Keep year-end documents together. Put the contract, notarial deed, settlement statement, registration record and bank receipt in one dated file. The payment date is only one part of the record.
- Track value through the year. Record opening and closing values, purchases, sales, income and debt. Keep valuation support in the file instead of rebuilding it for the tax return.
- Check the correct tax year. The treatment of money on a notarial third-party account changed from 2023. Do not copy the classification from an older return or dispute.
- Record family property rights. Bare ownership and usufruct can fall in Box 3. Record who holds each right, when it began and how its value was calculated.
- Plan cash separately from value. A paper gain is not spendable cash. Include possible Box 3 costs in dividend, owner-withdrawal and household planning.
Need a second check on a property transfer or private Box 3 file? We review the dates, rights, values and cash impact with you
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
- Belastingdienst – Wat is mijn werkelijk rendement?
- Belastingdienst – Bezittingen en schulden in box 3
- Kennisgroepen Belastingdienst – Derdengeldenrekening notaris en box 3
- Belastingdienst – Berekening box 3-inkomen 2026
- Belastingdienst – Rekenvoorbeelden werkelijk rendement
- Rijksoverheid – Tijdlijn werkelijk rendement box 3


