NL TOOL
Mortgage interest deduction
What is checked?
This checker uses your marginal box 1 rate with the official higher-income restriction. It estimates the tax benefit on mortgage interest.
Estimated tax benefit
€4,507
- Deductible tax benefit
- €4,507
- Effective deduction rate
- 37.56%
- Net interest cost
- €7,493
- Marginal box 1 rate
- 37.56%
Belastingdienst mortgage interest deduction rules · last reviewed 26 July 2026
Estimate the tax benefit of mortgage interest based on income and rate.
Use it to understand your net interest cost.