Number format: this calculator uses German notation throughout — a comma is the decimal separator and a dot groups thousands. “1.234,56” means one thousand two hundred thirty-four euros and fifty-six cents. The figures come from German tax law, so they are shown the way German authorities write them.
Initial repayment rate (anfänglicher Tilgungssatz)
The share of the loan repaid in the first year — together with the nominal rate it fixes the instalment.
In plain language
The initial repayment rate says how much of the debt you pay back in the first year. It is the lever you really control: the interest rate comes from the bank, the repayment rate is yours. One percentage point more costs a noticeably higher instalment — but shortens the term by years and saves far more interest in the end than the higher instalment costs.
In detail
The initial repayment rate is not a statutory figure but banking practice: it states what share of the loan is repaid in the first year and, together with the nominal rate, fixes the annuity. The instalment is loan × (nominal rate + repayment rate) ÷ payments per year and then stays constant. Within that instalment the balance shifts: the interest share falls with the outstanding debt and the repayment share grows by the same amount. That is why raising the repayment rate works more than proportionally — it mainly removes the interest-heavy later years. At a low nominal rate a figure of 1 % is a warning sign: the term then easily runs beyond forty years.
Worked example
250.000 € at 3,75 %, monthly: with 2 % initial repayment the instalment is 1.197,92 €, the term 339 instalments, and after a ten-year fixed period 189.447,36 € is still outstanding. With 3 % the instalment rises to 1.406,25 € — 208,33 € more — the term falls to 260 instalments, and the debt after ten years is 159.171,85 €. Some 200 € more per month therefore shortens the term by more than six years.
In brief
Instalment = loan × (nominal rate + repayment rate) ÷ payments per year. Over time the repayment share grows.
Legal basis: banking practice, no statutory definition · as at 2026