Finance
Refinancing & Remaining Debt Calculator (Anschlussfinanzierung)
Calculate the remaining debt at the end of your fixed-interest period and the new monthly payment of your follow-up financing at a changed interest rate.
- Last updated:
- Editorially reviewed
Inputs
Results
- New monthly payment
- €918
- Remaining debt at end of fixed period
- €183.689
- Amount repaid by then
- €56.311
- Current monthly payment
- €1.100
- Difference per month
- -€182
Run the numbers on a real property
With the address, size and price: financing, tax, cash flow and nearby comparable rents in one analysis.
If a property loan is not fully repaid when the fixed-interest period (Zinsbindung) ends, a remaining debt (Restschuld) is left that needs to be refinanced. If interest rates are higher then than at signing, the monthly payment can rise significantly. Our calculator determines the remaining debt at the end of the fixed period and shows the payment you can expect for the follow-up financing.
How to use this calculator
The calculator simulates the amortization of your annuity loan over the fixed-interest period:
- Step 1: Enter the original loan amount.
- Step 2: Enter the current interest rate and the initial repayment rate. Together they make up your annuity.
- Step 3: Choose the length of the fixed-interest period (for example 10 or 15 years).
- Step 4: Enter the expected follow-up interest rate. The calculator assumes the repayment rate is kept unchanged.
Understanding the results
The calculation shows where you stand at the end of the fixed period:
- Remaining debt: the part of the loan not yet repaid, which needs follow-up financing.
- Amount repaid: how much of the loan you have already paid off during the fixed period. The repayment share grows year by year.
- Current and new monthly payment: today's payment compared with the payment after refinancing at the new rate.
- Difference per month: the additional or reduced monthly burden, the decisive number for your cash flow planning.
Why refinancing belongs in the investment calculation
Anyone calculating only with today's payment easily underestimates the interest rate risk: with 10 years fixed interest, 2% initial repayment and a rate between 2 and 4%, about 76 to 78% of the loan is still outstanding at the end of the fixed period. If rates rise by two percentage points during that time, the new payment can flip a rental property's cash flow from positive to negative. Investors should therefore plan the follow-up financing from day one: calculate with conservative rate assumptions, choose a sufficiently high repayment rate and use extra repayment rights (Sondertilgung) to push down the remaining debt. Acting early also lets you lock in the follow-up rate a few years in advance with a forward loan.
Frequently Asked Questions
What is the Restschuld (remaining debt)?
The remaining debt is the part of the loan not yet repaid at the end of the fixed-interest period. It must either be refinanced (with the same or a new bank) or repaid from your own funds.
How high is the remaining debt after 10 years typically?
With 2% initial repayment and around 3.5% interest, roughly 23 to 24% of the loan is repaid after 10 years, and more than 75% remains outstanding. A higher repayment rate or extra repayments reduce the remaining debt considerably.
What happens if rates are higher at refinancing time?
The monthly payment rises because the remaining debt is served at the new, higher rate. Each additional percentage point raises the monthly payment by 1% of the remaining debt divided by 12: with a remaining debt of €200,000 that is about €167 per month, and about €333 for two percentage points.
When should I start arranging the follow-up financing?
Well before the fixed-interest period expires, so there is enough time to compare offers. With a forward loan you can also lock in the current rate level for a fixed period that ends only in a few years.
These calculations are for informational purposes only. Consult a professional for financial advice.