Herramienta
Mortgage Calculator
Calculate your monthly mortgage payment, total interest, and visualise how amortisation evolves year by year.
Enter the property price, down payment, interest rate, and term to calculate your monthly payment and total mortgage cost. Taxes (VAT or transfer tax) are calculated automatically based on property type.
The amortisation table and chart show how the interest versus principal split evolves each year, so you can understand exactly when your payments shift from mostly interest to mostly debt reduction.
Loan details
Configure your mortgage parameters to calculate the monthly payment and total cost.
Assumption: French amortisation with fixed rate.
Results
Your savings60.000 €
Mortgage amount240.000 €
Mortgage interest147.975 €
Total cost with mortgage447.975 €
Year 30
Principal repaid12.691 €
Interest242 €
Outstanding balance0 €
Amortisation table
| Year | Payment | Interest | Principal | Balance |
|---|---|---|---|---|
| 1 | 12.932 € | 8327 € | 4606 € | 235.394 € |
| 2 | 12.932 € | 8163 € | 4770 € | 230.624 € |
| 3 | 12.932 € | 7993 € | 4939 € | 225.685 € |
| 4 | 12.932 € | 7817 € | 5115 € | 220.570 € |
| 5 | 12.932 € | 7636 € | 5297 € | 215.273 € |
| 6 | 12.932 € | 7447 € | 5485 € | 209.788 € |
| 7 | 12.932 € | 7252 € | 5680 € | 204.107 € |
| 8 | 12.932 € | 7050 € | 5883 € | 198.225 € |
| 9 | 12.932 € | 6841 € | 6092 € | 192.133 € |
| 10 | 12.932 € | 6624 € | 6308 € | 185.825 € |
| 11 | 12.932 € | 6400 € | 6533 € | 179.292 € |
| 12 | 12.932 € | 6167 € | 6765 € | 172.527 € |
| 13 | 12.932 € | 5927 € | 7006 € | 165.521 € |
| 14 | 12.932 € | 5678 € | 7255 € | 158.266 € |
| 15 | 12.932 € | 5420 € | 7513 € | 150.753 € |
| 16 | 12.932 € | 5152 € | 7780 € | 142.973 € |
| 17 | 12.932 € | 4876 € | 8057 € | 134.916 € |
| 18 | 12.932 € | 4589 € | 8343 € | 126.573 € |
| 19 | 12.932 € | 4292 € | 8640 € | 117.932 € |
| 20 | 12.932 € | 3985 € | 8947 € | 108.985 € |
| 21 | 12.932 € | 3667 € | 9266 € | 99.719 € |
| 22 | 12.932 € | 3337 € | 9595 € | 90.124 € |
| 23 | 12.932 € | 2996 € | 9937 € | 80.187 € |
| 24 | 12.932 € | 2643 € | 10.290 € | 69.897 € |
| 25 | 12.932 € | 2277 € | 10.656 € | 59.242 € |
| 26 | 12.932 € | 1898 € | 11.035 € | 48.207 € |
| 27 | 12.932 € | 1505 € | 11.427 € | 36.779 € |
| 28 | 12.932 € | 1099 € | 11.834 € | 24.945 € |
| 29 | 12.932 € | 678 € | 12.255 € | 12.691 € |
| 30 | 12.932 € | 242 € | 12.691 € | 0 € |
Why you pay more interest than principal at the start
Under the French amortisation system — the most common in Spain — the monthly payment stays constant throughout the loan. However, the split between interest and principal is not constant: at the start almost everything is interest (calculated on a high outstanding balance) and very little principal; at the end it is the reverse.
This explains why if you sell or repay early in the first years, the outstanding balance has barely decreased from the original. It is also why early overpayments have such a large impact: every extra euro directly reduces the balance on which future interest is calculated.
How to use the mortgage calculator
Enter the property price and down payment and the calculator will automatically compute the loan amount. Select whether the property is new (VAT 10%) or second-hand (transfer tax by region) to include taxes in the summary. If you prefer not to include taxes, select that option.
Adjust the interest rate and term to see how the monthly payment changes. Try reducing the term: the payment rises but total interest falls significantly. Or extend the term: the payment drops but total cost increases considerably.
The chart shows the annual evolution of interest paid versus principal repaid. Hover over it to see exactly how much you pay in interest and principal each year, and the outstanding balance remaining.
How is a mortgage payment calculated?
The monthly mortgage payment is calculated using the French amortisation system, which is standard in Spain for fixed-rate mortgages. The formula takes into account three variables: the loan amount (outstanding principal), the monthly interest rate (annual rate divided by 12), and the number of payments (years multiplied by 12). The result is a constant payment throughout the life of the loan.
What does vary month by month is the composition of that payment: at the start most of it is interest, calculated on a high outstanding balance, and a small part repays principal. As the loan is paid off, the balance decreases, the interest component of each payment also falls, and the principal component grows. In the last month almost the entire payment is principal. This effect is what the calculator chart shows.
How the interest rate affects total cost
The interest rate has an enormous impact on the total cost of a mortgage. For a €200,000 loan over 30 years, the difference between a 2.5% rate and a 4.5% rate amounts to more than €90,000 in additional interest. This is why a small improvement in loan conditions can have very significant financial impact over the long term.
When comparing mortgage offers, pay attention not only to the nominal interest rate (TIN) but also to the APR (TAE in Spanish), which includes fees and other costs associated with the loan. The APR allows you to compare the true cost between different offers on equal terms.
How the loan term affects payment and total cost
Extending the term reduces the monthly payment but raises the total interest cost significantly. For a €200,000 loan at 3.5%, going from 20 to 30 years reduces the monthly payment by around €250 but costs more than €40,000 in additional interest. The choice between a short and long term depends on monthly affordability and the total financial cost you are willing to accept.
A common strategy is to take the longest term available to minimise the required monthly payment, then make overpayments when financially possible. This reduces the outstanding balance (and future interest) without committing to a high fixed payment from the start.
Frequently asked questions about mortgages
How is a mortgage payment calculated?
The monthly payment is calculated using the French amortisation formula: payment = P × r × (1 + r)ⁿ / ((1 + r)ⁿ - 1), where P is the principal, r is the monthly interest rate (annual / 12), and n is the total number of payments (years × 12). This formula ensures the payment is constant and the loan is fully repaid at the end of the term.
How much can I afford to pay on a mortgage?
The general recommendation is that the mortgage payment should not exceed 30–35% of the household's net monthly income. Above this threshold, debt levels are considered high and may compromise savings capacity. Banks typically require the payment to be no more than 40% of income before approving the loan, though criteria vary by lender.
Why do I pay more interest at the beginning of the mortgage?
Because interest is calculated each month on the outstanding balance. At the start the balance is at its maximum (the full loan amount), so the interest for that month is very high. As you repay principal, the balance falls and so does the interest. The constant-payment system (French amortisation) means this reduction in interest is offset by an increase in the principal component of the payment.
What is the difference between TIN and TAE (nominal rate vs APR)?
The TIN (nominal interest rate) is the pure loan rate, without including other costs. The TAE (annual equivalent rate, or APR) incorporates the TIN plus arrangement fees, management costs, and other costs linked to the loan, expressed as an annual rate. The TAE is the correct indicator for comparing the true cost of different mortgages, as it puts them on equal footing.
How much is the transfer tax (ITP) on a second-hand property in Spain?
The Impuesto de Transmisiones Patrimoniales (ITP) varies by autonomous community. The most common general rate ranges from 6% (Madrid, Navarre) to 10% (Catalonia, Cantabria, Galicia, Valencia). The calculator automatically applies your community's rate when you select a second-hand property.