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Mortgage Payments
FR
My Real Estate Simulator
FR

Mortgage Payment Calculator

Estimate your monthly mortgage payments with borrower insurance. Calculate the total cost of your loan in seconds.

How does the monthly payment calculation work?

🧮 The calculation formula

Calculating mortgage payments relies on the constant amortization formula. This formula takes into account three main elements: the borrowed amount (principal), the annual interest rate, and the loan duration. With each monthly payment, you repay part of the principal and interest calculated on the remaining balance.

Borrower insurance

Borrower insurance is mandatory and represents an additional cost. It covers risks of death, disability, or incapacity. Its cost, generally between 0.20% and 0.50% of the borrowed capital per year, varies according to your age, health status, and profession. In our calculator, insurance is calculated on the initial capital ("constant" insurance), which is the most common method.

Lemoine Law: switch insurance anytime

Since the Lemoine Law (2022), you can switch your borrower insurance at any time, with no fees or notice period. For loans under €200,000 per insured person repaid before age 60, the medical questionnaire is waived. This law also strengthens the right to be forgotten (reduced from 10 to 5 years) for former cancer and hepatitis C patients.

Total loan cost

The total loan cost includes the sum of interest paid over the entire loan duration and the total insurance cost. On a €250,000 loan at 3.5% over 20 years with 0.35% insurance, you will repay approximately €364,000 in total, i.e., €114,000 in costs (46% of the principal).

💡 Good to know

  • • The longer the loan duration, the higher the total interest cost
  • • Lemoine Law: you can switch your borrower insurance at any time, with no fees
  • • The maximum recommended debt ratio is 35% of gross income (HCSF rule)
  • • Processing fees (about 1% of the loan) are not included in this calculation

📊 Concrete example

€250,000 loan over 20 years at 3.5% with 0.35% insurance:

  • • Loan payment: €1,446.57
  • • Insurance payment: €72.92
  • • Total monthly payment: €1,519.49
  • • Total interest cost: €97,176
  • • Total insurance cost: €17,500
  • • Total repaid: €364,676

Frequently asked questions

1

How do I calculate my mortgage payments?

Mortgage payments are calculated using the constant amortization formula: M = C × (t/12) / [1 - (1 + t/12)^(-n)], where C is the borrowed capital, t is the annual interest rate, and n is the number of payments. To this is added the borrower insurance calculated on the initial capital.
2

What is borrower insurance?

Borrower insurance is a mandatory guarantee that protects the bank in case of death, disability, or incapacity of the borrower. Its cost, generally between 0.20% and 0.50% of the borrowed capital per year, is added to the loan payments.
3

What is the total cost of a mortgage?

The total cost of a mortgage includes interest paid over the entire loan duration and the cost of borrower insurance. On a €250,000 loan at 3.5% over 20 years, the total cost represents about €114,000, or 46% of the borrowed capital.
4

How do I know my debt ratio?

The debt ratio is calculated by dividing your monthly loan payments (including insurance) by your gross monthly income. Banks generally apply a maximum threshold of 35% according to HCSF (High Council for Financial Stability) recommendations.
5

What loan duration should I choose?

The loan duration directly impacts your monthly payments and total credit cost. A short duration (15 years) reduces interest costs but increases monthly payments. A long duration (25 years) decreases monthly payments but increases total cost. The choice depends on your repayment capacity and your project.
6

Can I exceed the 35% debt-to-income ratio?

HCSF rules set the maximum debt-to-income ratio at 35% of gross income (including insurance). However, banks have a flexibility margin: they can grant up to 20% of new loans above this threshold, of which 70% must go to primary residence purchases. A strong application (high income, comfortable remaining income, savings) may allow exceeding this limit.
7

What is the difference between initial capital and remaining balance insurance?

Initial capital (CI) insurance is calculated on the borrowed amount: the monthly insurance payment stays fixed throughout the loan. Remaining balance (CRD) insurance is recalculated each month on the outstanding balance: it starts higher then decreases gradually. Over the full loan term, CRD insurance is typically 10-20% cheaper overall, but its displayed rate is higher.
8

How does a deferred payment period work?

A deferral (or grace period) lets you postpone principal repayment at the start of the loan. With partial deferral, you pay only the interest each month. With total deferral, you pay nothing (interest is capitalized and added to the remaining balance). Deferral is common for off-plan purchases (VEFA, up to 2 years) but increases the total loan cost.
9

What is the usury rate and how do I know if my loan complies?

The usury rate is the legal maximum APR beyond which a bank cannot lend. It is set quarterly by the Banque de France and varies by loan duration and type. In Q1 2026, it is 5.13% for fixed-rate loans of 20 years or more. Your APR (which includes the nominal rate, insurance, and all fees) must remain below this threshold.

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Warning: The simulations presented on this site are provided for informational purposes only and do not constitute investment advice, a credit offer, or a recommendation to buy or sell. The results displayed are estimates based on the data provided and do not guarantee future performance. Any real estate investment decision should be made after consulting qualified professionals (notary, financial advisor, accountant, tax lawyer). The publisher disclaims any responsibility for decisions made based on these simulations.
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Loan parameters
€

Total amount you wish to borrow

€10,000.00€2,000,000.00
%

Annual interest rate offered by your bank (average rate: 3.5%)

years

Loan repayment period (typically between 15 and 25 years)

1 yr30 years
%

Annual borrower insurance rate (average rate: 0.35%). Lemoine Law: you can switch insurance anytime, with no fees

Loan start date (first payment)

Deferred payment (optional)

Postpone all or part of the payments at the start of the loan

Fees (optional)