Mortgage simulator (France)

Build your financing plan with several loans and the loans you already repay: overall debt ratio, payments and costs per loan, per purchase and in total, smoothing, borrowing capacity and amortisation schedule.

Estimate, no sign-up. Everything is calculated in your browser: no data is sent and no broker will call you. Banks apply their own criteria (remaining savings, income stability, money left to live on).

Compare two scenarios

Loan by loan

Totals by purchase and overall

Repayments over time

Each colour is a loan; loans for other purchases are lighter. The red line is the maximum payment to stay below the chosen debt ratio.

Amortisation schedule

How to use the simulator

Your household: each borrower's net monthly income before tax (and other regular income), other commitments such as maintenance paid.
The purchase: price, notary fees (about 7.5% for existing homes, 2.5% for new builds), works, guarantee (about 1%), arrangement or broker fees and deposit. The amount to finance is calculated automatically.
Loans for the purchase: add as many loans as needed (main loan, PTZ zero-rate loan, employer loan, interest-only loan…) with amount, term, rate, insurance and any deferral. The “= remaining need” button sets a loan to close the plan.
Existing loans: group the loans you already repay by purchase (current home, buy-to-let, car…), with any rent received. Enter them by monthly payment or by their details (amount, rate, term, first payment); tick “Sell this property” for a buy-and-sell (bridging loan suggested) or “Buy out” to include them in the new loan.

Advanced features

PTZ: the amount is calculated from the zone, household size, reference taxable income and type of home (scale for offers issued since 1 April 2025, published by ANIL), with its term and deferral.
Insurance on the initial principal (fixed payment) or on the outstanding balance (decreasing), with the cover (100% for one borrower, 200% for two borrowers each insured at 100%).
Capped variable rate: fixed for a few years, then a yearly change limited by the cap; the payment is recalculated at each change.
Early repayment: a lump sum after a given payment, then a shorter term or a lower payment; fees of 3% of the amount repaid, capped at six months of interest (none for the PTZ).
Bridging and interest-only loans: only interest counts in the debt ratio, the principal being repaid by the sale or an investment.
Buy-to-let: gross and net yield, cash flow and monthly top-up; the expected rent is counted at 70% of income.
Two scenarios side by side, and a PDF file (summary, financing plan, loans, existing loans, amortisation schedule) to show a bank.

How it is calculated

Payment of a repayment loan of principal $C$, monthly rate $t$ (annual rate / 12), over $n$ months: $M = C \times \dfrac{t}{1 - (1+t)^{-n}}$; insurance (as a % of the initial principal per year) is added.
Deferral: partial, only interest is paid; full, nothing is paid and interest is added to the principal. The loan is then repaid over the remaining term.
Smoothing: the main loan's payment varies so that the total for the purchase stays constant, for example while the PTZ is deferred and then repaid.
Debt ratio: all loan payments, insurance included, plus other commitments, divided by net income before tax (rent counted at 70%). France's financial stability board (HCSF) caps it at 35% and the term at 25 years (27 for new builds with a deferral), except for exceptions on at most 20% of files.
APR (TAEG): the annual actuarial rate that equates the money actually received (loans minus guarantee and fees) with all payments, insurance included.

Frequently asked questions

Why does the “maximum” debt ratio differ from the one at the start?

When a loan has a deferral (often the PTZ) or an existing loan ends, payments change. The simulator finds the month with the highest payments: that is the figure the bank will look at. Smoothing keeps them constant.

Does the PTZ count in the debt ratio?

Yes, once it is being repaid; during a full deferral it only costs its insurance.

Is my data sent anywhere?

No. The simulator runs entirely in your browser, which keeps your last simulation; the share link contains the simulation itself.

A worked example

A loan of €200,000 over 20 years at 3.5% gives a monthly payment, excluding insurance, of about €1,160, and total interest of about €78,400. With borrower insurance at 0.30% of the capital per year, add €50 a month. To stay within a 35% debt-to-income ratio, insurance included, you need about €3,460 of net monthly income (with no other loans).

Over 25 years at the same rate, the payment drops to about €1,000, but interest rises to €100,400: €22,000 more.
At 3% instead of 3.5% over 20 years, the payment falls by about €50 and the saving exceeds €12,000 over the loan. Negotiating the rate (or using a broker) is worth it.

Rules to know (France)

Debt-to-income ratio: banks follow the HCSF recommendation of at most 35% of net income, insurance included, and a term of at most 25 years (up to 27 with a deferral in some cases, such as new builds). A share of files may exceed these limits, mainly for main residences.
Disposable income: beyond the percentage, banks look at what is left each month after loans; a high income handles 35% better than a modest one.
Notary fees: about 7.5% for existing homes, 2.5% for new builds, usually paid from your deposit.
Deposit: 10% of the price is often expected, at least enough to cover fees.

Several loans and smoothing

A zero-rate PTZ or an Action Logement loan is often repaid over a different term from the main loan, sometimes with a deferral. Left as is, the total monthly payment varies a lot over time. Smoothing adjusts the main loan so the overall payment stays constant, as banks do. The “payments over time” chart shows each loan in colour and the debt limit in red.

Getting the most from the simulator

Enter your existing loans (car, consumer credit): they count towards your debt ratio.
Compare two scenarios (term, deposit, price) side by side before deciding.
For a buy-to-let, enter the expected rent: banks usually count only 70% of it as income.
Export the amortisation table as CSV or the file as PDF for a bank meeting.

The simulator gives an estimate: the bank's loan offer, with its APR (TAEG), prevails.

Guide written and checked by Erwan Hautot · updated 2 November 2026.