Frequently Asked Questions
Quickly find answers to your questions about our simulators, real estate taxation and using the platform.
Last updated: March 2026
Getting Started
6 questionsMon Simulateur Immobilier is a comprehensive platform that allows you to analyze the profitability of your real estate investments. Here's how it works:
1. Choose a simulator from the 14 available (rental, life annuity, apartment building, etc.)
2. Enter the information of your project (price, rent, charges, taxation...)
3. Get instantly a detailed analysis with profitability, cash-flow and projections
4. Compare scenarios and optimize your tax strategy
5. Export to PDF to keep or share your analyses
2. Enter the information of your project (price, rent, charges, taxation...)
3. Get instantly a detailed analysis with profitability, cash-flow and projections
4. Compare scenarios and optimize your tax strategy
5. Export to PDF to keep or share your analyses
All calculations are based on current French tax legislation and official rates.
See also
No, most of our simulators work without an account. A few (commercial, holding, dismemberment, OBO…) require a free account to display their detailed results, and creating an account brings several advantages:
- Saving your simulations, with an automatic draft while you fill them in
- Complete history of your analyses
- Comparison between multiple projects
- PDF export of your simulations
- Access to advanced features
Creating an account is quick (less than 30 seconds) and completely free.
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Our platform covers all types of real estate investments:
Classic rental investment
- Unfurnished rental (property income)
- Furnished rental (LMNP/LMP)
- Apartment building
Alternative investments
- Life annuity (occupied, free, without annuity)
- Commercial property
- Parking and garages
Advanced structures
- Real estate holding
- Property dismemberment
- OBO (Owner Buy Out)
- Buy-sell (property dealer)
Optimization
- Rental deficit
- Energy renovation and renovation budget
- Solar panels
- Bank file
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Yes, entirely — with no calculation limit.
Everything is included
- Access to every published simulator and calculator
- Simulations and PDF exports with no cap
- Up to 50 saved simulations at the same time
- Personalized recommendations and comparisons
A free account — still no credit card — additionally unlocks the detailed results of some simulators (commercial, holding, dismemberment, OBO…), PDF and CSV export, and saving your simulations so you can find and compare them.
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Our property valuation tool calculates the market value of your property for free, based on real sales data:
How it works
- Enter the address, surface area, property type and its characteristics
- The tool positions your property using the median sale prices of its area (DVF data from the French tax authority, aggregated by the CSTB's BDNB at neighbourhood then municipality level)
- It derives an adjusted price per m², then an honest valuation range
What is taken into account
- Recent transactions in the same area (town, and even neighborhood/IRIS)
- The property type (apartment, house) and surface area
- The condition, floor and the green value linked to the energy rating (discount for energy-inefficient properties)
Important: the estimate is indicative and based on median sale prices per area; it does not replace the opinion of a real estate agent or notary, but provides a reliable range to position your property.
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Mon Simulateur Immobilier offers several decisive advantages over a spreadsheet:
Reliability
- Formulas verified and automatically tested
- Tax scales always up to date (marginal tax rate, social contributions, etc.)
- No risk of formula errors or broken cells
Time savings
- Instant results vs hours of spreadsheet configuration
- Complex tax cases (LMNP, rental deficit, holding) pre-calculated
- Professional PDF export in one click
Intelligence
- Automatic tax optimization
- Multi-scenario comparison
- Alerts on input errors and inconsistencies
A spreadsheet can be useful for very specific cases, but for standard real estate analysis, Mon Simulateur Immobilier is more reliable and faster.
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Calculations and reliability
5 questionsYes, our calculations are based on official sources and regularly updated:
Sources used
- French Tax Code (CGI)
- Official tax scales (marginal tax rate, social contributions)
- INSEE mortality tables (for life annuity)
- Official indices (IRL, ILC, ILAT)
- Notary fees by department
Calculation accuracy
- Rounded to 2 decimals for display
- Intermediate calculations at maximum precision
- Cross-validation of results
- Automated tests on formulas
Important: Our simulations are indicative and do not replace the advice of a professional (notary, accountant, wealth advisor).
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Net profitability takes into account all real financial flows:
Basic formulaNet profitability = (Net income - Charges - Taxes) / Total investment × 100
Income taken into account
- Annual rents
- Charge recovery
- Tax benefits (tax reductions)
Deducted charges
- Property tax
- Non-recoverable co-ownership charges
- PNO insurance
- Management fees
- Maintenance work
- Loan interest
Total investment
- Purchase price
- Notary fees
- Agency fees
- Renovation work
- Bank file fees
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Cash-flow represents the money that remains (or is missing) each month:
Gross cash-flow= Rents - Monthly loan payment
This is the cash before taxes and charges.
Net cash-flow= Rents - Monthly payment - Charges - Taxes/month
This is what actually remains in your pocket.
Concrete example
- Rent: €800/month
- Loan payment: €650
- Monthly charges: €100
- Monthly tax: €80
Gross cash-flow = 800 - 650 = +€150
Net cash-flow = 800 - 650 - 100 - 80 = -€30
Net cash-flow = 800 - 650 - 100 - 80 = -€30
A positive net cash-flow means the investment is fully self-financing.
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The IRR is calculated using the Newton-Raphson method:
PrincipleThe IRR is the discount rate that sets the NPV (Net Present Value) of all project cash flows to zero.
Cash flows included
- Initial contribution (negative flow)
- Net annual cash flows
- Estimated resale value (final positive flow)
- Net capital gain after taxes
Precision
- Convergence in 100 iterations maximum
- Converges as soon as the rate moves by less than 0.01 point, result shown to 2 decimals
- Handles cases without solution (negative IRR, irregular flows)
Difference with net profitabilityNet profitability is a simple annual ratio. IRR integrates the time dimension: it values one euro received today more than one euro received in 10 years.
IRR is the preferred indicator for professionals to compare investments of different durations.
See also
Notary fees are calculated according to official current schedules:
Fee composition
- Transfer duties: 6.32% in 89 departments (departmental share raised to 5.00% by art. 116 of the 2025 Finance Act), 5.81% in the 11 departments at 4.50% — including Mayotte since 1 June 2026 — and 5.09% in Indre alone, the only department still on the 3.80% statutory default
- Notary emoluments: regulated degressive schedule
- Disbursements: fees advanced by the notary (cadastre, mortgages...)
- VAT: on emoluments and formalities
Special cases
- New construction (VEFA): a 0.715% land registration tax instead of transfer duties — around 2 to 3% of total notary fees
- Property dealers: reduced duties if commitment to resell within 5 years (art. 1115 CGI)
Degressive emolument schedule (art. A444-91 Commercial Code)
- 0 to €6,500: 3.870%
- €6,500 to €17,000: 1.596%
- €17,000 to €60,000: 1.064%
- Above €60,000: 0.799%
Most of our simulators automatically apply the rate for the selected department; the rental profitability simulator starts from an overall rate pre-filled at 7.5%, which you can adjust.
See also
Tax questions
5 questionsLMNP (Non-Professional Furnished Rental) is a tax-advantageous status for furnished rentals:
Conditions
- The property must be furnished according to the legal list
- You remain non-professional as long as your furnished rental income stays below €23,000/year or below your other earned income — both thresholds must be crossed to become a professional lessor (art. 155 IV 2° of the French Tax Code)
Tax advantages
- 50% allowance under micro-BIC (income < €77,700)
- Deduction of actual charges under the real regime
- Depreciation of the property and furniture (major advantage)
- Carry-forward of deficits on future BIC income
What our simulator computesComponent-based depreciation of the building (structure, facade, technical installations, fixtures), excluding the land share — 15% by default, adjustable. Depreciation cannot create a loss: the excess is carried forward indefinitely.
Our simulator accurately calculates the LMNP advantage vs unfurnished rental. Simulate a LMNP investment
See also
The rental deficit allows you to deduct your renovation costs from your income:
PrincipleWhen your charges (including works) > rental income, you create a deficit that can be charged against your overall income.
Limits
- €10,700/year maximum against overall income (art. 156-I-3° of the French Tax Code), raised to €21,400 for F or G rated properties whose works reach A, B, C or D — work paid for until 31/12/2027 (scheme refocused and extended by the 2026 Finance Act)
- Surplus carried forward for 10 years against rental income
Deductible charges
- Maintenance and repair work
- Improvement work
- Loan interest (only against rental income)
- Management fees, insurance
Non-deductible work
- Construction / extension
- Reconstruction
Our simulator optimizes the timing of your work to maximize the tax advantage. Simulate a rental deficit
See also
The choice of tax regime for the SCI has a major impact on profitability:
SCI under Income Tax (IR) — default regime
- Rental income taxed at the progressive scale (marginal rate + 17.2% social contributions)
- Rental deficit chargeable against overall income (€10,700/year, €21,400 for an F or G property renovated to A, B, C or D)
- Individual capital gains on resale (allowances for holding period)
- Full exemption after 30 years of ownership
SCI under Corporate Tax (IS) — irrevocable option
- Taxation at reduced IS rate: 15% up to €42,500 then 25%
- Property depreciation (like LMNP) — significant reduction of taxable income
- Financial charges fully deductible
- Professional capital gains on resale (no holding period allowance)
When to choose IS?
- High marginal tax rate (≥ 30%)
- Capitalization strategy (no distribution)
- Holding with multiple properties
- Long-term wealth objective
See also
Yes, all our simulators include current social contributions:
Current rates (2026, 2026 Social Security Financing Act — Law no. 2025-1403 of 30 December 2025)
- Unfurnished rental income and real estate capital gains: 17.2% (CSG 9.2% + CRDS 0.5% + solidarity levy 7.5%)
- Furnished rental income (LMNP/LMP), dividends and interest: 18.6% (CSG raised to 10.6%)
Application by regime
- Rental income (unfurnished): 17.2% on net rental income
- BIC (LMNP/LMP): 18.6% on net profit
- Real estate capital gains: 17.2% after holding period allowances
- SCI under IS: no social contributions at company level, 18.6% on distributed dividends
Deductible CSG6.8% for unfurnished rental income, 8.2% for capital and furnished rental income (art. 154 quinquies CGI).
Our simulators automatically calculate the exact amount of social contributions based on your situation.
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Real estate capital gains are taxed on the resale of the property:
Gross capital gain calculationSale price - Purchase price (increased by fees)
Fees increasing the purchase price
- Actual acquisition costs or, for a property bought (not received by gift or inheritance), a flat rate of 7.5% of the price
- Actual works (with proof) or, for a building owned for more than five years, a flat rate of 15% of the price
- Each flat rate is an option: the more favourable amount applies (art. 150 VB II of the French tax code)
Holding period allowances
- Income tax (19%): full exemption after 22 years
- Social contributions (17.2%): full exemption after 30 years
Surtax on high capital gainsFrom 2% to 6% for net capital gains > €50,000 (art. 1609 nonies G CGI)
Exemptions
- Primary residence: full exemption
- First sale of a property other than the primary residence (subject to conditions)
- Sale price < €15,000
See also
Advanced structures
3 questionsOur holding simulator models complex corporate structures:
Typical structureHolding company (SAS/SARL under IS) → Subsidiary SCI(s) under IS
Modeled advantages
- Parent-subsidiary regime: 95% exemption on remitted dividends (art. 145 and 216 CGI)
- Tax integration: offsetting results between companies
- Leverage effect: borrowing at holding level to acquire shares
- Optimized cash flow: cash centralization
What the simulator calculates
- Tax result for each entity
- Dividend flows and cash agreement
- Corporate tax at each level
- Overall net profitability of the structure
See also
Dismemberment separates ownership into two distinct rights:
Usufruct — right to use and collect income
Bare ownership — right to dispose of the property
Bare ownership — right to dispose of the property
Valuation (tax scale art. 669 CGI)
- Usufructuary < 21 years: usufruct = 90%, bare ownership = 10%
- Usufructuary 21-30 years: usufruct = 80%, bare ownership = 20%
- Usufructuary 41-50 years: usufruct = 60%, bare ownership = 40%
- Usufructuary 61-70 years: usufruct = 40%, bare ownership = 60%
- Usufructuary aged 91 and over: usufruct = 10%, bare ownership = 90%
Advantages of dismemberment
- Transmission: donation of bare ownership at reduced tax cost
- IFI: bare owner is not liable for IFI on the property
- Optimization: reconstitution of full ownership at usufructuary's death without inheritance tax
See also
The OBO allows you to "buy yourself back" a property through a corporate structure:
Principle1. You own a property in your own name
2. You create an SCI (often under IS)
3. The SCI buys the property at market value
4. The SCI finances the acquisition through bank borrowing
5. You recover cash while maintaining control
2. You create an SCI (often under IS)
3. The SCI buys the property at market value
4. The SCI finances the acquisition through bank borrowing
5. You recover cash while maintaining control
Advantages
- Cash: recovery of cash without actually selling
- Capital gain: purging of latent capital gain (primary residence exemption possible)
- Depreciation: the SCI under IS can depreciate the repurchased property
- Transmission: gradual donation of SCI shares
Key considerations
- The transaction must have economic substance (no abuse of law)
- Notary fees and transfer duties on the sale
- Loan to be obtained in the name of the SCI
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Account and subscription
2 questionsCreating an account is simple and fast:
1. Click on "Create an account" at the top right
2. Enter your email and choose a password
3. Validate your email via the link received
4. Your account is active!
2. Enter your email and choose a password
3. Validate your email via the link received
4. Your account is active!
Alternative loginYou can also connect with:
Data collected
- Email (for login and notifications)
- Saved simulations
- Usage preferences
Your data is protected and never sold. Check our privacy policy.
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The security of your data is our priority:
Infrastructure
- Secure hosting (Supabase/AWS)
- Data encryption in transit (TLS 1.3)
- At-rest disk encryption provided by Supabase (AES-256 on AWS/GCP) — note: no client-side application-level encryption, data remains readable in plaintext via the authenticated API
- Row-Level Security access control (Supabase RLS)
- Daily backups
Authentication
- Hashed passwords (bcrypt)
- Secure sessions
- Rate-limited sign-in with temporary lockout after repeated failures
Compliance
- GDPR compliant
- Transfers outside the European Union governed by standard contractual clauses
- No data resale
- Right to erasure respected
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Features
3 questionsYour simulations are kept as soon as you save them:
Saving a simulation
- Click "Save" at the end of the simulation (account required)
- Give it a name so you can find it easily
- While you are logged in, a draft of the current simulation is kept automatically
Find a simulation1. Go to Dashboard
2. Section "My simulations"
3. Filter by type or search by name
4. Click to open and modify
2. Section "My simulations"
3. Filter by type or search by name
4. Click to open and modify
Available actions
- Modify and recalculate
- Export to PDF
- Delete
How many can I save?
- Up to 50 simulations. Beyond that, delete one to save a new one.
See also
PDF export generates a professional report:
PDF content
- Investment summary
- Financial flows table
- Profitability charts
- Projection over chosen duration
- Tax detail
- Personalized recommendations
Procedure1. Complete your simulation
2. Click on "Export PDF" (account required)
3. The PDF downloads automatically — it carries a "Free" watermark on the free plan
2. Click on "Export PDF" (account required)
3. The PDF downloads automatically — it carries a "Free" watermark on the free plan
Uses
- Presentation to your banker
- File for your notary
- Personal archives
- Sharing with an advisor
See also
The bank file simulator prepares your financing application:
Information analyzed
- Your current income and expenses
- Your debt ratio (before and after the project)
- The "remaining to live" per household member
- Your personal contribution
Results provided
- Maximum borrowing capacity
- Projected debt ratio (HCSF limit: 35%)
- Monthly payment amounts by duration
- Total cost of credit
- Recommendation on financing structure
Modeled banking criteria
- Income weighted by type (rental income and bonuses at 70%, investment income at 50%, salaries and pensions at 100%)
- Minimum remaining-to-live by household composition
- Estimated borrower insurance
See also
Technical questions
4 questionsHere are the troubleshooting steps:
1. Basic checks
- Refresh the page (F5 or Ctrl+R)
- Clear browser cache
- Try in private browsing
- Test with another browser
2. Connection
- Check your internet connection
- Temporarily disable your VPN
- Disable ad blockers
3. Supported browsers
- Chrome (recommended)
- Firefox
- Safari
- Edge
- Recent versions only
4. Persistent problem?Contact us via the contact form specifying:
- Browser used
- The action that causes the problem
- A screenshot if possible
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Yes, Mon Simulateur Immobilier is optimized for all screens:
Responsive web
- Works on smartphone and tablet
- Interface adapted to small screens
- All features available
Mobile application
- No native app for now
- Add the site as a shortcut to your home screen
- It then opens full-screen, like an app (internet connection required)
SynchronizationYour simulations are synchronized across all your devices connected to the same account.
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It depends on your situation:
With an account
- Yes, all your simulations are saved server-side
- You can find them on any browser or device
- Just log in with the same account
Without an account
- Current simulations are stored in the browser (localStorage)
- They are not transferable between browsers
- They may be lost if you clear the cache
RecommendationCreate a free account to never lose your simulations. It's quick and secure.
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We appreciate your feedback to improve the platform:
Report a bug
- Use the contact form with the subject "Bug"
- Describe the steps to reproduce the problem
- Attach a screenshot if possible
- Specify your browser and device
Suggest an improvement
- Same form, subject "Suggestion"
- Describe the use case you would like to see covered
- We prioritize the most frequent requests
We read every report and get back to you as soon as we can.
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