You are selling a flat bought twelve years ago, and when the time comes to sign at the notary's office, you discover that part of your gain goes to tax. The real estate capital gain — the difference between the sale price and the purchase price — is taxed at an overall rate of 36.2% (19% income tax and 17.2% social charges), before any allowance. On an €80,000 gain, that comes to nearly €29,000 if the property has been held for a short time.
The good news: the holding-period allowance system reduces the bill year after year, all the way to a full exemption. But the calculation hides several pitfalls — uplifting the purchase price, the surtax on large gains, and, since 2025, the add-back of depreciation for furnished landlords. This article explains the real estate capital gains 2026 calculation line by line, with a full worked example.
Full income-tax exemption after 22 years of ownership, and full social-charge exemption after 30 years — the so-called "17-year" reform was not adopted: the reference periods remain unchanged in 2026.
What this article covers
You will find here the complete mechanism for calculating individuals' real estate capital gains in 2026: the taxable base (sale price minus purchase price, uplifted by acquisition costs and works), the tax rates, the holding-period allowance schedule, the progressive surtax above €50,000, exemptions (notably the main residence), and the specific case of the non-professional furnished landlord (LMNP) since the 2025 Finance Act. A worked example details each line.
The legal framework for real estate capital gains in 2026
Individuals' real estate capital gains are governed by articles 150 U to 150 VH of the French General Tax Code (CGI — Code Général des Impôts). The principle is set out in CGI article 150 U: the disposal for consideration of a property, or of rights relating to a building, generates a taxable capital gain, save in cases of exemption. The tax is assessed and paid by the notary when the authenticated deed of sale is signed, then remitted to the public treasury.
Taxation breaks down into two distinct components, which follow different allowance schedules. On one side, income tax at the flat rate of 19% (CGI art. 200 B). On the other, social charges (CSG-CRDS — Contribution Sociale Généralisée and Contribution au Remboursement de la Dette Sociale, plus the solidarity levy) at the overall rate of 17.2% (CGI art. 1600-0 G et seq.). The combined gross rate therefore reaches 36.2%.
| Item | Rate / rule | Legal reference |
|---|---|---|
| Income tax | 19% flat | CGI art. 200 B |
| Social charges (CSG-CRDS) | 17.2% | CGI art. 1600-0 G et seq. |
| Surtax on high capital gains | 2% to 6%, progressive above €50,000 | CGI art. 1609 nonies G |
| Main-residence exemption | Full | CGI art. 150 U II 1° |
| Holding-period allowance | Income-tax exemption at 22 years, social charges at 30 years | CGI art. 150 VC |
One point to watch for 2026: a reform discussed during the budget debates would have aligned the full exemption (income tax and social charges) on a single 17-year period. This so-called "17-year" reform was not adopted. The reference periods therefore remain 22 years for income tax and 30 years for social charges. Any calculation based on a 17-year exemption would be wrong.
The main residence escapes this mechanism entirely: the capital gain realised on its sale is exempt (CGI art. 150 U II 1°), provided the dwelling is the seller's main residence on the day of disposal. The reference sources for these rules are service-public.gouv.fr (fact sheet F10864), impots.gouv.fr and the Official Bulletin of Public Finances (BOFiP).
How to calculate the taxable capital gain step by step
The calculation unfolds in four stages: determine the gross capital gain, uplift the purchase price, apply the holding-period allowances, then assess the tax and any surtax. Each stage follows precise CGI rules.
1. The gross capital gain: sale price minus uplifted purchase price
The gross capital gain is the difference between the disposal price and the purchase price. The disposal price (CGI article 150 VA) corresponds to the actual price stated in the deed, less the costs borne by the seller (for example the mandatory diagnostics or the costs of releasing a mortgage).
The purchase price (CGI article 150 VB) can be uplifted, which reduces the taxable capital gain. Two flat-rate upticks exist and avoid having to produce supporting documents:
- Acquisition costs: a flat 7.5% of the purchase price, or the actual amount on supporting documents (notary fees, registration duties).
- Works: a flat 15% of the purchase price if the property has been held for more than five years, or the actual amount of improvement, construction or extension works on invoices from companies (maintenance works and amounts already deducted for tax purposes are not taken into account).
Profile: an owner who has insulated and renovated an older flat has every interest in comparing the 15% flat rate with the actual invoices: if the works exceed 15% of the purchase price, the actual amount is more favourable and reduces the taxable capital gain further.
2. The holding-period allowance
The gross capital gain is then reduced by an allowance that increases with the holding period (CGI article 150 VC), calculated separately for income tax and for social charges. The rates differ, which is why full exemption is reached on different dates.
| Holding period | Income-tax allowance (19%) | Social-charge allowance (17.2%) |
|---|---|---|
| Up to the 5th year | 0% | 0% |
| From the 6th to the 21st year | 6% per year | 1.65% per year |
| 22nd year | 4% (balance: full exemption) | 1.60% |
| From the 23rd to the 30th year | Already exempt | 9% per year |
| Beyond 30 years | Exempt | Exempt |
In practice, the income-tax exemption is reached after 22 years (16 years at 6% = 96%, plus 4% in the 22nd year). The social-charge exemption is far slower: 16 years at 1.65% then 1.60% in the 22nd year give only a 28% allowance at 22 years; you have to wait until the 30th year (with 9% per year from the 23rd to the 30th) to reach 100%.
3. The surtax on high capital gains
Above a certain amount, a surtax applies (CGI article 1609 nonies G). It applies to the taxable capital gain — that is, after the holding-period allowance — when it exceeds €50,000. The rate is progressive, from 2% to 6%, according to brackets set by the statutory schedule. The surtax therefore does not affect properties heavily reduced by long ownership, even where the gross gain is large.
Worked example: calculating the capital gain on a flat
Let us take an illustrative example based on realistic market orders of magnitude (price references drawn from the DVF database and the Notaires de France data). You bought a 58 m² flat in 2008 in a large provincial city for €187,000, and you sell it in 2026 for €312,000. You carried out €24,000 of improvement works supported by invoices. The holding period is 18 full years.
Scenario — sale in 2026 after 18 years of ownership
| Item | Calculation detail | Amount |
|---|---|---|
| Disposal price | Net sale price | €312,000 |
| Purchase price | 2008 purchase price | €187,000 |
| Acquisition costs (7.5% flat rate) | 187,000 × 7.5% | €14,025 |
| Works (actual, on invoices) | Higher than the 15% flat rate | €24,000 |
| Uplifted purchase price | 187,000 + 14,025 + 24,000 | €225,025 |
| Gross capital gain | 312,000 − 225,025 | €86,975 |
At 18 years of ownership, the allowance covers years 6 to 18, i.e. 13 full years. For income tax: 13 × 6% = 78% allowance. For social charges: 13 × 1.65% = 21.45% allowance.
| Item | Calculation detail | Amount |
|---|---|---|
| Income-tax base | 86,975 × (1 − 78%) | €19,134 |
| Income tax (19%) | 19,134 × 19% | €3,635 |
| Social-charge base | 86,975 × (1 − 21.45%) | €68,320 |
| Social charges (17.2%) | 68,320 × 17.2% | €11,751 |
| Total taxation | Income tax + social charges | €15,386 |
The income-tax base (€19,134) stays below €50,000, so no surtax applies. On a gross gain of €86,975, the effective taxation comes to around 17.7% thanks to the holding-period allowance — well below the 36.2% theoretically applicable before any allowance. This example is purely illustrative: your situation depends on the exact acquisition date, the works invoices, and any applicable exemptions.
Common mistakes in the capital gains calculation
Mistake 1 — Forgetting to uplift the purchase price
Many sellers calculate their capital gain on the bare gap between purchase price and sale price, without including the 7.5% flat acquisition-cost rate or the works. Yet these upticks directly reduce the taxable base. In our example, they lower the gross capital gain by €38,025, which is several thousand euros of tax saved. Keep all your invoices from RGE-certified companies (Reconnu Garant de l'Environnement) and your notarial deeds.
Mistake 2 — Counting in calendar years rather than full years of ownership
The allowance is calculated by 12-month periods elapsed since the acquisition date, not by calendar years. A property bought in June 2008 and sold in March 2026 counts 17 full years, not 18. Delaying the sale by a few months can cross an allowance threshold and reduce the tax. It is one of the rare perfectly legal optimisation levers.
Mistake 3 — Believing in a 17-year exemption
The so-called "17-year" reform circulated in the budget debates but was not voted into law. The periods applicable in 2026 remain 22 years for income tax and 30 years for social charges. Basing a decision to sell on an early exemption at 17 years would lead to a nasty surprise when the notary assesses the tax.
⚠️ Warning: since 15 February 2025 (2025 Finance Act), the depreciation deducted by a non-professional furnished landlord (LMNP — Loueur en Meublé Non Professionnel) is added back into the capital gains calculation on resale, excluding furniture. In practice, the purchase price retained is reduced by the depreciation taken, which increases the taxable capital gain. An LMNP investor who fails to provision for this effect significantly overestimates their net gain.
Mistake 4 — Confusing a main residence with a second home
The capital gains exemption applies only to the main residence on the day of disposal (CGI art. 150 U II 1°). A second home, a buy-to-let investment, or a long-vacant dwelling does not qualify for this automatic exemption. Selling a property you left several years ago without re-letting it can cause the loss of main-residence status.
Calculate your capital gain before selling
Mon Simulateur Immobilier real estate capital gains calculator
Estimate your net capital gain after the holding-period allowances and tax (19% income tax + 17.2% social charges), factoring in the uplifted purchase price, the works and any surtax above €50,000, based on your acquisition date and your sale price.
To go further: bare-ownership / usufruct split (démembrement) simulator and rental yield simulator.
Conclusion
The real estate capital gain is not a tax inevitability: the 36.2% gross rate falls mechanically with the holding period, all the way to a full income-tax exemption at 22 years and a full social-charge exemption at 30 years. The real levers lie in uplifting the purchase price (justified costs and works), in the timing of the sale relative to the allowance thresholds, and in knowing the exemption cases.
Before you set your price and your signing date, cost the operation precisely. The Mon Simulateur Immobilier real estate capital gains calculator incorporates the allowances, the surtax and the uplifted purchase price to give you your real net capital gain, and to avoid the costliest calculation errors.
