Calculate the new rent
Indices published by INSEE, the French statistics office: ILC (retail and commercial activities) and ILAT (office activities).
Result
Enter all three amounts to see the result.
The latest ILC and ILAT values
The calculation uses the index named in the lease, for the reference quarter and the review quarter. The last eight values published by INSEE, the French statistics office, are set out below. Over one year, the ILC for the 2nd quarter of 2026 is up 0.26% and the ILAT 0.63%.
Quarterly values published by INSEE
| Quarter | ILC | ILAT |
|---|---|---|
| Q2 2026 | 137.16 | 138.01 |
| Q1 2026 | 135.26 | 137.42 |
| Q4 2025 | 134.62 | 137.21 |
| Q3 2025 | 137.09 | 137.07 |
| Q2 2025 | 136.81 | 137.15 |
| Q1 2025 | 135.87 | 137.29 |
| Q4 2024 | 135.30 | 137.29 |
| Q3 2024 | 137.71 | 137.12 |
Source: INSEE, ILC base 100 in Q1 2008 and ILAT base 100 in Q1 2010, values checked on 8 November 2026. The Q2 2026 values were published in September 2026.
For earlier quarters, see the full ILC history and the ILAT history since 2005.
How to calculate commercial rent indexation
The new rent equals the current rent multiplied by the new index, divided by the reference index. Use the index set in the lease: the commercial rent index (ILC) for retail, commercial and craft activities, or the office activities rent index (ILAT) for office use.
Both values must come from the same index. The reference quarter is the one set by the lease clause, or the quarter of the last rent set; the new index is the value for the quarter matching the review date.
Worked example, with made-up values
| Item | Value |
|---|---|
| Current annual rent | €24,000 excluding VAT |
| Reference index (made up) | 130.00 |
| New index (made up) | 133.90 |
| Calculation | 24,000 × 133.90 ÷ 130.00 |
| New annual rent | €24,720 excluding VAT |
| Change | +3.00% |
| Difference | €720 a year, or €60 a month |
These index values are made up for the example. Always use the values published by INSEE.
Indexation or three-yearly review: what is the difference
An indexation clause, also called a sliding scale clause, is written into the lease: the rent changes automatically, usually every year, in line with the chosen index. No request is needed, but the calculation must follow the exact wording of the clause.
The three-yearly review is set by law and applies even without a clause: the landlord or the tenant can request it every three years, under the conditions of article L. 145-38 of the Commercial Code. It does not apply automatically and requires a request.
How the two mechanisms interact depends on how the lease is drafted. If you are unsure about the clause, the reference quarter or a large change, have the lease reviewed before sending a request or accepting a new rent.
ILC or ILAT: which index applies to your lease
French law allows two indices for business premises. The ILC applies to commercial or craft activities defined by decree; the ILAT applies to other activities and to the liberal professions (article L. 112-2 of the Monetary and Financial Code).
In practice, use the index named in the indexation clause of your lease, for the quarter it specifies. If the lease names the wrong index for the business carried on, or does not specify the reference quarter, have the clause reviewed before you calculate anything.
Commercial rent increases: the cap and the 10% annual limit
On a three-yearly review, the increase or decrease cannot exceed the change in the ILC or ILAT since the rent was last set by agreement or by the court. The exception is where a material change in local trading conditions has, on its own, changed the rental value by more than 10%; even then, the resulting increase cannot exceed, in any one year, 10% of the rent paid the previous year (article L. 145-38 of the Commercial Code).
The same annual limit applies to a review requested because an escalation clause has moved the rent by more than a quarter: the increase cannot exceed 10% of the previous year's rent, for leases signed or renewed since 1 September 2014 (article L. 145-39). The calculator shows the raw change; it does not apply this limit, which depends on your situation.
How to request a rent review
The three-yearly review does not happen automatically: the landlord or the tenant must request it, no earlier than three years after the tenant moved in or the renewed lease started, and then every three years (article L. 145-38 of the Commercial Code).
The request is served by a judicial officer or sent by registered letter with acknowledgement of receipt. It must state the rent requested or offered, failing which it is void. The new rent is due from the date of the request; if the parties cannot agree, the court sets it (article R. 145-20 of the Commercial Code).
New in 2026: clauses that limit changes in the ILC
Since 28 May 2026, a commercial lease may contain a clause that limits, by the same proportion upwards and downwards, the annual change in the ILC used for rent reviews (article L. 145-38-1 of the Commercial Code, created by Law No. 2026-403 of 26 May 2026).
If your lease contains such a clause, the reviewed rent may differ from the raw result of the calculator: apply the limit set by the clause first, or have the calculation checked.
Questions about commercial rent reviews in France
When can the rent under a French commercial lease be reviewed?
In three ways: every year if the lease has an indexation clause, every three years through the statutory three-yearly review (article L. 145-38 of the Commercial Code), and at any time if an escalation clause has moved the rent by more than a quarter compared with the last rent set (article L. 145-39).
Can the rent go down?
Yes. The law refers to an increase or a decrease on a three-yearly review (article L. 145-38), and the indices can fall from one quarter to the next: the ILC went from 137.09 in Q3 2025 to 134.62 in Q4 2025.
Which reference quarter should I use?
For indexation, the quarter named in the lease clause. For a three-yearly review, the change is measured from the last time the rent was set by agreement or by the court (article L. 145-38).
How do I request a review?
By a document served by a judicial officer or by registered letter with acknowledgement of receipt, stating the rent requested or offered, failing which the request is void. The new rent is due from the date of the request (article R. 145-20 of the Commercial Code).
Does the calculator apply the 10% limit or a clause limiting the ILC?
No. It gives the raw change between the two index values. The 10% annual limit and any clause limiting the ILC depend on your lease and your situation, so the result is for guidance only.