Reference Decision: cc • No. 12-13.962 • 2013-03-06 • View the decision →
Imagine you are the owner of commercial premises on Place Saint-Roch in Mont-de-Marsan. Your tenant, a restaurateur, is approaching the end of their lease. You negotiate the renewal and agree on a rent that will increase progressively over the next nine years. Everything seems settled. But here's the question: how will you apply the annual legal indexation to this evolving rent? Should you take the first stage as the base? The last one? An average?
This question, much more common than one might think, has divided landlords and traders for years. In the Landes region, where commercial activity is dynamic between Mont-de-Marsan and Parentis-en-Born, I have seen many cases where this ambiguity generated costly conflicts. The landlord thought they had negotiated well, the tenant believed they had secured their budget, and in the end, both ended up in court.
The Cour de cassation put an end to this uncertainty in 2013 with a ruling that definitively clarifies the situation. But what exactly does this change for you, as a landlord or tenant? How should you respond to this new legal certainty? Let's delve into this decision that has simplified the lives of thousands of real estate professionals.
The Facts: A Story That Happens Every Day
Mr. Dubois, owner of commercial premises in Parentis-en-Born, had leased his premises to a service company since 2005. The lease was due to expire in 2010. As often happens in this type of negotiation, both parties wanted to secure their future: Mr. Dubois wanted a progressive increase in his rental income, while the tenant company wanted to control its costs over the term.
They therefore agreed on a renewal with rent set in stages (a clause increasingly common in commercial leases). Specifically, the rent would be €1,500 per month for the first three years, then increase to €1,650 for the next three years, and finally to €1,800 for the last three years. Everything seemed perfectly clear on paper.
But this is where things got complicated. Article L. 145-34 of the French Commercial Code provides that the rent of a commercial lease can be revised each year based on a reference index (generally the ICC, the Construction Cost Index). To apply this revision, a base rent is needed to calculate the variation. However, in their agreement, Mr. Dubois and his tenant had not specified which rent would serve as the base for this indexation.
When Mr. Dubois wanted to apply the first annual revision, he took the rent from the first stage (€1,500) as the base. His tenant contested this, considering the method unfair since the rent was already increasing in stages. The conflict escalated, exchanges became acrimonious, and eventually, the matter ended up in court. After an initial judgment unfavourable to Mr. Dubois, he appealed, then lodged an appeal with the Cour de cassation. This is where the highest French judicial court ruled.
The Court's Reasoning — Analysed
The Cour de cassation examined this case with great rigour. The judges recalled the legal basis: Article L. 145-33 of the Commercial Code (which lists the elements to consider when setting the rent of a renewed commercial lease) and especially Article L. 145-34 of the same code (which provides for the annual revision of rent based on indices).
The judges' reasoning is remarkably clear. They first noted that setting rent in stages is perfectly legal and does not contravene any provision of the Commercial Code. In short, landlords and tenants are free to agree on a gradual progression of rent over the lease term.
But beware: this contractual freedom cannot obstruct the application of the mandatory rules of legal indexation. In other words, even with stages, you must be able to determine a base rent to calculate the annual variation. The Court was very firm on this point: “the setting of the price of the lease to be renewed in stages does not exclude the determination of a base rent allowing the application of the index variation”.
In this case, the judges specified that this base rent must be the rent payable during the first three-year period of the lease. For Mr. Dubois and his tenant, this meant that the calculation base would indeed be the €1,500 from the first stage. The annual indexation would apply to this amount, and the staged increases would be added to this already revised rent.
What few people know is that this decision represents an important confirmation of prior case law. It does not radically innovate, but it definitively clarifies a question that was debated. The tenant's arguments (who believed that the stages made indexation inapplicable or should be taken into account) were rejected in the name of legal certainty and the strict application of the texts.
What This Changes for You — Concretely
If you are a landlord in Mont-de-Marsan or elsewhere in the Landes region, this decision provides considerable security. Take a concrete example: you lease a 100m² premises on Rue Victor-Hugo in Mont-de-Marsan for €1,200 per month with stages at €1,350 then €1,500 over nine years. You now know with certainty that your base rent for indexation is €1,200. If the ICC increases by 2% in the first year, your rent becomes €1,224, then will adjust according to the agreed stages.
For tenant traders, the situation is also clarified. You can precisely anticipate your rental costs over the entire lease term. No more unpleasant surprises: you know that indexation will apply to the first stage, and you can integrate this data into your business plan. undefined, I have encountered cases where restaurateurs or traders in Parentis-en-Born had underestimated this double increase (stage + indexation) and found themselves in financial difficulty.
Purchasers of commercial premises must also be vigilant. When you buy a property with an existing lease, check how the current rent has been calculated. Are there stages provided? Is the base rent for indexation clearly identified? These elements directly impact the value of your investment and your future income.
Finally, for co-owners who lease commercial premises in their building, this decision simplifies management. You can establish predictable leases, without fearing subsequent disputes over the calculation method. But how should you react if your current lease does not specify this base rent?
Four Tips to Avoid This Type of Dispute
- Draft an explicit clause in the lease: State in black and white what the “base rent” is for applying annual indexation. Specify that it is the rent applicable during the first three-year period, in accordance with case law.
- Have your lease checked by a professional: Before signing a renewal with stages, consult a specialised lawyer or notary. One hour of advice can save you years of litigation.
- Calculate the amounts over the entire term: Establish a forecast table showing the evolution of rent year by year, integrating both the stages and legal indexation. Share it with the other party for total transparency.
- Negotiate the reference index: If the ICC (Construction Cost Index) increases too sharply for your liking, you can agree on another index (such as the ILC, Commercial Rent Index) within the limits allowed by law.
Besoin d'un conseil personnalisé ? Contactez Maître Zakine — première consultation 30 min à 45€.
In-Depth Analysis: Related Case Law and Developments
This 2013 decision fits into a coherent line of case law. Already in 2005, the Cour de cassation had recalled in ruling No. 03-10.900 that indexation was a mandatory right that could not be set aside by the parties' will. But it is indeed the 2013 ruling that specified its concrete application to leases with stages.
Since then, the courts have regularly applied this principle. For example, in 2018, the Tribunal de grande instance of Dax judged a similar case concerning a commercial lease in Hossegor, firmly reiterating the obligation to determine a base rent distinct from the stages. The trend is clear: judges protect the legal indexation mechanism against any attempt to circumvent it, even through contractual arrangements that appear equitable.
For the future, this stable case law offers great security to market players. It allows landlords and tenants to negotiate while perfectly knowing the rules of the game. However, one can expect new questions to arise, particularly regarding the interaction between these stages and other revision mechanisms (such as the three-year revision provided for in Article L. 145-38).
In Practice: What to Do
FAQ — Your Questions, Our Answers:
1. My current lease provides for stages but no base rent for indexation. What should I do?
You must regularise the situation through a lease addendum. Propose to the other party to specify that the base rent is that of the first stage. If they refuse, consult a lawyer to initiate mediation or legal action.
2. I am a tenant and my landlord applies indexation to the last stage. Is this normal?
No, this is contrary to case law. The base rent must be that of the first stage. You can contest this practice by registered letter, then if necessary through legal action.
3. Can we agree that indexation will not apply at all?
No, legal indexation is of public policy. Any clause derogating from it would be void. You can only choose a different index among those authorised by law.
4. Must the stages necessarily be three-year?
No, the law does not impose a specific duration for stages. They can be annual, biennial, or follow any other rhythm agreed between the parties. Only the base rent for indexation must correspond to the first period.
5. How to concretely calculate my rent with stages and indexation?
Take the amount of the first stage. Apply the indexation coefficient each year (new index / old index). At the stage change, take the new agreed amount, but continue to apply indexation based on the initial base.
Do you find yourself in a similar situation? A first 30-minute consultation with Maître Zakine (€45) can save you months of litigation — and often much more. Book an appointment →

