Irremediable
Non-compliance with the mémoire requirement gives rise to an inadmissibility that cannot be cured after the court has been seised (Cass. 3e civ. 8-2-2024 n° 22-22.301). Even a remission from another court following an incompetence ruling does not waive the requirement — a fresh mémoire must be served.
1 month
The juge des loyers cannot be seised before the expiry of one month following receipt of the first mémoire by its addressee (Art. R 145-27 al. 1). A summons issued before expiry of this period is inadmissible. The period runs from actual receipt — not from dispatch.
Judgment = lease
If neither party withdraws within one month of a final rent-fixing judgment and no draft lease is sent, the judgment itself constitutes the renewed lease (Art. L 145-57 al. 2 C. com.). A judicial decision can create the contractual instrument — one of the most distinctive features of the French commercial lease statute.

When the Mémoire Préalable Is Required

The mémoire préalable is a mandatory preliminary step for any party who takes the initiative of referring a rent dispute to the juge des loyers commerciaux. It must be served before any court application in three situations:

  • Following a tenant's renewal request, to initiate proceedings for the fixing of the renewed lease rent
  • Following a landlord's congé with offer of renewal, for the same purpose
  • Following a request for triennial legal revision of the rent (Cass. 3e civ. 26-1-2017 n° 16-10.304)

The mémoire is required whenever a party takes action to resolve a disagreement on the rent following the pre-litigation phase (Cass. 3e civ. 10-6-1971 n° 70-12.678). Legal representation by a lawyer (ministère d'avocat) is mandatory for all proceedings commenced since 1 January 2020 (C. com. Art. R 145-29).

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The Mémoire Is Not the Renewal Request

The preliminary mémoire is a separate procedural act from the initial renewal or revision demand. A landlord's recorded-delivery letter containing their rent revision request does not constitute a valid mémoire: the law requires a distinct act with specific content and different legal effects (Cass. 3e civ. 19-12-2000 n° 98-16.180 ; Cass. 3e civ. 15-11-2006 n° 05-18.259). Confusing the two will make any resulting court proceedings inadmissible.

Mandatory Content of the Mémoire

The preliminary mémoire must contain two categories of information prescribed by Articles R 145-24 and R 145-25 of the Commercial Code.

Identity Information (Art. R 145-24) — mandatory on pain of formal irregularity
  • For individuals: name, forenames, occupation, domicile, nationality, date and place of birth
  • For legal persons: corporate name and registered office, title, name and forename of legal representative
  • Address of the leased premises
Substantive Content (Art. R 145-25) — mandatory
  • A copy of the renewal or revision request that gives rise to the proceedings
  • Statement of all other claims
  • Legal and factual arguments supporting the party's position or refuting those of the other side
  • Reply briefs or briefs filed after an expert report may contain only legal or factual explanations (Art. R 145-25 al. 5)
  • Copies of all attached documents must be certified as conforming to the original by the signatory (Art. R 145-26)

The preliminary mémoire must be signed by the parties' lawyers (C. com. Art. R 145-26). An unsigned mémoire is affected by a formal irregularity, though one which must cause actual prejudice before it can result in nullity. Notably, an unsigned mémoire can still interrupt prescription even where its nullity is subsequently raised (Cass. 3e civ. 13-2-2002 n° 00-18.671).

Service: Form, Addressee, and Proof

The preliminary mémoire must be served by lettre recommandée avec accusé de réception (recorded delivery) (C. com. Art. R 145-26). Service by acte extrajudiciaire (bailiff service) is equally valid (Cass. 3e civ. 16-10-2013 n° 12-19.352). The party serving the mémoire need only prove that it was presented at the addressee's domicile — actual receipt is not required. It is sufficient that the addressee had the opportunity to collect the item from the postal service following two delivery notices (Cass. 3e civ. 6-11-1986 n° 84-10.103). Where a domicile election has been made at a firm of lawyers, the mémoire must be served on the lawyer directly by recorded delivery.

Individual Service on Every Party: A Trap for the Unwary

Where there are multiple landlords or multiple tenants, a separate mémoire must be served on each one individually. A single mémoire addressed collectively to all co-owners or co-tenants is insufficient (Cass. 3e civ. 3-7-2013 n° 12-13.780). Separate service on each member of the indivision is required even where one holds the entirety in usufruct (CA Versailles 3-2-2005). Service on a deceased person or someone who is no longer the lease holder does not constitute valid service on the actual counterparty (Cass. 3e civ. 18-11-1998 n° 96-22.696). The burden of proving that the mémoire was duly served lies entirely on the party relying on it: a landlord who could not produce proof of delivery to the tenant was held to have issued an invalid summons, and since the two-year prescription had run, the action was inadmissible (CA Paris 21-3-2007 n° 05-11409).

Sanctions for Non-Compliance

Non-compliance with the mémoire requirement gives rise to an inadmissibility (fin de non-recevoir) that is irremediable: it cannot be cured after the court has been seised (Cass. 3e civ. 8-2-2024 n° 22-22.301). This applies even where parties have been remitted to the juge des loyers following a ruling of incompetence by another court: they must still serve a fresh mémoire before filing, and failure extinguishes the proceedings (Cass. 3e civ. 14-9-2011 n° 10-10.037). A party whose first-instance proceedings were declared inadmissible for want of a mémoire loses all right to raise substantive arguments on appeal — including a request for judicial expert appointment (Cass. 3e civ. 13-12-2006 n° 05-20.281).

Irregularities divide into substantive (Art. 117 CPC — lack of standing, lack of authority, incapacity: void regardless of prejudice) and formal (wrong address, missing signature, failure to attach the prior demand: void only if they cause actual prejudice to the adverse party) (Cass. 3e civ. 4-10-1972 n° 71-12.253).

The One-Month Waiting Period and Seising the Court

The juge des loyers cannot be seised before the expiry of one month following receipt of the first mémoire by its addressee (C. com. Art. R 145-27 al. 1). Any summons issued before expiry of this period is inadmissible. The period runs from actual receipt by the addressee — not from the date of dispatch.

After the one-month period, the most diligent party remits their mémoire to the court registry to obtain a hearing date. All mémoires exchanged between the parties and evidence of their service must be included. This lodgement at the registry does not itself seise the juge des loyers and therefore does not interrupt the two-year prescription (Cass. 3e civ. 23-1-2013 n° 11-20.313).

Documents Required at the Registry
  • All mémoires exchanged, with proof of service (acknowledgements of receipt)
  • The lease and all avenants; floor plans of the premises
  • For triennial revision: the revision demand with acknowledgement of receipt, and the last revision document
  • For renewal proceedings: the congé or renewal request, and any conciliation commission opinion

The court is seised by a summons (assignation) issued under the urgent fixed-date procedure (Arts. 840 to 844 CPC). The summons need not reproduce elements already known to the other party (C. com. Art. R 145-28). Legal representation by a lawyer is mandatory (Art. R 145-29).

The Hearing and the Judge's Powers

The procedure before the juge des loyers is a written procedure. At the hearing, parties and their lawyers may only develop orally the arguments already contained in their mémoires (C. com. Art. R 145-29). However, parties may modify their written submissions to raise new arguments during proceedings, even arguments not raised in the original congé or preliminary mémoire (Cass. 3e civ. 30-11-1982 ; Cass. 3e civ. 10-11-2010 n° 09-16.783). In fixing the rent, the judge is bound by the parties' claims: the judicially fixed price cannot exceed the landlord's request or fall below the tenant's (C. com. Art. L 145-37). The tenant must continue paying rent at the previous rate, or at any provisional rate fixed by the judge, pending judgment (C. com. Art. L 145-57 al. 1).

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Privately Commissioned Expert Reports

Expert reports prepared privately at the request of one party (expertises amiables) may be submitted as evidence and courts have accepted them when submitted to the other side's observations (Cass. 3e civ. 23-3-2005 n° 04-11.455). However, the judge cannot decide the case solely on the basis of such a report, even if both parties commented on it: relying exclusively on a unilateral expert report violates the right to a fair trial under ECHR Art. 6 §1 (Cass. 3e civ. 3-2-2010 n° 09-10.631).

When the Judge Appoints an Expert

The juge des loyers may appoint an expert where the parties' positions diverge on factual points that cannot be resolved without expert analysis (C. com. Art. R 145-30 al. 3). The expert's mission covers all standard rental value factors under Articles R 145-3 to R 145-7 and L 145-34, unless the judge limits the mission to specific elements (Art. R 145-30 al. 4).

Post-Report Mémoires: A Second Mandatory Step

Once the expert has filed their report, the parties must exchange new mémoires en ouverture de rapport before the resumed hearing date. This is a substantive mandatory formality whose omission vitiates the entire procedure — even where a party has nothing new to add (Cass. 3e civ. 24-6-1998 n° 96-19.730 ; Cass. 3e civ. 30-4-2003 n° 525). Filing court submissions (conclusions) instead of a mémoire after the expert report is not sufficient: conclusions are not a mémoire and the procedural nullity permanently extinguishes the rent-fixing proceedings (Cass. 3e civ. 30-4-2003 n° 525 ; Cass. 3e civ. 4-2-2009 n° 08-10.723 ; Cass. 3e civ. 22-11-2011 n° 10-25.686). A new summons issued after the expert report instead of a post-report mémoire is equally affected by substantive nullity (Cass. 3e civ. 13-10-2010 n° 09-66.600).

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The Regularisation Window

The Cour de cassation has attenuated the harshness of the post-report mémoire rule: a procedural irregularity arising from its absence can be cured by the subsequent service of a valid mémoire, provided two conditions are met: the regularisation must occur within the two-year prescription period, and the court must not yet have ruled (Cass. 3e civ. 17-9-2008 n° 07-16.973 ; Cass. 3e civ. 22-1-2013 n° 11-28.184). Where the two-year prescription has already expired or the court has ruled, regularisation is no longer possible.

The Judgment and Its Effects

The judgment of the juge des loyers fixing the rent is provisionally enforceable as of right for all proceedings commenced since 1 January 2020 (CPC Art. 514; Décret 2019-1333 of 11-12-2019). The rent-fixing judgment cannot carry a condemnation: the juge des loyers may fix the rent and settle the resulting account but may not issue a payment order (Cass. 3e civ. 11-5-2022 n° 20-21.689 ; Cass. 3e civ. 18-3-1992 n° 497). The five-point surcharge on the statutory interest rate that applies to payment condemnations therefore does not apply to a rent-fixing judgment.

Where the judgment has become final and neither party has exercised the right to withdraw within one month, and the landlord has not sent a draft lease conforming to the decision for signature, the judgment itself constitutes the renewed lease (C. com. Art. L 145-57 al. 2). For interest on rent arrears: where the landlord initiated proceedings, interest on the rent differential runs from the date the summons was issued; where the tenant took the initiative, interest runs from the date of the landlord's first response mémoire (Cass. 3e civ. 18-6-2014 n° 13-14.715).

The Full Mémoire Procedure at a Glance
1
Serve the Preliminary Mémoire
Signed by lawyer. By LRAR or extrajudicial act. Individually on each party. Contains identity, copy of the prior demand, all claims, and supporting arguments (Art. R 145-24 and R 145-25).
2
Wait One Month
The court cannot be seised before one month from receipt by the addressee (Art. R 145-27 al. 1). Use this period to negotiate. Any summons before expiry is inadmissible.
3
Lodge at the Registry and Issue Summons
Lodge all mémoires and documents at the registry to obtain a hearing date. Issue the assignation under the urgent fixed-date procedure (Arts. 840–844 CPC). Lodging at registry alone does not interrupt prescription.
4
Hearing and Expert Appointment (if ordered)
Written procedure; oral arguments limited to what is in the mémoires. Judge may appoint an expert. If so, post-report mémoires are mandatory — filing conclusions instead permanently extinguishes proceedings.
5
Judgment and Follow-Up
Provisionally enforceable as of right (proceedings since 2020). No condemnation possible. If final and no withdrawal within one month and no draft lease sent: the judgment itself constitutes the renewed lease (Art. L 145-57 al. 2).
The Mémoire Préalable Procedure: The Essentials
Required in three situations: tenant's renewal request, landlord's congé with offer of renewal, and triennial revision request. It is a separate act from the initial renewal/revision demand — sending the demand does not serve as the mémoire (Cass. 3e civ. 15-11-2006).
Must be signed by the parties' lawyers; mandatory representation since 1 January 2020. Must contain: identity details, copy of the prior demand, all claims, and supporting arguments. All attached documents must be certified as conforming.
Service by recorded delivery (LRAR) or extrajudicial act; service at the addressee's domicile suffices even without actual receipt. Separate service required on each individual co-owner or co-tenant — collective service is insufficient (Cass. 3e civ. 3-7-2013).
Failure to serve the mémoire = irremediable inadmissibility of the court proceedings (Cass. 3e civ. 8-2-2024). Even a remission from another court does not waive the requirement. The court cannot be seised before one month has elapsed from the addressee's receipt (Art. R 145-27).
Lodging at the registry to obtain a hearing date does not seise the court and does not interrupt prescription (Cass. 3e civ. 23-1-2013). The judge is bound by the parties' positions: the judicial rent cannot exceed the landlord's demand or fall below the tenant's (Art. L 145-37).
After an expert report, new post-report mémoires are mandatory — even if nothing new is added. Filing conclusions instead permanently extinguishes the proceedings (Cass. 3e civ. 30-4-2003 ; Cass. 3e civ. 4-2-2009). Regularisation is possible if done within the 2-year prescription period and before the court has ruled (Cass. 3e civ. 17-9-2008).
Judgments are provisionally enforceable as of right for proceedings since 1 January 2020. The judgment cannot contain a condemnation (Cass. 3e civ. 11-5-2022). If final with no withdrawal within one month and no draft lease sent, the judgment itself constitutes the renewed lease (Art. L 145-57 al. 2).
Navigating a French Commercial Lease Rent Dispute?

The mémoire préalable procedure is technically demanding — one wrong step can permanently extinguish your right to have the rent fixed. The irremediable inadmissibility rules and the post-report mémoire trap require precise procedural handling at every stage.

Speak with a French Lawyer

This article is for general information and educational purposes only. It does not constitute legal advice. Laws may have changed since publication. Always seek qualified French legal advice before taking steps in commercial lease rent proceedings.