CDI vs CDD: Legal and Practical Differences

Hiring an employee involves a contractual choice with major legal, financial and organizational consequences: the open-ended contract (CDI) or the fixed-term contract (CDD). These two forms of employment are governed by the French Labor Code, but operate according to radically different logics. The CDI constitutes the norm, the CDD the legal exception. Understanding their respective regimes makes it possible to avoid costly reclassifications, labor court disputes and procedural errors when signing. This article guides you through the essential distinctions between CDI and CDD, their conditions of validity, their modes of termination and best practices for formalizing them, particularly via electronic signature for HR.

The legal foundations of CDI and CDD

CDI: common law contract

The open-ended contract (CDI) is the normal and general form of employment relationship in France, as established by article L.1221-2 of the Labor Code. It does not contain a deadline set in advance: it binds the employer and the employee until the occurrence of a cause of termination (resignation, dismissal, conventional termination, retirement, force majeure, etc.).

The CDI can be concluded without writing for full-time relationships, but practice — and often collective agreements — systematically impose a written document signed by both parties. No minimum duration is required, but termination must comply with strict procedures, particularly when it comes from the employer.

The part-time CDI, however, must necessarily be established in writing (art. L.3123-6 of the Labor Code) and mention the weekly or monthly duration, the distribution of working hours, the conditions of any modification, and the guarantees granted to the employee.

CDD: contract of exception subject to conditions

The fixed-term contract is governed mainly by articles L.1242-1 to L.1248-11 of the Labor Code. Its fundamental peculiarity: it can only be concluded for the performance of a specific and temporary task. The law defines restrictively the authorized cases of use:

• Replacement of an absent employee (illness, maternity leave, etc.)

• Temporary increase in activity

• Seasonal employment

• Contracts of usage in certain sectors (hospitality, audiovisual, education, etc.)

• Contracts concluded within the framework of employment policies (subsidized contracts)

A CDD concluded outside these legal reasons is presumed to be a CDI, which exposes the employer to automatic reclassification by the Labor Court.

Mandatory provisions: CDI and CDD under scrutiny

The CDD must necessarily be drafted in writing and delivered to the employee within two business days following hiring (art. L.1242-12). Failing this, it is deemed to have been concluded for an indefinite duration. It must include:

• The precise definition of the reason for use

• The deadline or minimum duration

• The job description

• Remuneration (identical to an equivalent CDI)

• The applicable collective agreement

• The duration of any trial period

The CDI, when written (which is quasi-systematic in practice), must specify the position, remuneration, place of work, working hours and, where applicable, the trial period. The use of an AI contract generator can help structure these documents in compliance with current legal requirements.

Duration, renewal and deadline: the key rules

Maximum duration of CDD

The total duration of a CDD, including renewals, cannot exceed 18 months in most cases (art. L.1243-13). Exceptions exist:

• 9 months in case of exceptional export orders or urgent safety work

• 24 months for contracts executed abroad or when the employee leaves before the deadline within the framework of permanent hiring

Renewal is possible a maximum of twice, provided that the total duration remains within legal limits and that the conditions for renewal are provided for in the initial contract or are the subject of an amendment signed before the deadline.

The waiting period between two CDDs

An employer cannot conclude a new CDD for the same position without a waiting period equal to one-third of the duration of the previous contract (if the latter is less than or equal to 14 days) or half (if greater than 14 days). This period is intended to prevent the abusive recourse to successive CDDs as a disguised substitute for CDI.

The trial period: a different duration depending on the contract

For a CDI, the duration of the trial period is set by law and collective agreements:

• Workers and employees: 2 months

• Supervisors and technicians: 3 months

• Managers: 4 months

For a CDD, the trial period is one day per week of contract, limited to 2 weeks (contracts ≤ 6 months) or one month (contracts > 6 months).

Remuneration, allowances and termination: distinct regimes

End-of-contract allowance: CDD specificity

At the end of a CDD, the employee receives a precarity allowance equal to 10% of the total gross remuneration received (art. L.1243-8). This allowance can be reduced to 6% if the employer undertakes to provide professional training to the employee, in certain sectors. The CDI does not provide for this allowance at its expiration, except in the case of dismissal (legal or contractual allowance).

Modes of termination

For the CDI:

• Resignation (notice period to be respected)

• Dismissal for personal or economic reasons (strict procedure, notice, allowances)

• Conventional termination approved (art. L.1237-11 to L.1237-16)

• Retirement, invalidity, death

For the CDD: Premature termination is strictly regulated. It is only possible in the following cases:

• Mutual agreement of the parties

• Gross misconduct

• Force majeure

• Unfitness ascertained by the occupational physician

• Hiring on CDI

Any premature termination outside these circumstances exposes the author to damages. If it is the employer who terminates abusively, the employee may obtain at least the salary he would have received until the end of the contract.

Equal pay principle

The principle of equal treatment requires that the remuneration of an employee on CDD be at least equivalent to that received by an employee on CDI occupying the same position with the same qualification and seniority. This rule also applies to conventional benefits, bonuses and salary accessories.

Formalizing the contract: the challenges of signature and archiving

Why contract signature is a critical step

The signature of the employment contract — CDI or CDD — materializes the agreement of the parties and commits them to precise rights and obligations. In case of dispute, the absence of a signed written contract significantly weakens the employer's position. For the CDD in particular, the absence of signature within legal timeframes results in reclassification as a CDI by operation of law.

Electronic signature in business now represents a compliant and effective solution for formalizing these documents. Recognized by the French Civil Code (art. 1367) and the eIDAS regulation, it has the same legal value as a handwritten signature when it meets the required reliability requirements.

Electronic signature and employment contract: recommended signature level

For an employment contract, whether a CDI or a CDD, advanced electronic signature (AES) is generally recommended. It guarantees the identification of each signatory, the integrity of the document and non-repudiation. The use of qualified electronic signature (QES), the highest level defined by eIDAS, may prove relevant for contracts with high stakes (senior managers, contracts containing significant non-compete clauses).

To deepen your understanding of signature levels and choose the solution adapted to your HR needs, the complete guide to electronic signature is a useful reference. You can also consult the comparison of electronic signature solutions to evaluate the platforms available on the market.

Archiving and probative value

An electronically signed contract must be archived under conditions that guarantee its durability and integrity. ETSI recommendations and best practices in the sector recommend time-stamped archiving, with retention for at least 5 years (limitation period for individual employment relationships, according to art. L.1471-1 of the Labor Code), or even 10 years for certain documentary obligations.

Legal framework applicable to CDI, CDD and their signature

Labor law: founding texts

The legal regime of the CDI and CDD is based mainly on the Labor Code, in particular:

• Art. L.1221-2: principle of CDI as common law contract

• Art. L.1242-1 to L.1242-3: definition and legal reasons for recourse to CDD

• Art. L.1242-12: obligation to provide written documentation and deadline for transmission of CDD

• Art. L.1243-8: precarity allowance due at the end of the CDD

• Art. L.1243-13: maximum duration of the CDD

• Art. L.1237-11 to L.1237-16: conventional termination of CDI

• Art. L.1471-1: two-year limitation period for actions relating to the performance or termination of the employment contract

The jurisprudence of the Court of Cassation (social chamber) continuously specifies and supplements these texts. Collective agreements and accords may adapt certain durations or conditions at the margin, without being able to derogate from absolutely mandatory provisions.

Legal value of electronic signature on an employment contract

Electronic signature has been recognized as a valid mode of consent in French law since the ordinance of June 16, 2005 (transposing European Directive 1999/93/EC), now codified in articles 1366 and 1367 of the Civil Code. Art. 1366 states that electronic writing has the same probative force as paper writing insofar as the person from whom it emanates can be properly identified and it is established and preserved under conditions designed to guarantee its integrity.

Art. 1367 specifies that electronic signature consists in the use of a reliable identification process guaranteeing its link with the act to which it is attached.

At European level, the eIDAS Regulation No. 910/2014 (in force since July 1, 2016, updated by eIDAS 2.0 currently being deployed) defines three levels of electronic signature: simple, advanced and qualified. Only qualified signature benefits from an irrefutable presumption of equivalence to handwritten signature (art. 25 of the regulation). Advanced signature, very widespread in HR, offers a level of security and traceability sufficient for the vast majority of employment contracts.

Data protection

The collection and processing of signatory data (name, email address, biometric data if applicable) in the context of electronic signature of an employment contract are subject to GDPR No. 2016/679. The employer must inform the employee of the processing of their data (art. 13 GDPR), specify its purpose (HR management, contractual archiving), the retention period and the rights available to the employee (access, correction, erasure under conditions).

Electronic signature providers must be qualified in accordance with ETSI EN 319 132 standards (XAdES/CAdES/PAdES signature) and, when they operate as processors within the meaning of the GDPR, sign a data processing agreement (DPA) with their clients.

Legal risks in case of non-compliance

• CDD reclassification as CDI: whenever a legal reason is absent, the written document is absent or delivered outside the legal deadline, or the maximum duration is exceeded.

• Nullity of contractual clauses: a non-compete clause without financial consideration, an overly imprecise mobility clause, or an excessive trial period are deemed unwritten.

• Labor court disputes: the limitation periods are 2 years for actions relating to the performance or termination of the contract, and 3 years for actions to recover wages (art. L.3245-1).

Usage scenarios: CDI, CDD and electronic signature in practice

Scenario 1: An industrial SME managing seasonal peaks

An industrial SME with about fifty employees experiences two periods of high activity each year requiring the hiring of about ten temporary or seasonal CDD workers for 4 to 6 months. Before digitizing its HR processes, the HR department transmitted contracts by mail or in person, generating delays often exceeding the two business days imposed by law, and risks of document loss.

By deploying an advanced electronic signature solution, the company reduced the time to formalize the contract from 72 hours to less than 4 hours on average. Contracts are time-stamped, automatically archived and accessible in case of URSSAF or labor inspection audits. The risk of reclassification due to the absence of a written document has been eliminated. Sectoral studies in HR management estimate that the digitization of contracts reduces administrative costs by 40 to 60% compared to paper processes.

Scenario 2: A recruitment firm specializing in senior profiles

A recruitment firm assisting companies in hiring senior managers and executives frequently manages CDIs with complex clauses: non-compete, confidentiality, profit-sharing, telework. Each contract requires multiple iterations between the legal department, HR and the candidate, sometimes located abroad.

Thanks to the adoption of an eIDAS-compliant electronic signature platform, the firm eliminated international postal shipments and reduced the signing cycle from an average of 8 days to 1.5 days. Enhanced signatory identification (via online identity verification) guarantees non-repudiation, essential for contracts with significant financial stakes. The firm was also able to integrate standardized contract templates for recurring clauses, further accelerating initial drafting.

Scenario 3: A group of private clinics managing medical replacements

A group of private clinics with about 600 beds frequently calls on replacement doctors on short-term CDDs (sometimes 48 to 72 hours) to ensure continuity of care during leave or unforeseen absences. Constrained timeframes made paper signature practically impossible: the doctor could begin to exercise before the contract was even formalized, exposing the facility to legal and liability risks.

The integration of a mobile electronic signature workflow — allowing the practitioner to sign from their smartphone in less than five minutes — made it possible to systematize contract formalization before the start of the assignment. The rate of contracts signed before the start of the mission increased from 34% to more than 97% in six months. This enhanced compliance also simplified internal audits and social declarations.

Conclusion

The choice between CDI and CDD is never insignificant: each contract commits specific rights and obligations, governed by a dense legal corpus that HR and legal teams must master perfectly. The CDI, a reference contract, offers stability and flexibility in termination according to established procedures. The CDD, a contract of exception, meets legitimate temporary needs but comes with strict constraints of form, duration and reason.

In both cases, written formalization and contract signature constitute a critical step, now facilitated by eIDAS-compliant electronic signature solutions. Digitalizing this process means reducing timeframes, securing proof and eliminating risks of reclassification due to formal defects.

Certyneo supports HR and legal teams in the digitization of their employment contracts, from onboarding to secure archiving. Discover our offers and pricing or calculate your return on investment to estimate the concrete gains of adopting electronic signature in your organization.