Luxembourg employment contracts (CDI / CDD)

CDI vs CDD

The Code du Travail makes the contrat à durée indéterminée (CDI) the default form of employment contract — open-ended, terminable on notice and on stated grounds. The contrat à durée déterminée (CDD) is the exception. It is allowed only on grounds set out in Articles L.122-1 et seq.: replacement of an absent employee, seasonal work, an exceptional and temporary increase in activity, a specific time-limited project, or certain categories laid down by Grand-Ducal regulation. A CDD that does not fit one of these grounds is reclassifiable as a CDI by a labour court — and the reclassification is retroactive to the original start date.

CDDs have capped duration (cumulative across renewals) and capped number of renewals; both ceilings are set in the Code du Travail. The contract must be in writing, must state its grounds and its end date or terminating event, and must include the standard contract elements (job description, salary, working time, place of work). Verbal CDDs do not exist legally; the absence of a written contract converts the relationship into a CDI.

A separate category exists for temporary agency work (travail intérimaire), in which the employer is an agency that hires the worker on a CDD and posts them to a user company under a mission contract. The user company does not become the employer; the agency does. The rules on grounds, duration and renewals follow the CDD framework but with specifics on the mission contract.

For an arriving candidate, the practical heuristic is to ask for a CDI whenever the role is structural — anything other than a clear replacement, project or seasonal need. CDIs are not harder to negotiate in Luxembourg than CDDs in most established sectors; they simply require an employer willing to commit. Where the employer insists on a CDD, the offer letter should state the precise legal ground.

Trial period rules

The trial period (période d'essai) is a separate clause that can be added to either a CDI or a CDD. The Code du Travail caps its maximum duration by tenure tier, reflecting the qualification expected of the role. Lower-tier roles have a shorter maximum (measured in weeks); higher-qualified salaried roles can extend further (measured in months); senior management contracts can go further still. The exact maxima are in the Code; the contract can shorten them but cannot exceed them, and a clause beyond the cap is reduced by law to the maximum permitted.

Two structural points to remember. First, the trial period must be set out in writing in the original contract; it cannot be introduced verbally or by an annex signed after the start. Second, during the trial period, both sides can terminate the relationship with a shorter notice than under a confirmed contract — but the notice still exists, it is not zero. The shorter notice does not apply during the first two weeks of trial, which is the only window in which immediate termination is permitted.

Practical consequence: if the contract is silent on a trial period, there is no trial period. If the contract states a trial period beyond the statutory cap, only the capped portion is enforceable; the excess is void. And if an employee or employer wishes to terminate during trial, the shorter notice still requires a written notification respecting its delay.

Notice periods

Notice periods are structured in two dimensions: by seniority and by who initiates the termination. The employer-owed notice rises stepwise with the employee's continuous service — short for less than five years, longer between five and ten, longer still beyond ten. The employee-owed notice, when resigning, is generally half the employer-owed notice at the same tenure. The Code du Travail sets the table; collective bargaining agreements (conventions collectives) can extend the employer-owed notice but cannot shorten it; the contract can grant longer notice to the employee but cannot reduce the statutory minimum.

The notice period runs from a specific calendar reference point set in the Code — the 1st or the 15th of the month following the notification, depending on the date of notification. This produces shorter or longer effective notice than the nominal length, depending on when the letter is sent. The notification itself must be made by registered letter with acknowledgement of receipt (lettre recommandée avec accusé de réception) or handed over with a counter-signature; informal notice (an email, a verbal statement, a Slack message) does not start the clock.

During notice, the contract continues in force: salary is paid, social security is owed, the employee continues to work unless garden-leave is granted. Both sides retain ordinary obligations of loyalty and confidentiality. Termination at the end of notice is automatic and does not require a separate event.

13th month

The 13th month is one of the most-asked-about elements of a Luxembourg offer — and it is not mandatory. The Code du Travail does not require it; it is created either by the contract, by a collective bargaining agreement covering the sector, or by a recurring company practice (usage) that has become binding. Whether or not a particular role pays a 13th month therefore depends on negotiation and on the sector — it is close to universal in banking, insurance and large corporates, common in EU institutions, less standard in retail, hospitality and small businesses.

Where granted by contract, the 13th month is paid prorated to time worked over the calendar year, with the lump usually disbursed in November or December (some employers spread it equally over twelve months instead). It is taxed as ordinary salary — the retention at source rises that month — and the resulting fiscal asymmetry can be unwelcome, sometimes producing a small tax adjustment via form 100. Where the 13th month is created by a long-standing company usage rather than by the contract, the employer can extinguish it only by formally denouncing the usage in advance and respecting an information delay.

Bonus and variable

The treatment of bonuses depends on the wording. A discretionary bonus ("the employer may, in its sole discretion, grant a bonus") is exactly that — discretionary, and not a right. A contractual bonus ("the employee will receive a bonus of X% of base salary subject to objectives") is a binding entitlement, payable when the conditions are met. The boundary lies in the language: discretionary words at the start of the clause, objective triggers further on, and the courts will scrutinise whether the substance matches the label.

Three clauses to read carefully in any variable plan. First, conditions for receipt — is the employee required to be present on the payment date, or does pro rata apply to leavers? Second, computation — is the bonus computed on base salary or total earnings, and is the percentage capped? Third, governing plan — is the variable defined in the contract directly, or by reference to an annual plan that the employer can modify? An offer that promises a variable component "to be defined annually" gives the employer wide latitude.

Non-compete clauses

Non-compete clauses (clauses de non-concurrence) are valid in Luxembourg but tightly regulated. A clause that does not meet all of the following conditions is unenforceable:

• In writing, in the contract or an annex signed contemporaneously.
• Time-limited — the duration cannot exceed the cap set by case law and the Code (typically twelve months).
• Geographically limited — a Luxembourg-only or regional scope is enforceable; a worldwide non-compete is not.
• Activity-limited — restricted to activities the employee actually performed, not to the entire economic sector.
• Financially compensated — the employee must receive financial compensation for the restriction, typically a monthly indemnity for the duration of the clause.

A non-compete is also unenforceable against an employee who is dismissed without serious cause, and it does not survive a transfer of undertaking unless reaffirmed. In practice, junior roles rarely have enforceable non-competes; senior commercial and technical roles do. Offer letters that include a worldwide, multi-year, unpaid non-compete are not enforceable as written, but signing one creates uncomfortable friction at exit and is best renegotiated before signing.

Termination

Luxembourg termination law has two main procedures, each with its own steps and its own risks.

Regular dismissal (with notice)

The employer terminates the contract for a non-misconduct reason — economic, organisational, performance — by registered letter, respecting the notice period set by seniority. In firms employing more than 15 employees, the employee can request a written statement of the reasons within one month (the motif réel et sérieux), and the employer must provide them within one month. The reason can be challenged before the labour court (tribunal du travail); if found insufficient, the dismissal is unfair (abusive) and gives rise to damages.

Employees with three years' continuous service or more are entitled to severance pay (indemnité de départ), the amount of which scales with tenure. In firms above 15 employees the employer can choose between paying severance or extending notice; in smaller firms, severance is generally substituted by a longer notice. The Code lays out the table precisely.

Gross misconduct (faute grave)

For conduct so serious that the employment relationship cannot reasonably continue, the employer can dismiss without notice and without severance — but only after following a strict procedure. The employer must first convene the employee to a preliminary interview (entretien préalable) at least one working day in advance, in firms employing more than 150 employees; smaller firms have a more abridged process. The dismissal letter must then articulate the precise facts; vague references to "loss of trust" without specifics fail at the labour court. The notification must occur within one month of the employer learning of the facts.

Large redundancies

Above defined thresholds (typically 7 dismissals over 30 days or 15 over 90 days), the employer must initiate a plan de maintien dans l'emploi or a plan social, with negotiation with staff representatives and notification to the ITM and the Comité de conjoncture. The ITM scrutinises these plans carefully, and the courts are not deferential to a thinly justified one.

Regular vs. faute grave termination — quick comparison

Element	Regular dismissal	Faute grave
Notice	Yes (by seniority)	No
Severance	Yes (≥3 years tenure)	No
Motif requirement	Réel et sérieux (firms >15)	Conduct making continuation impossible
Procedure	Registered letter; statement of reasons on request	Preliminary interview (firms >150); time-limited notification
Risk if challenged	Dismissal found abusive → damages	Faute downgraded → notice + severance owed; possibly abusive damages

Edge cases

Senior management contracts

Certain senior roles fall partially outside ordinary working-time rules (notably daily/weekly hours). Designation as a cadre supérieur requires a specific salary level and real decision-making autonomy, both interpreted strictly by the courts. A "cadre supérieur" label without substance does not deprive the employee of the standard protections.

Expatriate clauses

For internationally mobile employees, clauses on tax equalisation, repatriation, the impatriate regime under Luxembourg's expatriate tax provisions, and currency-of-payment merit careful drafting. The clause should specify which costs (housing, schooling, removal, tax assistance) the employer bears and for how long.

Secondments

An employee seconded into Luxembourg from a foreign parent remains contractually with the parent, but a Luxembourg co-employment relationship can be inferred where supervision and integration are sufficient. Posted-worker rules under EU Directive 96/71 apply for short-term EU postings.

Remote work clauses

Hybrid and remote arrangements increasingly carry their own clauses — location of work, equipment provision, expense reimbursement, and the count of days physically worked outside Luxembourg, which can affect both labour-law jurisdiction and the tax/social-security treatment under the bilateral conventions covered in the cross-border pillar.

What this means in practice

1. Read the contract against the Code, not on its own. The Code is the floor: any clause worsening notice, trial period, non-compete compensation or termination procedure is void. The mental model is "what does the Code grant me, and does the contract take any of it away?"
2. Negotiate before signing. Non-compete duration, geography and compensation, the structure of the variable bonus, the 13th month, the trial period: all of these are negotiable. Once signed, modifying them requires the employer's agreement.
3. Get specialist advice before resigning or contesting a dismissal. Labour-law deadlines are tight (one month to request a statement of reasons, three months to bring an unfair-dismissal claim). The Chambre des salariés offers free first-line advice; specialist labour-law firms handle the contested cases.

Frequently asked

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