End of the Employment Contract

Collective Redundancies and Social Plan in Luxembourg

When an employer plans to cut several positions for economic, organisational or technological reasons, Luxembourg law requires a strictly regulated procedure before a single individual dismissal notice may be served. This procedure rests on three pillars: prior notification to the authorities (ADEM and ITM), negotiation of a social plan with employee representatives, and observance of a seventy-five-day effective period. Any dismissal notified without following these steps is struck with absolute nullity.

Legal basis: Art. L.166-1 to L.166-9 Labour Code Updated: June 2026

1. Definition and triggering thresholds

A redundancy is qualified as collective when it concerns reasons not inherent to the individual employees — economic reasons, restructuring, post elimination — and the number of planned terminations reaches one of the two following thresholds (Art. L.166-1):

Reference period Minimum number of redundancies
30 consecutive daysAt least 7 employees
90 consecutive daysAt least 15 employees

Also treated as redundancies are employer-initiated contract terminations for non-personal reasons — mutual agreement terminations under economic pressure, non-renewal of a fixed-term contract for economic reasons — provided that the redundancies in the strict sense number at least four (Art. L.166-1). This assimilation rule is designed to prevent employers from circumventing the thresholds by using alternative forms of termination.

The thresholds are assessed on a rolling 30- or 90-day window. An employer who makes six employees redundant in January and two in February may therefore cross the threshold of seven over the 30-day window spanning late January and early February, and find themselves subject to the procedure retrospectively — which is why anticipation from the very first planned dismissal is essential.

2. Mandatory notification to ADEM and information of employee representatives

Once the thresholds are reached, the employer must notify any collective redundancy project in writing to ADEM (the Employment Development Agency), which forwards a copy to the ITM (Labour and Mines Inspectorate). This notification must be made no later than the start of the negotiations with employee representatives — it cannot therefore be deferred until a potential agreement is concluded (Art. L.166-4).

Simultaneously, the employer sends to the employee representatives — staff delegates and, where applicable, trade union organisations party to the applicable collective agreement — a detailed written communication which must include (Art. L.166-3):

The grounds for the project: the economic, organisational or technological nature of the planned restructuring. The number and categories of employees affected, together with the usual number of employees. The envisaged period for implementing the redundancies. The selection criteria for the employees who will actually be made redundant, in the order of priority adopted by the employer. Finally, the method for calculating any indemnities exceeding the statutory or contractual minima.

An incomplete notification — omitting, for example, the selection criteria or the method for calculating indemnities — exposes the employer to challenges to the regularity of the procedure. Employee representatives may demand additional information before entering into negotiations.

Insolvency

Where a court decision declares the employer insolvent, the initial notification to ADEM is only required if the competent authority — in practice the commercial court or the receiver — expressly requests it (Art. L.166-4). This exception reflects the urgency inherent in insolvency proceedings, which makes it impossible to observe the ordinary procedural deadlines.

3. Negotiations and content of the social plan

From the date of notification, the employer is required to open good-faith negotiations with employee representatives with a view to concluding a social plan. These negotiations have a content imposed by law: they must compulsorily cover, first and before any discussion of how the redundancies will be carried out, two areas (Art. L.166-2):

Avoiding or reducing the number of redundancies: working-time reduction measures, short-time working, recruitment freezes, internal transfers, voluntary departure incentives, early retirement. The employer cannot present the redundancies as a fait accompli from the outset of the negotiations.

Mitigating the consequences of unavoidable redundancies: social support measures (above-statutory indemnities), internal or external redeployment actions, retraining programmes, outplacement cells, transitional short-time working, maintenance of certain benefits during the transition period.

Once negotiated, the social plan takes the form of an agreement signed by the employer and the employee representatives. It crystallises the commitments of both parties and constitutes an enforceable instrument in the event of subsequent default by the employer.

4. Outcome of negotiations: agreement or referral to the ONC

The law imposes a precise timetable for the outcome of the negotiations, depending on whether or not they result in an agreement (Art. L.166-2).

Where agreement is reached

The parties sign the social plan no later than fifteen days after the start of the negotiations. A copy is sent without delay to ADEM and the ITM. This fifteen-day period is a maximum: the parties may conclude sooner if they reach an earlier agreement. The social plan is then binding on all affected employees, including those who are not members of the signatory delegation.

Where agreement is not reached

If the negotiations fail, the parties sign minutes of disagreement formally recording the failure of the negotiations and its reasons. These minutes are sent to ADEM and the ITM.

The parties must then jointly refer the matter to the National Conciliation Office (ONC) no later than three days after the minutes of disagreement are signed. This deadline is mandatory: failure to comply results in foreclosure, meaning the permanent loss of the right to approach the ONC. The ONC attempts to mediate between the parties in order to reach a conciliation agreement that serves as a social plan (Art. L.166-2).

The three-day deadline for referring the matter to the ONC is particularly short. The employer and employee representatives must coordinate immediately after signing the minutes of disagreement to file the joint referral. A unilateral referral — by the employer alone or by the representatives alone — is not valid.

5. Individual dismissal notices and effective period

The employer may only serve individual dismissal notices after one of the two following conditions has been met (Art. L.166-5):

The signing of the social plan, whether resulting from a direct agreement between the parties or from a conciliation obtained before the ONC. Or the signing of the ONC's minutes recording the failure of conciliation, if the parties were unable to reach an agreement even with the assistance of the mediator.

Any individual dismissal notice for a non-personal reason or summons to a pre-dismissal interview served before the social plan or the ONC minutes are signed is void and of no effect (Art. L.166-2). This nullity is absolute: it cannot be remedied either by a subsequent agreement between the parties or by the payment of compensation.

Effective period for collective redundancies

Once individual notices have been duly served, collective redundancies take effect only at the expiry of a period of seventy-five days from the individual notice, without prejudice to any longer ordinary notice periods provided by law or the applicable collective agreement (Art. L.166-6).

This seventy-five-day period may be adjusted by the Minister responsible for Labour: it may be extended to ninety days to allow redeployment measures to be implemented, or reduced to the length of the ordinary notice period if the support measures are already operational.

6. Penalties and the controlling company

Nullity and right to reinstatement

Where the procedure has not been observed, each dismissed employee may apply to the president of the labour court sitting in urgent proceedings to have their dismissal declared void and overturned. This action must be brought within fifteen days of notification of the individual dismissal (Art. L.166-2). If successful, the judge may order the employee's reinstatement in the business.

Damages for wrongful termination

Independently of the nullity action, employees affected by a collective redundancy that does not comply with the provisions of Articles L.166-2 to L.166-6 are entitled, in addition to their statutory redundancy indemnities, to damages for wrongful termination of contract (Art. L.166-9). These damages are distinct from those provided for in cases of individual unfair dismissal and may be combined with them.

Decision emanating from a controlling company

The fact that the redundancy decision was not taken by the employer itself but by a parent company or controlling entity — within an international group, for example — does not relieve the employer of its procedural obligations. The entire social plan procedure must be observed, even if the restructuring decision was taken at group level without prior consultation of the local entities (Art. L.166-8). The employer cannot hide behind group instructions to justify non-compliance with the deadlines or the absence of negotiations.

In practice, the responsibility for observing the procedure always falls on the employing legal entity, regardless of the group's capital structure. Local managers must therefore anticipate group restructuring decisions and allow sufficient time for the Luxembourg procedure to be carried out.

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The information in this guide is provided for informational purposes only and does not constitute legal advice. It may contain inaccuracies or may not reflect the latest legislative or case-law developments. For any specific situation, please consult a qualified legal professional.