It must be in writing, runs from two weeks to twelve months depending on qualification and pay, and ends on a very short notice: what an employer needs to know before signing.

In short. In Luxembourg, a trial period only exists if it is written into the contract, at the latest on the first day of work. It runs from a minimum of 2 weeks to 6 months in the general case, 3 months for an employee whose training is below the CATP level, and up to 12 months for high earners (gross monthly pay of at least 5,318.41 € since 1 June 2026). During the trial, the contract ends in writing, with no severance, on a short notice that depends on the agreed length. In the first two weeks, neither side can walk away alone, except for gross misconduct. Sickness extends the trial, capped at one month.

The trial period is the clause people draft fastest and read least. That is a shame, because it sets the only window in which you and your new hire can part ways quickly and without having to justify it. Get it wrong and it turns against the employer: one missing clause and the contract is permanent from day one; too long a duration and the excess is void. Here is how the trial period actually works for a Luxembourg SME: its form, its lengths, how to end it and the notice involved, and what it changes on payroll.

What is a trial period in Luxembourg?

The trial period is the opening phase of a contract during which the employer and the employee test each other and can part on lighter rules, with a reduced notice and no severance. It is not mandatory: it applies only if the employment contract provides for it in writing. Once it is over, the contract continues on the normal terms of the permanent (CDI) or fixed-term (CDD) contract.

A trial period must be in writing, or it does not exist

This is what employers underestimate most. The trial period must be set down in writing in the employment contract, or in the applicable collective agreement, no later than the first day of work. Without a written clause within that deadline, there simply is no trial: the contract is deemed permanent from day one, and parting ways then goes through the full dismissal procedure, with its long notice and, where applicable, its severance pay.

The clause must state a precise length. A trial period set beyond the legal maximum is not void in full: it is merely cut back to the authorised ceiling for the excess. In other words, writing "9 months" for an employee who is not entitled to it does not give you 9 months, but 6. And it cannot be renewed: once the agreed length has run out, you do not extend it to buy time to decide. The written contract, from the very first hire, is one of the steps we set out in our guide to hiring your first employee in Luxembourg.

What is the maximum length, by profile?

The minimum is two weeks in every case. The maximum depends on the employee's qualification level and, for high earners, on their pay. The test is the level of training, not experience gained on the job.

Employee's situationTrial period length
Minimum, in every case2 weeks
Training below the CATP / DAP level3 months maximum
General case (training at or above CATP)6 months maximum
Gross monthly pay reaching the high-earner threshold12 months maximum

The threshold that unlocks a twelve-month trial is a gross monthly salary of at least 5,318.41 €, the figure in force since 1 June 2026. Since this amount is index-linked, it is the value applicable on the date the contract is signed that counts. If you are unsure whether a foreign diploma matches the CATP level, it is better to check before fixing the length than to argue about it afterwards.

Ending the trial period: notice and form

During the trial, either side can end the contract without having to justify it and without severance. The termination must be in writing, by registered letter or by hand delivery against signature, in two copies. One major exception: during the first two weeks, no one can end it alone, neither the employer nor the employee, except for gross misconduct. And the gross misconduct relied on must be stated precisely in the letter, or the termination is irregular.

The notice to observe depends on the agreed trial length. The rule has two limbs: if the trial is expressed in weeks, the notice is as many days as there are weeks; if it is expressed in months, it is four days per month of trial, with a floor of fifteen days and a ceiling of one month. The days are counted as calendar days, weekends and public holidays included, and the notice must end before the trial ends. If it runs over, the contract becomes permanent.

Agreed trial lengthTermination notice
2 weeksTermination not possible, except for gross misconduct
3 weeks3 days
4 weeks4 days
1, 2 or 3 months15 days
4 months16 days
5 months20 days
6 months24 days
7 months28 days
8 to 12 months1 month

In practice, a clean termination is planned: you check the trial end date, count the notice backwards from it, and send the letter early enough for the notice to finish within the window. Post the registered letter too late and you are tied into a permanent contract you never decided on.

Sickness, accident or pregnancy during the trial

An employee can fall ill during the trial period. If so, the trial is automatically extended by the length of the absence, whether it is an incapacity for work or leave for family reasons. That extension is capped, however: it cannot exceed one month, even if the absence was longer. Once the extended period has run out, the employer can end the contract again, including while the employee is still on sick leave. The sick employee's duties, informing the employer on the first day and handing in the certificate by the third at the latest, are the same as during the contract, as we set out in our article on sick leave in Luxembourg.

Pregnancy opens a specific protection. From the handing over of the pregnancy medical certificate until the end of maternity protection, the contract cannot be ended; the part of the trial that was still to run then resumes. These safeguards are a reminder that the trial period is flexible, not rule-free.

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The trial period in a fixed-term contract (CDD)

A fixed-term contract can also include a trial period, of at least two weeks, but with a limit of its own: it cannot exceed a quarter of the contract's length, or of its minimum length where the contract has no fixed end date. A long trial therefore eats into the useful term of a CDD, since it counts towards the authorised total. Another rule worth knowing: when a permanent contract follows a fixed-term one on the same post, the permanent contract cannot provide for a new trial period, the employee having already proven themselves. We cover the other rules of the fixed-term contract, maximum duration and renewals included, in our article on fixed-term contracts in Luxembourg.

What the trial period changes for your payroll

The trial period is a matter of employment law, but it has concrete payroll consequences, and that is where our job begins. First thing: the trial delays no social formality. The employee's entry declaration to the Joint Social Security Centre (CCSS) is still due within eight days of the start date, trial or not, and cover begins in the same way. Second point, often missed by employers: during the trial period, the Employers' Mutual Insurance refunds the whole of the continued salary in the event of sick leave, where the ordinary refund is 80%, a mechanism we explain in our guide to sick leave in Luxembourg.

Finally, ending a trial is settled on a final payslip: the month's salary, compensation for accrued but untaken leave, and the exit declaration to the CCSS. Payroll tied to the accounts shows this cost when it happens, not months later. That is the whole point of outsourcing payroll in Luxembourg the way we run it, inside the Odoo where your accounts live. For the drafting and legal soundness of the trial clause itself, on the other hand, a specialist employment-law adviser remains the right contact: we turn decisions into payroll, we do not settle a dispute in your place.

Frequently asked questions

What is the maximum length of a trial period in Luxembourg?

The minimum is 2 weeks. The maximum is 3 months for an employee whose training is below the CATP level, 6 months in the general case, and 12 months for an employee whose gross monthly pay reaches the high-earner threshold (at least 5,318.41 € since 1 June 2026).

What notice is needed to end a trial period?

If the trial is expressed in weeks, the notice is as many days as there are weeks. If it is expressed in months, it is 4 days per month of trial, with a minimum of 15 days and a maximum of one month. The days are counted as calendar days, and the notice must end before the trial ends.

Can the contract be ended in the first two weeks of the trial?

No. During the first two weeks, neither the employer nor the employee can end the contract on their own initiative, except for gross misconduct set out precisely in the termination letter. Free termination only becomes possible after that, with the notice matching the agreed length.

What happens if the employee is sick during the trial period?

The trial is extended by the length of the absence, capped at one month. Beyond that extension, the employer can end the contract even if the employee is still on sick leave. In case of pregnancy, the contract is protected between the handing over of the certificate and the end of maternity protection, the remaining part of the trial resuming afterwards.

Can a trial period be renewed?

No, it cannot be renewed. A length set beyond the legal maximum is only cut back to that maximum, not cancelled. And when a permanent contract follows a fixed-term one on the same post, no new trial period can be provided for.

Further reading

Why Advena?

We keep the accounts and run payroll for Luxembourg SMEs of 1 to 50 employees inside the management tool we deploy ourselves, on a flat fee from 325 € per month, all in. On a trial period, that means an entry declaration filed on time, accurate pay from the first payslip, follow-up of the Employers' Mutual Insurance refund at 100% in the event of sick leave, and, if the trial does not work out, a correct final settlement with the exit declaration. It all flows straight into the Odoo where we keep your books, so the cost of a hire shows up in your position in real time. Let us be plain: we handle the payroll and accounting of a trial period, but the legal drafting of the clause and any dispute belong to an employment-law adviser, and we will tell you so.

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Information up to date as of October 2026, based on the Luxembourg Labour Code (articles L.121-5 for duration, notice and extension, and L.122-11 for the trial period in a fixed-term contract) and on information published by the Inspectorate of Labour and Mines (ITM). The salary threshold that unlocks a twelve-month trial period is an index-linked amount, revisable at each index step. As these rules may change and each situation is specific, this article is for information and does not constitute individualised legal, tax or social advice.