Jurilo by Lawise.ai:
Changes can occur during the course of an employment relationship: salary adjustments, reduction of working hours, or changes in function. Such contract modifications are generally possible in Switzerland – but not unilaterally. In this article, you will learn when a contract modification is permissible, how it is correctly implemented, and what rights employees and employers have in this regard.
WHAT IS A CONTRACT MODIFICATION IN EMPLOYMENT LAW?
A contract modification occurs when essential components of the employment contract are changed. These include in particular:
Salary (increase or reduction)
Working hours (e.g., from 100% to 80%)
Function or scope of duties
Place of work
Working time model (e.g., switch to shift work)
Such changes generally require the consent of both parties.
MUTUAL CONTRACT MODIFICATION IN THE EMPLOYMENT CONTRACT
Written agreement
The simplest and legally safest form is the mutual contract modification. Both parties agree on the new conditions and record them in writing – e.g., in an addendum to the employment contract.
Example: The employee requests a reduction in working hours to 60%, the employer agrees. The change is confirmed in writing.
UNILATERAL CONTRACT MODIFICATION BY THE EMPLOYER
Modification termination: Requirements & procedure
If the employer wants to unilaterally change the employment contract (e.g., salary reduction, new function), they cannot simply order this. Instead, they must issue a so-called modification termination:
Termination of the existing contract
Simultaneous offer of a new contract with modified conditions
In compliance with the notice period
The employee can accept or reject the new offer. If they reject it, the employment relationship ends after the notice period expires.
Requirements for a valid modification termination
Compliance with the notice period according to Art. 335c CO
No termination at an inopportune time (Art. 336c CO)
No abusive termination (Art. 336 CO)
Proportionality and objective reason
CONTRACT MODIFICATION BY THE EMPLOYEE
The employee can also propose a contract modification – e.g., a salary increase or a reduction in working hours. However, the employer is not obligated to agree. If no agreement is reached, the existing contract remains in force.
DIFFERENCE BETWEEN RIGHT TO ISSUE INSTRUCTIONS VS. CONTRACT MODIFICATION
Not every adjustment is a contract modification. Minor changes in the scope of duties or place of work may be covered by the employer's right to issue instructions. However, as soon as salary, working hours, or function are significantly affected, a contract modification requiring consent is involved.
WHEN IS A CONTRACT MODIFICATION ABUSIVE?
A contract modification can be abusive if it:
is used as a means of pressure to force termination
is discriminatory or harassing
is made without objective reason
👉 Unclear about contract modifications in the employment contract?
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👉 See also: Termination by employer vs. employee – Switzerland
👉 Related: Fixed-term vs. permanent employment contract – Differences
👉 Basics: Employment contract Switzerland – Content & legal basics
CONCLUSION
Contract modifications are possible in Switzerland, but only with the consent of both parties or within the framework of a modification termination. Employers should communicate changes transparently and record them in writing. Employees should carefully review changes and seek legal advice if uncertain.
FAQS ON CONTRACT MODIFICATION: SALARY, WORKING HOURS, FUNCTION
Can my employer simply reduce my salary?
No. A salary reduction is only permissible with your consent or within the framework of a modification termination. A unilateral salary reduction is invalid.
What is a modification termination?
This is when the employer terminates the existing contract and simultaneously offers a new contract with modified conditions. The employee can accept or reject this.
Does a contract modification have to be in writing?
Not mandatory, but for evidentiary reasons, a written agreement is strongly recommended – especially for changes to salary, working hours, or function.
Can I reject a contract modification?
Yes. If you do not agree with the proposed change, you do not have to accept it. The employer may then issue a modification termination if applicable.
What happens if I reject a modification termination?
Then the employment relationship ends after the notice period expires, provided the termination was lawful.
Can my employer change my function?
Only with your consent or within the framework of a modification termination. However, minor adjustments in the scope of duties are permissible if they are covered by the right to issue instructions.
Can I reduce my working hours?
You can request a reduction, but the employer does not have to agree. There is no legal entitlement to part-time work (except in special cases, e.g., maternity).
What if I sign a contract modification but later regret it?
A contract modification once signed is binding. Withdrawal is only possible with the employer's consent or under special circumstances.
Is a verbal contract modification valid?
Yes, verbal changes are generally valid. However, they are difficult to prove – therefore every change should be recorded in writing.
Can I take action against an abusive contract modification?
Yes. If the modification is discriminatory, harassing, or made without objective reason, you can defend yourself against it – e.g., through rejection, legal action, or appeal to the conciliation authority.
