An addendum is a written change to the employment contract signed by both parties. You need one when you change something that is in the contract, such as the schedule, working hours or pay: that requires the employee's agreement. This template covers a new schedule, weekly working hours and gross pay. It is in Dutch and French.
When you and the employee change something in the contract: other hours, more or fewer hours, different pay. Adapted work or other hours after an illness are also arranged with an addendum the employee signs, because during incapacity for work you do not change the contract unilaterally. If a part-time employee's working hours change, the addendum also states the new part-time schedule.
Name the parties and refer to the original contract and its date.
Write exactly what changes and from which date, and whether the change is temporary or permanent.
Have both parties sign before the change takes effect, and give each a copy.
Adjust the payroll. If the new schedule is not among the schedules in your work rules, you also amend the work rules.
Below is the Dutch text, as used in Flanders. The fields to fill in are in square brackets. In the Word file they are highlighted.
Addendum bij de arbeidsovereenkomst van [datum] tussen [werkgever] en [werknemer]
Opgemaakt in twee exemplaren te [plaats] op [datum]. Handtekening werkgever, handtekening werknemer.
This template gives general information and follows the rules in force on 8 October 2026. It is not legal advice, and no rights can be derived from it. Your joint committee, your work rules and the facts of your case may call for a different text.
Employment contract addendum
Your dedicated contact at Business Centrum looks at it for your situation, together with Acerta, before you send it.