As indicated in section 6.6 of the directives concerning withholding taxes of the Canton of Geneva, the salary certificate can be used as a withholding tax receipt if certain information is included in section 15.
The trigger for this printout can be found at the employee level in tab 6 (Salary certificate - Texts and amounts).
It is also possible to check the box directly in the company settings and it will apply this printing only for the people concerned by the canton of Geneva :
