Go to Settings - Salary items :



Position yourself on the item  (DO NOT uncheck it):



On the Global tab, (which becomes grey as soon as the item has already been used), the item type must be Family allowances (contribution to compensation fund)  and the field Social deductions item must be ticked..


In the tab Computation elements, the box Active for minors must be unchecked and the box Active for pensioners must be checked. The amount of the OASI pensioners deduction must be indicated.

The box End of period rectification must also be ticked.

The insurance contract must be the one that was defined. (In case of doubt about the it, see here)


On the Employer's part, indicate the contribution rate to be applied to the employee's salary: 



On the Employee's share, indicate the contribution rate to be applied to the employee's salary: 



0 except for Valais which is the only canton in Switzerland where employees also contribute.


In the tab Applied to, you will find the items to which the contribution is applied : 


On the Subject to tab, there would be items to which the it would be subject. Therefore, there are no items checked:




On the Statistics/Certificate tab, the Group of fields is Social contributions and the box Contributions OASI must be checked (just matters for canton valais)