In Talenox, there is a "Work Pass Worker Category" field that you will need to complete before Payroll is able to calculate Foreign Worker Levy (FWL) accurately.
These are the following options that corresponds in Talenox with MOM's definition of skilled workers:
Higher-skilled: "Skilled" option in Talenox
Basic-skilled: "Unskilled" option in Talenox
To determine if your workers are skilled/unskilled, you'll need to view this official article by MOM to evaluate and select the correct option.
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If you require more information, we would suggest for you to contact MOM directly for better clarity. 😄