According to MOM guidelines,Consultancy is required to file Form IR21 to IRAS department at least one month before last working day of employee.Most of the Consultancy are not following this guideline and holding the Salary of employee for 2-3 Week after last working day.So ideally Consultancy shouldn't wait for employee last day to file Form IR21 to IRAS department as it will delay the final settlement of employee because IRAS will take 1-2 week to process employee TAX only after they receive IR21 Form from Consultancy.Consultancies are deliberately delay this IRAS TAX Filing till employee last working day so that they can hold back our salary for next 2-3 Weeks.So employee must remember to force their consultancy to file IRAS TAX much before his last working day.This will give IRAS department to process that Tax before his last working day and employee will get back his salary within 2-3 days after last working day as IRAS Tax was already processed before his last working day.