Under Singapore tax law, where a non-Singaporean employee of the Company terminates employment with the Company in Singapore, goes overseas or plans to leave Singapore for more than three months, the Employer must notify the Singapore Revenue Authority (IRAS) at least one month prior to the event, and withhold all monies due to the employee from the date the Employer became aware of the impending termination of employment or departure from Singapore. In Singapore, this process is called Tax Clearance.
For the purpose of IRAS notification, the Employer is required to file the IR21 form at least one month before the non-Singaporean employee leaves for an overseas assignment or leaves Singapore for a period of more than three months.
Find out more about Tax Clearance on the IRAS website