When is social security tax withheld and why for student workers?
Social Security regulations require that social security taxes be withheld from workers whose primary purpose is work. When student workers limit work to 20-30 hours, the government accepts that their primary function is school work and allows them to be exempt from the withholding taxes. When student workers work 40 hours per week on a regular basis, the government does not accept them being classified as students as their primary function, and therefore requires that social security taxes be withheld. Students who work during the summer months and are not enrolled in any courses are subject to Social Security withholdings.
