You're probably already familiar with deductions for payroll taxes and Social Security, but there are a growing number of deductions which employers can legally withhold from your paycheck. However, only certain types of deductions can be legally withheld, and even then, the amount and/or percentage of the deduction is often limited by federal and state laws. Other types of withholding can be legally withheld only with your written permission and cannot be deducted if you have not authorized the deductions.