There are many complex guidelines, but simply stated, the ACA defines full time as working, on average, 30 or more hours per week. For employees expected to work 30 or more hours per week upon hire, their full-time status begins immediately. Employees who work a varied number of hours or who are not expected to work 30 or more hours upon hire are evaluated annually in the fall, or after a year of employment, to determine full-time status as defined by the ACA.