There is actually no legal definition of "full-time" versus "part- time".  The difference in a job being full-time and part-time can be a matter of hours or not. The Fair Labor Standards Act (FLSA) does not define full-time employment or part-time employment. Instead, this is a matter to be typically determined by the employer.  This means that an employer can set their own definition for what part-time means.  So while traditionally, the 40-hour mark is considered to be full-time, it could be classified as part-time (in your case especially since you don't consistently work 40 hours per week). And vice versa, an employee could work 32 hours per week and be classified as being a Full-time employee.  Bottom line, such classifications are at an employer's discretion.  The only exceptions to this would be if there is a stated company policy covering this, or there is a union/employment agreement that governs, or this situation has arisen due to some type of discrimination.Note:  If you're a non-exempt employee, you must be paid for all hours worked whatever they are classified to be; hours over 40, if any, must be paid as overtime.