All the FMLA does is guarantee your job when time off is needed to take care of medical issues for you or members of your immediate family. The law provides up to 12 weeks per year, after an employee is eligible. Employers determine when leave falls under the FMLA, not the employee, based on the mandates of the law. PTO is normally charged when there is a balance on the books, otherwise the Act mandates that medical time off can be unpaid. In the federal system, when taking leave under FMLA, it will be PTO until your balance hits zero. Then it is unpaid unless co-workers donate time off of their balance. Most private entities are held to the same standard and are subject to the FMLA.