Does the 12 months of service have to be consecutive for FMLA eligibility?

No. The required 12 months of employment do not have to be consecutive. However, time worked more than seven (7) years ago does not count toward eligibility.
If an employee is on paid or unpaid leave and continues to receive benefits like workers’ compensation or health coverage, that time still counts as employment.
Employees who serve in the military (USERRA) receive credit for each month of military service toward the 12-month minimum.
Example:
If an employee works for 9 months, serves 9 months in active military duty, then returns to work, that employee meets the 12-month requirement because both periods count.
For more information, visit the State of Tennessee Attendance and Leave Manual.