There are four methods to determine proper calculation of leave use during a 12-month period. These methods have been defined under the Family and Medical Leave Act (FMLA).

The FMLA permits the employer to select the desired method of calculation; however, once selected, the employer must follow the calculation method consistently. Any changes in a selected method once implemented requires an employer to notify all employees of the pending change not less than 60 days in advance of the effective date. Pros and cons for each method are discussed.

Rolling Backward 12-Month Period Calculator

This method calculates the remaining balance from 12 weeks minus any hours taken under FMLA leave during the preceding 12 months as of the date a leave is requested.

Pro:      Employees cannot “stack” leave. However, this is the most common approach and therefore considered a favorable and best-practice method.

Con:     Administration can be more complicated and employees are likely to have a variation in leave cycle time periods.

Calendar Year Calculator

This calendar year method is considered one of the easier methods to administer. A simple calendar, any time requested between January and December is considered as eligible up to 12 weeks.

Pro:     Ease in administration.

Con:    Employees can “stack” leave potentially taking more leave than might otherwise be considered as eligible in a given 12-month period. For example, an employee can return from a 12-week leave in December and request a new leave in January.

Fixed 12-Month Calendar Year Calculator

Another one of the easier methods to administer. This method is a simple calendar or other determined 12-month period. This method might be considered for purposes of aligning with a state law, fiscal year, service tenure (anniversary), or benefit enrollment year.

Pro:     Easier to administrate and permits an option to align to a different key date period.

Con:    Employees can “stack” leave potentially taking more leave than might otherwise be considered as eligible in a given 12-month period. For example, an employee can return from a 12-week leave in December and request a new leave in January.

Rolling Forward 12-Month Period Calculator

This method is measured forward from the date any employee’s first FMLA leave begins. Therefore, each employee may have a different 12-month period, similar to the Rolling Backward method.

Pro:     Easier to manage administratively.

Con:    Employees can potentially “stack” leave.