Ill. Admin. Code tit. 56, § 200.220 – Accruing Paid Leave Over a 12-Month Period

a) If an employer requires employees to earn paid leave hours via accrual, an employee is entitled to accrue paid leave hours at the rate of one hour of paid leave for every 40 hours worked during a 12-month period up to a minimum of 40 hours of paid leave over the same 12-month period. [820 ILCS 192/15] An employer may choose to provide leave in smaller, proportional, increments, if the rate of benefit accrual is at least 1 hour of paid leave for every 40 hours worked. For the purpose of this Section, work periods must be counted on a minute-by-minute basis or may be rounded up to the next 15 minutes. An employer may not round down time worked.
b) Except as provided in subsection (c), an employer is required to count all time that an employee works, including overtime hours worked, for purposes of calculating accrual. An employer is not required to count time when an employee is on paid or unpaid leave or other non-compensable time where the employee is not performing work for the employer as time worked for accrual purposes.
c) Employees exempt from the overtime requirements of the federal Fair Labor Standards Act (29 U.S.C 213(a)(1)) shall be deemed to work 40 hours in each workweek for purposes of paid leave time accrual if that employee regularly works 40 or more hours in a workweek. [820 ILCS 192/20] If such employee's regular workweek is less than 40 hours, the employee's paid leave time accrues based on the number of hours in their regular workweek.
1. 1) An overtime-exempt employee who regularly works 40 hours or more in a workweek is entitled a minimum of 40 hours of paid leave during a 12-month period.
2. 2) An overtime-exempt employee who regularly works less than 40 hours in a workweek is entitled to accrue paid leave hours based on the number of hours worked in that workweek consistent with Sections 200.200 and 200.220.
d) Accrual calculation examples.
EXAMPLE A: Employee A works 15 hours per week, 52 weeks per year. Employee A is entitled to accrue 19.5 hours of paid leave annually. (15 times 52 = 780 hours worked per year. 780 divided by 40 = 19.5 hours of paid leave time.)
EXAMPLE B: Employee B works 50 hours per week, 52 weeks per year. Employee B is entitled to accrue at least 40 hours of paid leave annually. Employee B's employer may choose to provide more than 40 hours, either via accrual or frontloading.
EXAMPLE C: Employee C is paid on a salary basis and qualifies for the "administrative" exemption under the Fair Labor Standards Act. Employee C's office hours are regularly 37.5 hours per week, but in some weeks, this employee's work hours may be fewer or more, depending on workload. Employee C's employer requires employees to earn paid leave via accrual. Employee C's paid leave shall accrue on the basis of 37.5 hours per week, even in weeks when they work fewer hours.