(40 ILCS 5/17-131) (from Ch. 108 1/2, par. 17-131)
    Sec. 17-131. Administration of payroll deductions.
    (a) An Employer or the Board shall make pension deductions in each pay period on the basis of the salary earned in that period, exclusive of salaries for overtime, extracurricular activities, or any employment on an optional basis, such as in summer school.
    (b) If a salary paid in a pay period includes adjustments on account of errors or omissions in prior pay periods, then salary amounts and related pension deductions shall be separately identified as to the adjusted pay period and deductions by the Employer or the Board shall be at rates in force during the applicable adjusted pay period.
    (c) If members earn salaries for the school year, as established by an Employer, or if they earn annual salaries over more than a 10-calendar month period, or if they earn annual salaries over more than 170 calendar days, the required contribution amount shall be deducted by the Employer in installments on the basis of salary earned in each pay period. The total amounts for each pay period shall be deducted whenever salary payments represent a partial or whole day's pay.
    (d) If an Employer or the Board pays a salary to a member for vacation periods, then the salary shall be considered part of the member's pensionable salary, shall be subject to the standard deductions for pension contributions, and shall be considered to represent pay for the number of whole days of vacation.
    (e) If deductions from salaries result in amounts of less than one cent, the fractional sums shall be increased to the next higher cent. Any excess of these fractional increases over the prescribed annual contributions shall be credited to the members' accounts.
    (f) In the event that, pursuant to Section 17-130.1, employee contributions are picked up or made by the Board of Education on behalf of its employees, then the amount of the employee contributions which are picked up or made in that manner shall not be deducted from the salaries of such employees.
(Source: P.A. 101-261, eff. 8-9-19.)