§ 606. Action to recover maintenance, child support, and suit money; sanction for noncompliance
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(d) In lieu of interest on unpaid child support which has accrued under a child support order, a child support surcharge shall be imposed on past-due child support. The surcharge shall be computed and assessed monthly at a rate of one percent or an annual rate of 12 percent and shall not be compounded. All surcharges shall be deemed principal and not interest. Payments received for child support obligations shall be allocated and distributed as follows:
(1) first to current support obligations;
(2) second to arrearages; and
(3) third to surcharge arrears.