Illinois law provides that all provisions related to support of the children are always modifiable. Typically, child support is calculated pursuant to the percentage guidelines as set forth by the Illinois Marriage and Dissolution of Marriage Act (IMDMA) after reviewing the “net income” of the non-custodian parent. Section 750 ILCS 5/505 of the IMDMA governs child support in Illinois. The Court will apply these statutory percentage guidelines in every case unless the Court makes a specific finding that it would be inappropriate, after considering the best interests of the child in light of the evidence, including such things as the financial resources and need of the child; the financial resources and needs of the custodial parent; the standard of living the child would have enjoyed had the marriage not been dissolved; the physical and emotional condition of the child, and his educational needs; and the financial resources and needs of the non-custodial parent. “Net income” for purposes of calculating child is support, is defined as the income from all sources (including second jobs, overtime, holiday pay, etc.) not including the following deductions:

(a)Federal income tax (which has been properly calculated);

(b)State income tax (which has been properly calculated);

(c)Social Security (FICA payments);

(d)Mandatory retirement contributions required by law or as a condition of employment;

(e)Union dues;

(f)Dependent and individual health/hospitalization insurance premiums;

(g)Prior obligations of support or maintenance actually paid pursuant to a court order;

(h)Expenditures for repayment of debts that represent reasonable and necessary expenses for the production of income, medical expenditures necessary to preserve life or health, reasonable expenditures for the benefit of the child and the other parent, exclusive of gifts.

If the net income of the non-custodial party cannot be ascertained because of default or any other reason, the Court shall order support in an amount considered reasonable in the particular case. This is frequently called “needs based” order. Generally, a needs based order tends to be more than a guideline support order.

To modify an existing order setting a child support obligation, a judge must find that there has been a “substantial change in circumstances.” Some of the factors that the court will likely consider in making this determination are: 1) have the needs of the children changed; 2) have the needs of either the supporting or receiving parent changed; 3) has there been a change in custody; and 4) has one of the children reached the age of majority or has completed his or her high school education. Child support obligations may only be modified by a judge. Although in many instances, the parties may agree on a modification on their own; any agreements made between the courts without entering a court memorializing such an agreement may not be enforceable in the event issues arise from non-payment of support. Often times, a non-custodial parent who has a support obligation assumes that the support obligations will automatically terminate once the child reaches the age of eighteen years. This is not always true, it is advisable that the non-custodial parent file a motion with the court to have a court order formally terminating any support obligations and such a motion should be filed in advance of a child’s eighteenth birthday so that there are no overpayments of child supports to the custodial parent.