how is child support calculated under IL child support laws, what is the process and length

The process can be long in that an order for support can not be entered until a paternity case is filed the father admits or is found to be the father and issues relating to verification of his income have been resolved. Please look to state laws 750 ILCS 28 and 750 ILCS 5/505. Im my experience where the alleged father admits he is the dad and he does not dispute my findings as to his child support the order can be entered in about one month and likely an additional 3-4 weeks if his employe cooperates with sending the money to the state disbursement unit.

The case can take many more months if the alleged father attempts to avoid being served, he has worked seasonal jobs or has a large income with several income producing streams or wishes to contest the parentage issue and request DNA tests.

As far as the technical calculation please review state law 750 ILCS 5/505 to understand what constitutes "net income".