In Illinois, the law makes a distinction between parents who were married and parents who never married. Non-married parents are allowed to ask for retroactive child support back to the date of the child’s birth. Married parents cannot.

The theory is that married parents were both supporting the child before the divorce was filed. On the other hand, if the parents were never married, Illinois law presumes the non-custodial parent was not been supporting the child. 

Married parents

For married parents, a general rule in Illinois is that a child is entitled to receive retroactive support starting on the date the court was first asked to award child support. This date is usually after the date that the divorce case was started.

For example:

• Father was served with Divorce Papers on February 1
• Mother filed a motion requesting Child Support on April 1
• The court hearing was held on June 1, and awarded Mother Child Support

In this case, the court can (but may not) award Mother retroactive Child Support starting on April 1, but it would not award her retroactive support back to February 1, and would not go back to the child’s birth.

Unmarried parents

For unmarried parents, Illinois Law (750 ILCS 45/14(b)) mandates that Child Support be ordered retroactive to the date one parent was served with papers.

For example:

• Father was served with Papers to Establish a Father-Child Relationship on February 1
• Mother filed a motion requesting Child Support on April 1
• The court hearing was held on June 1, and awarded Mother Child Support

In this case, the court must award Mother retroactive Child Support to February 1, and could require retroactive payments back to the child’s birth.

In determining whether to award retroactive child support to the child’s birth, the court must consider the following five factors (assume Mother is asking for support from Father in this case):

• Father’s prior knowledge of the facts and circumstances of the child’s birth;
• Father’s prior willingness or refusal to help raise or support the child;
• The extent to which Mother previously informed Father of the child’s needs or attempted to seek or require his help in raising or supporting the child;
• The reasons Mother did not file the action earlier; and
• The extent to which Father would be prejudiced by the delay in bringing the action.

How far back retroactive Child Support will be awarded depends on the facts of your case and the judge who is making the decision. However, in most cases, a general rule of thumb in Cook County is to be to awarded Child Support retroactive for one to two years prior to the case being filed.