Child support obligations generally end when the child reaches the age of majority as defined by state law (usually 18-21) or graduates from high school. If a child joins the military or gets married before reaching the age of majority, or successfully petitions the court for emancipation (“to remove the disabilities of minority”), the child will be emancipated and child support obligations will usually be terminated. But the child support obligation in this circumstance does not terminate automatically, and the parent generally must seek an order terminating the support obligation from the court that issued the child support order. And if the child has special needs (health care, living, education) or has not graduated from high school by the age of majority, the parent may be required to pay child support even after the child reaches the age of majority or is emancipated.

In Illinois, child support obligations typically end when a child turns 18, which is the age of majority, or graduates from high school, whichever occurs later. However, if a child is still enrolled in high school upon turning 18, support may continue until the child graduates or turns 19, whichever comes first. If a child marries, joins the military, or is otherwise legally emancipated before reaching the age of majority, the child is considered to be self-supporting, and the parent's obligation for child support may end. Nevertheless, this does not happen automatically; the parent must petition the court that issued the original child support order to terminate the obligation. Additionally, if the child has special needs, the court may order support to continue beyond the age of majority. It's important for parents to be aware that changes in child support obligations are not automatic and typically require a court order.