The court that issued the original (or most recent) child support order generally has the sole authority to hear future disputes related to the modification or enforcement of the child support order—provided the child still resides in the same state. This authority to modify or enforce the original child support order is known as jurisdiction, and the court is said to have continuing exclusive jurisdiction over the child support matters. The court with such continuing exclusive jurisdiction is typically the court in which the parents’ divorce case filed—or if the parents were not married, the court in which the suit affecting the parent-child relationship (SAPCR) was filed (suit to determine parentage or suit to establish paternity).

If the child no longer lives in the state that issued the original (or most recent) child support order, the Uniform Interstate Family Support Act (UIFSA) will determine whether the court that issued the child support order has continuing exclusive jurisdiction, or if the court in the state where the child currently resides will have jurisdiction over modification and enforcement of the child support order.

In Washington State, the court that issued the original or most recent child support order typically retains the authority to hear any future disputes regarding the modification or enforcement of that order, as long as the child continues to reside in Washington. This concept is known as continuing exclusive jurisdiction. The court with continuing exclusive jurisdiction is usually the one where the divorce case was filed for married parents, or where the suit affecting the parent-child relationship (SAPCR) was filed for unmarried parents. However, if the child has moved out of Washington, the Uniform Interstate Family Support Act (UIFSA) comes into play to determine jurisdiction. Under UIFSA, the original court may retain jurisdiction if both parents consent or if it is the home state of the child, or jurisdiction may shift to the state where the child currently resides, depending on specific circumstances outlined in the Act.