The paying parent may petition the court for a modification of his or her child support payment. For the court to grant a modification, you must prove that a substantial change in your circumstances – or the circumstances of your ex-spouse or child – must have occurred since your last support order became effective.
There is a presumption that a support order over three years old is subject to modification if there is a 15% difference between the amount currently ordered to be paid and the amount that would be paid if based on a current application of the guidelines recalculating the parent’s current income.