Child support generally may be changed or modified by filing a motion to modify and demonstrating to the court that the circumstances of the child or one or both parents have materially and substantially changed, or that some period of time (3 years, for example) has passed since the court’s last child support order. And if there has been a material and substantial change in the custody of the child—if, for example, the noncustodial parent who was paying child support has become the custodial parent—the court may change or eliminate the child support obligation based on the change in the custody arrangement.
In Washington State, child support orders can be modified if there has been a 'material and substantial change' in the circumstances of the child or either parent since the last child support order was entered. This could include significant changes in income, changes in the needs of the child, or changes in the residential schedule. Additionally, if it has been three years or more since the last order, a review can be requested even without a substantial change in circumstances. If there is a change in custody, such as the noncustodial parent becoming the custodial parent, this could also be grounds for modifying the child support obligation. To initiate a modification, a motion must be filed with the court, and the requesting party must demonstrate the change in circumstances to the court's satisfaction for the modification to be granted.