In most states the parents of a minor child may agree to the amount of child support, and courts encourage the parents to do so. But the court will generally review the agreed amount of child support and determine whether it is in the best interest of the child before signing a child support order. And if the parents later agree to change the amount of or need for child support, they should return to court and get a signed order that reflects the agreed or changed amount, as only the court may change the legal obligation under a child support order.

In California, parents of a minor child can negotiate and agree upon the amount of child support. This collaborative approach is encouraged as it often leads to more amicable arrangements and reflects the parents' understanding of their child's needs. However, any agreement reached must be reviewed and approved by a court to ensure that it serves the best interests of the child. The court will consider California's child support guidelines to determine if the agreed amount is appropriate. If parents wish to modify the child support amount or the need for support changes, they must petition the court for a modification of the existing order. The court will then review the new circumstances and decide whether to approve the revised child support amount. It is important to note that only a court can legally alter the obligations set forth in a child support order, and informal agreements between parents without court approval do not change the legal responsibilities.