It is never required to ask for child support, if you can meet the child's needs on your own, you are certainly entitled to not seek support. If the parties have an agreement between themselves, that they honor certainly that is to everyone's benefit. It is always best for everyone if they agree on how they are going to deal with these issues. You do need to be aware that a verbal agreement is not likely enforceable, and there really is not back support, child support runs from the date that a petition is filed seeking support. Parents can decide that they do not wish to file or seek support, in effect waiving support, however, you may not as a matter of public policy specifically waive future child support. Even if you reach an agreement that does this, the courts cannot enforce that agreement. One reason for that is if the child becomes a public charge, ie he is receiving DSS benefits, the government must have the ability to seek reimbursement for those monies. Second the child has a right to be supported by both parents and one parent cannot give that right away on behalf of the child.
If there are public welfare benfits being paid to the child, child support is likely mandatory otherwise the answer is no. However, I think it may be against public policy for a parent to permanently waive child support, therefore even if child support is not currently being paid, the custodial parent can always go back to Court and plead changed circumstances.
In Wa. State, parties are required to file child support worksheets and financial declarations once court action is initiated. Parents have a statutory obligation to support their children. A court will order child support based upon the net incomes of the parties once the matter goes to trial if no temporary hearings have been held prior to that time. Please note that child support laws are different in every state so it is important that any advice you get on this issue originates from an attorney practicing law in Wa. State.
The amount of child support to be paid can be agreed to as long as the amount is as set forth in the child support guidelines. You may ask to deviate from those guidelines, but there are specific statutory criteria that the court must consider before ordering a deviation.
If no party has initiated court action, the state is not involved in monitoring whether or not a parent is supporting their child, so there may be no court order but the obligation still exists.
Hope this helps