Retroactive Child Support in a Situation where there is a current Child Support Order.

If there is a current child support order, then support is due to the date of the Order if the parent is not making the court ordered payments. You can file a Complaint for Contempt requesting that the Judge make a finding and issue sanctions for failure to pay the obligation that was either a court Order or Judgment and you need to prove that the Order was clear and unambiguous.  Secondly, that the other party unknowingly violated the Order.  Third, you have to in order to prove to get sanctions have to show that the defendant had the ability to pay. If you can prove that support has not been paid as required by the Order, you will be owed money retroactively to the date of the court Order and there can also be interest and sanctions applied.

If on the other hand you are filing to have an increase or decrease in the Child Support Order you have to file a Complaint for Modification where you request that the court, make changes to the prior Order.  You have to prove that there has been a significant material change in circumstances and that the change requires a change in the Order.  This would occur not only after you file the Complaint for the Modification, but when you serve the Complaint.  There is a strong incentive to get your Modification filed as soon as possible and have the other party served as soon as possible because retroactive child support cannot go back earlier than that.