On October 7, 2015 at 9:15 am Jennifer M. Long, B.A. J.D. said: Typically, in awarding retroactive child support, the case law differs from case to case. Some judges will order about 3 years retroactive; others will order less or more. This situation is often very much fact-driven and based on the circumstances. For example, if you have been requesting child support or even disclosure of income from your ex to determine child support for 5 years without cooperation, then a court may very well order retroactive child support for 5 years. Some of the factors include how the children have been cared for financially, whether the parent with the children has had to incur debt because of no or inadequate child support, whether the parent seeking child support gave NOTICE to the other that he/she is seeking child support and when that notice was given, etc. Since this issue depends on so many factors, I recommend that you speak with a lawyer in greater detail about your situation.