When you are ordered to receive child support, (known as an obligee) each month's missed payment becomes a form of a judgment or an arrearage. These unpaid amounts collect interest at the rates provided for in Sec. 55.03 Florida Statutes (2015). If you are not receiving child support when you ought to be, it is very important that you ask your lawyer or the Court to include interest in any contempt/enforcement/judgment award.
This is a very simplified post on a very complex topic and the calculation itself is even more complicated with penalties assessed by the clerk, partial payments, missed payments, lump-sum payments to catch up, etc... We strongly advise you work with a family law professional who has a complete grasp of these issues if you are seeking to modify, enforce, or receive child support in Florida.
As always, we offer a free consultation and would be happy to meet you to discuss how we can help you and your family.