What is "back child support"?

If you do not live with your child and you do not help support your child, you may be ordered to pay “back” or “retroactive” child support to the person who cared for your child. This is true even if there is no prior court order. If there is a court order and you do not pay child support as ordered, you will be ordered to repay the child support “arrears” ("back child support") with interest.