Child Support Arrears
"Arrears," or "back support," are child support amounts that came due but were not, for whatever reason, paid. They may be for amounts owed prior to the establishment of an order or they may be due to missed payments. In either case, they don't go away when the regular order terminates. While you may feel like you're paying to support an adult child, in reality you are effectively repaying the custodial parent for her expense in making up your share of support when your child was a minor.
In some states, child support arrears include added interest. Because of this, the balance you owe may be more than the regularly scheduled payments you missed. Depending upon the laws of your state, interest may continue to accrue until the balance is paid in full. In other states, such as North Carolina, child support arrears do not accrue interest. Noncustodial parents in these jurisdictions effectively receive the benefit of interest-free loans from the other parent.
Payments After Emancipation
Exactly how your payments will be handled after your child ages out of regular support depends upon your state and, in some cases, your county. In some states, such as Nevada, child support payments remain the same as they were under the old order and go entirely to arrears. In other states, the payments may drop, since the current support amount is no longer included. At the point when a child emancipates, some courts may be inclined to lower payments to more manageable levels, since the custodial parent no longer has to support the child and the child's need to receive support from his parents is presumably lower.
Satisfaction of Arrears
Child support payments will continue until the arrears balance is paid in full, but you may have some options for paying them off sooner. Some states offer compromise programs where interest stops accruing or options exist for settling for less than full payment. If you're making direct payments to the other parent instead of paying through the court, you may propose a lump-sum payment of a lesser amount than the total arrears balance. The idea behind a lump-sum settlement is the time value of money; for a variety of reasons, some custodial parents would prefer to receive a certain sum of money up front rather than a lesser amount trickled in over time.