Child Support Arrears

The obvious source is missed payments on a current order. Two less obvious ones account for a large share of surprise balances:

• Retroactive support. When an order is first established, many states can reach back and order support for a period before the order existed -- commonly to the date the case was filed, and in some paternity cases further. A parent can be handed a first order and an arrears balance in the same hearing.
• Interest. A number of states charge statutory interest on unpaid support, and those rates were often set decades ago at levels well above current consumer rates. On an old balance, accrued interest can rival or exceed the original principal. Whether interest accrues at all, at what rate, and whether it can be waived are all state-law questions.
• The gap between a life change and a filing. Support keeps accruing at the ordered amount until a court changes it -- see below.

• They generally cannot be retroactively reduced. Federal law -- the provision usually called the Bradley Amendment, codified at 42 U.S.C. § 666(a)(9) -- requires every state to treat each support installment as a judgment by operation of law as it comes due, not subject to retroactive modification. A judge cannot simply forgive support that already accrued, even one who thinks the old order was set too high.
• They survive bankruptcy. A domestic support obligation is excepted from discharge under 11 U.S.C. § 523(a)(5) and is a first-priority claim under § 507(a)(1). Filing bankruptcy can clear the other debts competing for a parent's income, but it does not clear the support arrears themselves.
• They stay collectible for a long time. Many states allow enforcement for years or decades after the child turns 18, and several impose no limitations period on collecting support arrears at all. "The kids are grown" is not a defense to a balance.

Because federal funding conditions require every state to adopt a common toolkit (42 U.S.C. § 666), the enforcement mechanisms look broadly similar nationwide, even where the procedure and the amount of court discretion differ:

• Income withholding. Support is normally taken directly from wages, using a standard federal Income Withholding for Support order that an employer in any state must honor. How much can be taken is capped by the Consumer Credit Protection Act (15 U.S.C. § 1673(b)): up to 50% of disposable earnings if the parent is supporting another spouse or child, 60% if not, each rising five points (to 55% and 65%) once support is 12 or more weeks in arrears. States may set lower caps, and many do -- the federal figure is a ceiling, not a target.
• Tax refund offset. Certified arrears are intercepted from federal tax refunds through the Treasury Offset Program, generally at a threshold of $150 for cases with assigned (public-assistance) arrears and $500 otherwise. Most states run a parallel program against state refunds and, in some places, lottery winnings.
• Liens and account seizure. States must provide for liens arising by operation of law against real and personal property (§ 666(a)(4)) and run periodic data matches against financial institutions to locate and freeze accounts (§ 666(a)(17)).
• Credit reporting. States are required to report overdue support to consumer reporting agencies (§ 666(a)(7)), which is why arrears frequently appear on a credit file without the parent having applied for anything.
• License suspension. Every state must have procedures to withhold, suspend, or restrict driver's, professional, occupational, and recreational licenses over overdue support (§ 666(a)(16)).
• Passport denial. Under 42 U.S.C. § 652(k), a parent with $2,500 or more in certified arrears can be denied a new or renewed U.S. passport, and in some cases have an existing one revoked. That $2,500 is a single federal statutory threshold -- it is not a state-by-state number, and it does not scale with the size of the underlying order.

Persistent non-payment can also be pursued as civil contempt, which carries the possibility of jail. The Supreme Court addressed that in Turner v. Rogers, 564 U.S. 431 (2011): an indigent parent facing civil contempt is not automatically entitled to appointed counsel, but the court must use adequate procedural safeguards and must actually make a finding on that parent's ability to pay. Documented inability to pay is a defense to contempt -- it is not a defense to the balance itself.

• A job loss or pay cut, by itself. The order stays fully enforceable at the old amount until a court modifies it, and most states will not apply a modification retroactively to any date before it was filed. Waiting to file, rather than filing as soon as circumstances change, is the single most common way a balance builds. See how modification works.
• An informal agreement between the parents. Direct payments, a reduced amount the other parent verbally accepted, or support handed over in cash are frequently treated as gifts rather than credited against the order, because the order directs payment through the state disbursement unit. Any agreed change needs to be entered as a court order to count.
• The child turning 18 or the order ending. Emancipation stops future support from accruing. It does not touch what already accrued, and collection continues afterward.
• Being denied parenting time. Support and access are separate obligations in every state. Withheld visitation is a serious problem with its own remedy -- it is not authorization to stop paying.

• Filing for modification immediately. It cannot undo what has already accrued, but it stops the balance from growing at a rate the parent cannot pay. Filing the week of a job loss rather than six months later is frequently a difference of thousands of dollars.
• An arrears compromise, where the debt is owed to the state. Arrears split into two kinds: support assigned to the state to reimburse public assistance, and support owed to the other parent. Many state child support agencies run debt-compromise or arrears-forgiveness programs for the state-owed portion, usually conditioned on the parent staying current going forward. The portion owed to the other parent can generally only be forgiven by that parent, in writing, and entered as an order.
• Correcting the arithmetic. Balances built over many years across multiple payment channels are not always right. Requesting a formal account audit from the enforcement agency, backed by the parent's own payment records, is a legitimate and frequently overlooked step.
• Incarceration, in most states. Federal regulation 45 CFR 302.56(c)(3) prohibits states from treating incarceration as voluntary unemployment when establishing or modifying an order, which is what makes a modification during a sentence possible rather than automatically refused. The order still has to actually be modified -- see imputed income for how earning capacity gets assigned when a drop in income is not involuntary.

Enforcement services through a state's Title IV-D child support agency are available to any parent, not only those who have received public assistance, and applying is typically free or nearly so. The agency can run wage withholding, tax offset, license actions, and interstate enforcement on your behalf without you retaining counsel. It is usually slower than private enforcement and gives you less control over strategy, but it reaches collection tools -- federal offset and passport certification in particular -- that a private attorney cannot invoke directly.