Child support amounts vary by state and depend on each parent's income

There is no single federal child support amount that applies across all 50 states. Each state sets its own guidelines, and within those guidelines, the amount owed depends primarily on how much each parent earns, how much time each parent spends with the child, and the number of children involved. A judge or child support officer uses a state-specific formula to calculate what one parent owes the other.

The most common approach is called the income shares model, used by most states. Under this model, both parents' incomes are added together, and the court determines what percentage of combined household income should go toward child support. That total is then divided between the parents based on how much each one earns and how much custody time each one has. A parent earning 60% of the household income typically pays roughly 60% of the calculated support amount.

Some states use different models — a few still use the percentage of income model, where support is straightforward a percentage of the paying parent's gross income (often 17% for one child, 25% for two, and so on). A handful use a combined income model. The state where the child lives, or where the support order was first issued, determines which formula applies.

Key Takeaways

  • Child support amounts are set by state law, not federal law, so the amount owed in Texas differs from the amount owed in New York or California.
  • Most states use the income shares model, which adds both parents' incomes and calculates support as a percentage of that total.
  • The paying parent's gross income, the receiving parent's income, custody time, and the number of children all affect the final amount.
  • You can find your state's child support guidelines on your state's child support enforcement agency website or through your state court system.
  • Child support orders can be modified if either parent's income changes significantly or custody arrangements change.

How states calculate the base support amount

Most states publish a child support guideline table or worksheet that shows the base support obligation for different income levels and numbers of children. For example, a state might say that for combined parental income of $5,000 per month and one child, the base support obligation is $900 per month. That $900 is then divided between the parents based on their individual income shares.

If one parent earns $3,000 per month and the other earns $2,000 per month, the first parent pays 60% of the $900 ($540) and the second parent pays 40% ($360). However, the parent with primary custody typically does not pay support to themselves, so only the non-custodial parent's share becomes the actual child support order. In this example, if the first parent has primary custody, the second parent would owe $540 per month.

States also account for parenting time. If both parents share custody roughly equally, the support obligation may be reduced or adjusted. Some states lower the paying parent's obligation by a percentage for each overnight the child spends with them. Others use a threshold — if the non-custodial parent has the child at least 40% of the time, the calculation changes.

Income that counts toward child support

Child support is based on gross income, not take-home pay. Gross income typically includes wages, salary, bonuses, commissions, self-employment income, rental income, and income from investments. It usually does not include Social Security benefits, Supplemental Security Income (SSI), or Temporary information for Needy Families (TANF).

States differ on whether unemployment benefits, workers' compensation, or disability payments count. Some states exclude them; others include them. If a parent is self-employed, the court looks at net self-employment income (revenue minus legitimate business expenses) rather than gross revenue.

A parent cannot straightforward quit a job to lower child support. If a court believes a parent deliberately reduced income to avoid support, the judge may impute income — that is, assign an income level based on what the parent could earn, not what they currently do earn. This is common when a parent quits a job without a legitimate reason or takes a dramatic pay cut.

Adjustments and add-ons beyond the base amount

The base child support amount covers ordinary living expenses — food, housing, utilities, and basic clothing. But most states allow the court to order additional payments for specific costs. These typically include health insurance premiums for the child, unreimbursed medical and dental expenses, childcare costs needed so the custodial parent can work, and school tuition or special education needs.

Some states build these costs into the base calculation; others treat them as add-ons on top of the base amount. A few states have a cap on income — they calculate support only on income up to a certain level (for example, $250,000 per year) and leave amounts above that to the judge's discretion. This prevents extremely high earners from paying astronomical support amounts based on a rigid formula.

If a child has special needs or significant medical expenses, or if one parent has a much higher income than the other, a judge can deviate from the guideline amount. The court must document why it is departing from the formula, but it has the authority to do so.

How to find your state's specific guidelines

Your state's child support enforcement agency publishes its guidelines online. You can search "[your state] child support guidelines" or visit your state's Department of Human Services, Department of Social Services, or equivalent agency website. Most states also post a child support calculator tool that lets you enter income figures and see an estimated amount.

These calculators are educational tools and do not create a legal obligation. A court order is what creates the actual obligation. But the calculator shows you how your state's formula works and gives you a rough idea of what a judge might order.

If you are involved in a child support case, your state's child support enforcement office can provide you with a copy of the guideline table and explain how it applies to your situation. You can also consult a family law attorney in your state, who will know the current guidelines and any recent changes to state law.

Modification when income or circumstances change

A child support order is not permanent. Either parent can request a modification if there has been a significant change in circumstances. A substantial and material change typically means a change in income of 10% or more, a major shift in custody time, or a change in the number of children for whom support is owed.

If a paying parent loses a job, gets a significant raise, or has a major reduction in income, they can file a motion to modify. If a custodial parent's income increases substantially, the paying parent can request a reduction. If custody changes — for example, if the child moves to live primarily with the other parent — support can be recalculated.

The process for requesting a modification varies by state. Some states allow you to file directly with the court; others require you to go through the child support enforcement agency. You cannot straightforward stop paying while waiting for a modification hearing. If you do not pay, arrears (back support) accumulate, and you may face enforcement actions including wage garnishment, license suspension, or contempt of court charges.

Frequently Asked Questions

Does child support end when the child turns 18?

In most states, yes — support ends when the child reaches the age of majority, usually 18. However, some states extend support through age 19 or 20 if the child is still in high school. A few states require support to continue if the child attends college. The state where the order was issued determines the end date.

What if the paying parent lives in a different state?

The Uniform Interstate Family Support Act (UIFSA) allows one state to enforce a child support order issued in another state. If a parent moves and stops paying, the custodial parent can file in their home state, and that state can pursue enforcement across state lines, including wage garnishment from an out-of-state employer.

Can child support be waived or forgiven?

Parents cannot straightforward agree to cancel child support on their own. A court must approve any modification or waiver. Even if both parents agree to stop support, a judge may refuse if it appears the child's welfare would be harmed. Child support is considered the child's right, not a debt between parents.

What happens if the paying parent cannot afford the amount ordered?

If income drops due to job loss, illness, or other hardship, the paying parent should file a motion to modify rather than straightforward stop paying. A judge may lower the amount temporarily or permanently depending on the circumstances. Continuing to pay what was ordered, even if it causes hardship, is safer than risking contempt charges.

Are there federal limits on how much child support can be?

No. Federal law sets minimum standards but does not cap how much a state can order. States set their own maximum income levels for the guideline calculation. Some states have no cap at all, meaning a very high earner could owe substantially more than the guideline amount if a judge decides it is appropriate.