Complete Guide to Child Support

Everything you need to know about child support in the United States -- from how payments are calculated to how orders are enforced. This guide covers all 50 states and explains the differences between state models in plain language.

What Is Child Support?

Child support is a court-ordered financial obligation paid by the noncustodial parent (or the higher-earning parent in shared custody arrangements) to help cover the costs of raising a child. The purpose of child support is to ensure that children maintain a standard of living reasonably consistent with what they would have experienced if the parents had remained together.

Every state has child support guidelines established by statute or court rule. These guidelines create a presumptive amount based on objective factors -- primarily the parents' incomes and the amount of time the child spends with each parent. Courts can deviate from the guidelines in unusual circumstances, but the guideline amount is the starting point in virtually every case.

Child support is a right of the child, not the parent. This means parents cannot waive child support in a divorce agreement, and courts will not approve settlements that leave children without adequate financial support. It also means that child support obligations survive bankruptcy -- they cannot be discharged.

How Is Child Support Calculated?

The United States uses three main models for calculating child support. Each state has adopted one of these models, though many states have customized the formulas with their own adjustments, caps, and deductions.

Income Shares Model (41 States)

The income shares model is used by the majority of states. The fundamental principle is that the child should receive the same proportion of parental income that they would have received if the parents lived together. The calculation works as follows:

1. Determine each parent's gross (or net, depending on the state) income
2. Combine both parents' incomes
3. Look up the basic child support obligation on the state's schedule table based on combined income and number of children
4. Prorate the obligation between parents based on their share of combined income
5. Apply adjustments for healthcare premiums, childcare costs, and extraordinary expenses
6. Apply parenting time adjustments (overnights) if applicable

States using this model include California, Florida, Georgia, Illinois, Michigan, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Texas (hybrid), Virginia, and Washington, among many others.

Percentage of Income Model (6 States)

The percentage of income model is simpler. It applies a flat or varying percentage to the noncustodial parent's income based on the number of children. For example, Wisconsin uses 17% for one child, 25% for two, 29% for three, 31% for four, and 34% for five or more.

States using a pure or modified percentage of income model include Mississippi, Nevada, North Dakota, Texas, and Wisconsin. This model does not consider the custodial parent's income, which critics argue can lead to inequitable results when the custodial parent earns significantly more.

Melson Formula (3 States)

The Melson formula, used by Delaware, Hawaii, and Montana, is the most complex model. It builds on the income shares approach but adds a self-support reserve for each parent (ensuring neither falls below a poverty-level standard of living) and a standard of living adjustment that shares additional income with the child above the basic obligation.

What Income Is Included?

Most states define income broadly for child support purposes. Included income typically encompasses:

• Wages, salaries, and tips
• Overtime, bonuses, and commissions
• Self-employment income (gross receipts minus ordinary and necessary business expenses)
• Rental and investment income (dividends, interest, capital gains)
• Pension and retirement distributions
• Social Security benefits (including disability)
• Workers' compensation and unemployment benefits
• Alimony received from other relationships
• Trust income and annuities
• Military pay (including allowances)

Common deductions allowed before calculating the child support obligation include federal and state income taxes, FICA/Social Security taxes, mandatory retirement contributions, union dues, existing child support obligations for other children, and health insurance premiums for the child.

How Custody Time Affects Child Support

Custody time, typically measured in overnights per year, is one of the most significant factors in child support calculations. The logic is straightforward: the more time a child spends with a parent, the more that parent spends directly on the child's food, housing, transportation, and activities.

Most states using the income shares model include an overnight adjustment. When the noncustodial parent's overnights exceed a threshold (commonly 92 to 128 nights per year, or roughly 25-35% of the time), the child support obligation is reduced. States like Colorado, Indiana, and Virginia use a sliding scale where the reduction increases proportionally with overnights.

In a true 50/50 custody arrangement (182.5 overnights each), the child support obligation is typically much smaller and flows from the higher-earning parent to the lower-earning parent. In some states, if incomes are roughly equal and custody is 50/50, the support obligation may be zero.

Duration: How Long Does Child Support Last?

In most states, child support continues until the child reaches the age of majority, which is 18 in most jurisdictions. However, there are important exceptions and extensions:

• High school completion: Many states extend support until the child graduates from high school, even if that occurs after age 18, typically capped at age 19 or 20.
• College: A handful of states (including New York, which may require support until 21, and states like Indiana, Iowa, Missouri, and New Hampshire) can order parents to contribute to college expenses.
• Disability: If a child has a disability that prevents self-support, child support may continue indefinitely.
• Emancipation: Support ends if the child marries, joins the military, or is legally emancipated before the age of majority.

Modifying Child Support

Child support orders are not permanent -- they can be modified when there is a substantial change in circumstances. Common grounds for modification include:

• A significant change in either parent's income (typically 15-25% or more)
• A change in the custody arrangement or parenting time
• A change in the child's needs (medical, educational, or special needs)
• Changes in healthcare or childcare costs
• A parent becoming involuntarily unemployed or disabled
• A new child born to either parent

To modify child support, you must file a motion with the court that issued the original order. Most states also allow modifications through the state child support enforcement agency. It is critical to file promptly -- in most states, modifications can only be applied going forward from the date of filing, not retroactively.

Enforcement: What Happens If Child Support Is Not Paid?

Child support enforcement is taken seriously by every state. The consequences of nonpayment can be severe:

• Wage garnishment: Employers can be ordered to withhold child support directly from the paying parent's paycheck. Income withholding is automatic for most new and modified orders.
• Tax refund interception: State and federal tax refunds can be intercepted to pay child support arrears.
• License suspension: Driver's licenses, professional licenses, and recreational licenses can be suspended for nonpayment.
• Credit reporting: Unpaid child support is reported to credit bureaus, damaging the parent's credit score.
• Bank account seizure: Courts can order banks to freeze and seize funds from the parent's accounts.
• Property liens: Liens can be placed on real estate and other property.
• Passport denial: The federal government will deny or revoke passports for parents owing more than $2,500 in arrears.
• Contempt of court: Willful nonpayment can result in fines and jail time.

Interest accrues on unpaid arrears in most states, typically at rates ranging from 6% to 12% per year. Arrears survive bankruptcy and can be enforced until fully paid, even after the child reaches adulthood.

Self-Employment and Imputed Income

Self-employment complicates child support calculations because self-employed parents have more control over their reported income. Courts scrutinize self-employment income carefully, looking at gross receipts, business expenses (distinguishing between legitimate expenses and personal spending run through the business), depreciation add-backs, and lifestyle analysis.

If a court finds that a parent is voluntarily unemployed or underemployed -- that is, deliberately reducing their income to lower their child support obligation -- the court can impute income. Imputed income is the amount the parent could reasonably be expected to earn based on their education, work history, skills, job market, and prior earning history.

Tax Implications of Child Support

Under current federal tax law (the Tax Cuts and Jobs Act of 2017), child support payments are neither tax-deductible for the paying parent nor taxable income for the receiving parent. This applies to all child support orders, regardless of when they were issued.

This is an important distinction from alimony, which had different tax treatment before 2019. Some parents mistakenly believe they can deduct child support payments -- they cannot. However, the parent with whom the child lives for more than half the year (the custodial parent) may claim the child as a dependent for tax purposes, including the child tax credit and head of household filing status. The custodial parent can sign IRS Form 8332 to release the dependency exemption to the noncustodial parent if both agree.

Child Support and Health Insurance

Most child support orders include a provision requiring one or both parents to provide health insurance for the child. Typically, the court orders the parent who can obtain coverage at the most reasonable cost (usually through an employer plan) to enroll the child. The cost of the child's health insurance premium is usually factored into the child support calculation.

Uninsured medical expenses (co-pays, deductibles, orthodontics, therapy, prescriptions) are generally split between parents in proportion to their incomes, though the specific split varies by state and court order.

Filing for Child Support

You can establish a child support order through the family court system or through your state's child support enforcement agency (often called the Office of Child Support Services or Division of Child Support Enforcement). The general process involves:

1. Filing a petition or application for child support
2. Establishing paternity (if the parents were not married) through voluntary acknowledgment or genetic testing
3. Providing financial documents (pay stubs, tax returns, bank statements)
4. Attending a hearing or administrative conference
5. Receiving a child support order from the court or agency

Many states now allow you to begin the process online. Child support services are available at no cost or low cost through state agencies, regardless of whether you have an attorney.

Frequently Asked Questions