Estimate child support payments for all 50 states. Uses income shares, percentage of income, and Melson Formula models with custody adjustments, health insurance, and childcare add-ons.
Important Disclaimer
These calculators provide estimates for educational purposes only. Child support and family law calculations vary significantly by state, judge, and individual circumstances. Results are not legal advice and do not create an attorney-client relationship. Consult a licensed family law attorney in your state for advice specific to your situation.
Child support calculations in the United States follow three primary models, with the specific formula depending on your state. Understanding which model applies to your situation is the foundation of any child support estimate.
The Income Shares Modelis the most common, used by approximately 38 states. It begins by combining both parents' gross monthly incomes to determine total household resources, then looks up a basic support amount from published guidelines tables. Each parent's share is determined by their proportional contribution to combined income — the parent with primary custody provides their share through direct care, while the non-custodial parent makes payments. Health insurance premiums for the children and work-related childcare costs are added to the basic support as mandatory add-ons.
The Percentage of Income Model, used by Texas, Alaska, Mississippi, Wisconsin, and Nevada, calculates support as a fixed percentage of the paying parent's income only. Texas, the most-searched state for child support, applies 20% for 1 child, 25% for 2, 30% for 3, 35% for 4, and 40% for 5+ children of the paying parent's net monthly income, capped at $9,200 in net monthly resources.
The Melson Formula, used by Delaware, Hawaii, and Montana, is the most complex approach. It first establishes a self-support reserve — a minimum income the court leaves each parent to meet their own basic needs. After that, primary support amounts are calculated for the children, and any remaining income is distributed proportionally to improve the children's standard of living.
Alex earns $5,500/month gross income and Jordan earns $3,200/month. They have 2 children and live in Arizona (Income Shares state). Alex has primary custody; Jordan has standard visitation (every other weekend, approximately 73 overnights per year). Jordan pays $200/month for the children's health insurance; childcare costs $600/month.
This estimate would change significantly if Jordan had more parenting time. At 120 overnights per year (about 33%), an adjustment of approximately 12% would reduce the base obligation by roughly $96/month. At 50/50 shared custody, the calculation uses an offset method that would substantially reduce the payment. The numbers above are illustrative — Arizona courts use the official Child Support Guidelines Worksheet with actual income documents.
Combined Parental Income
In Income Shares states, both parents' incomes directly drive the support calculation. A significant income difference between parents means the lower-earning parent pays a smaller share. In Percentage of Income states, only the paying parent's income matters for the base calculation. Judges have discretion to impute income to a parent who is voluntarily underemployed — so quitting a job to reduce child support obligations rarely works as planned.
Custody and Parenting Time
The number of overnight stays the paying parent has with the children directly affects support in most states. Most states provide no adjustment for fewer than 91 overnights per year (standard visitation). Between 91-182 overnights, support typically reduces by 10-15%. At 183+ overnights (shared custody), most states apply a more significant reduction, often using an offset calculation rather than a simple adjustment.
Health Insurance and Childcare Costs
Health insurance premiums for the children and work-related childcare costs are mandatory add-ons to basic child support in almost every state. The parent who pays these costs gets credit — or the other parent is required to reimburse their proportional share. These add-ons can significantly increase the total support obligation, particularly in high-cost areas where childcare exceeds $1,500/month.
Number of Children and Other Support Obligations
Support increases with each additional child, though not proportionally — guidelines reflect economies of scale in child-rearing. A parent who is already paying child support for children from another relationship typically receives credit for those existing obligations, reducing the income available for subsequent support calculations. This prevents a situation where support obligations exceed what a parent can reasonably pay.
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Child support is calculated using one of three models depending on your state. Most states (38+) use the Income Shares Model, which combines both parents' incomes and calculates each parent's proportional share of the total support needed. A smaller number of states use the Percentage of Income Model, which bases support on a percentage of the paying parent's income alone — Texas (20-40%), Alaska, Mississippi, and Wisconsin use this approach. Delaware, Hawaii, and Montana use the more complex Melson Formula, which first sets aside a self-support reserve for each parent. Select your state in the calculator above to see which model applies to you.
The income used for child support calculations depends on your state's model. Income Shares states typically use gross income (before taxes) for both parents. Percentage of Income states like Texas use net income (after federal and state taxes). Some states like Connecticut and Pennsylvania calculate on net weekly income. In all states, courts may impute income — meaning if a parent is voluntarily unemployed or underemployed, the court can calculate support based on what they could earn at their actual earning capacity. Self-employment income, bonuses, rental income, and other earnings beyond a regular paycheck typically count as income for child support purposes.
Not necessarily. In most states, shared or equal custody (50/50) reduces child support significantly but does not eliminate it unless both parents have nearly identical incomes. When custody is equal, most states use an offset method: each parent's support obligation is calculated separately, and the higher earner pays the difference to the lower earner. This reflects the reality that children need consistent resources in both households. If incomes are very close, the resulting payment may be minimal — but true zero-support 50/50 arrangements are rare and require agreement by both parents, usually approved by the court.
Child support generally continues until the child reaches the age of majority (18 in most states, 19 in Alabama, Indiana, and Nebraska, 21 in Mississippi and sometimes Massachusetts) or graduates from high school — whichever occurs later up to the state maximum. Some states allow courts to order post-secondary education support for college expenses in certain circumstances. Child support does NOT end automatically when a child turns 18 — the paying parent must formally file for termination with the court. If a paying parent simply stops paying without a court order, they can accumulate significant arrears (back-owed support) even after the child is an adult.
Failure to pay court-ordered child support has serious consequences. States have extensive enforcement tools including wage garnishment (automatic income withholding), seizure of tax refunds and bank accounts, suspension of driver's and professional licenses, denial of passport applications, reporting to credit bureaus, contempt of court charges, and in serious cases, jail time. The federal government also participates in child support enforcement through programs including the Federal Parent Locator Service. If you are owed unpaid child support, contact your state's child support enforcement agency — this service is free. Back-owed support (arrears) accumulates interest in most states and does not expire.
Select your state for a child support calculator pre-set with your state's specific formula, guidelines, and rules.