Child Support Calculator

The Child Support Calculator helps you estimate monthly child support payments using the Income Shares Model, which is used by approximately 40 US states. This model considers both parents' incomes, the number of children, custody arrangements, and additional expenses like childcare and health insurance to determine a fair support obligation.

How Does the Income Shares Model Work?

The Income Shares Model is based on the principle that children should receive the same proportion of parental income as they would if the parents lived together. The calculation follows these steps:

1. Combined Income: Both parents' gross monthly incomes are added together
2. Base Obligation: A base child support amount is determined from a schedule based on combined income and number of children
3. Income Shares: The base obligation is divided proportionally based on each parent's percentage of the combined income
4. Custody Adjustment: A cross-credit adjustment is applied based on each parent's percentage of custody time
5. Additional Expenses: Childcare, health insurance, and extraordinary costs are added and shared proportionally

Understanding Custody and Its Impact on Support

Custody arrangement is one of the most significant factors in child support calculations. In general:

• Primary Custody (70-100%): The non-custodial parent typically pays the full calculated obligation
• Extended Visitation (60-70%): A moderate reduction may apply for the non-custodial parent
• Shared Custody (40-60%): Both parents bear direct costs during their time, significantly reducing the net payment

Use the Custody Sensitivity Chart in the results to see exactly how different custody arrangements affect the estimated payment.

What Expenses Are Included?

How to Use This Calculator

1. Enter incomes: Input each parent's gross monthly income (before taxes). Use pay stubs, tax returns, or employment records for accuracy.
2. Select children: Choose the number of children requiring support (1 to 6).
3. Set custody split: Enter Parent 1's percentage of custody time. The remaining percentage automatically applies to Parent 2.
4. Add expenses (optional): Include monthly childcare, health insurance, and extraordinary expenses for the children.
5. Review results: Analyze the estimated payment, calculation steps, income share breakdown, and custody sensitivity chart.

Important Considerations

• This calculator provides estimates only. Actual child support orders are determined by state courts using state-specific guidelines.
• Gross income typically includes wages, salaries, commissions, bonuses, overtime, self-employment income, and investment income.
• Some states use net income (after taxes) instead of gross income. Adjust accordingly if your state uses net income.
• Courts may deviate from guidelines based on special circumstances (high income, special needs children, travel costs).
• Child support is generally not tax-deductible for the payer and not taxable income for the recipient under US federal law (IRS Publication 504). The 2017 tax law changed this only for alimony.

Frequently Asked Questions

How is child support calculated in the US?

Most US states use the Income Shares Model, which calculates a base obligation from both parents' combined income and divides it proportionally based on each parent's income share. The model is adjusted for custody time, childcare costs, and health insurance premiums.

Does custody percentage affect child support?

Yes, significantly. The more time the non-custodial parent spends with the child (more overnights), the lower their child support obligation. In shared custody arrangements (close to 50/50), the payment amount is typically much smaller.

Is child support taxable?

No. Under US federal tax law, child support payments are not tax-deductible for the paying parent and are not taxable income for the receiving parent (IRS Publication 504). This has always been the case; the 2017 Tax Cuts and Jobs Act changed the rules for alimony, not child support.

What expenses are included in child support?

Child support typically covers basic needs like housing, food, and clothing. Additional items such as childcare, health insurance premiums for the children, and extraordinary expenses (private school, special medical needs) are often added to the base obligation and split proportionally.

Can child support be modified after it is set?

Yes. Child support orders can be modified if there is a significant change in circumstances such as job loss, significant income change, change in custody arrangement, or change in the child's needs. You typically need to petition the court for a modification.