How is child support calculated?

Child support is calculated using state-specific guidelines. Most states use the "income shares" model, which combines both parents' incomes and assigns each parent a proportional share of the total support obligation. Some states use a "percentage of income" model based solely on the non-custodial parent's income. Three states use the Melson Formula, which is similar to income shares but includes a self-support reserve. Factors include: number of children, custody arrangement, health insurance costs, childcare costs, and other children supported.

Can I get my child support reduced if I lose my job?

Yes. A significant change in income (typically 15-25% reduction) generally qualifies as a "substantial change in circumstances," which is the legal standard for modifying a child support order. You must file a motion with the court or contact your state child support agency. Important: the modification is NOT retroactive to when you lost your job — it only takes effect from the date you file. File immediately when your income drops.

What happens if I don't pay child support?

Consequences for non-payment include: wage garnishment (up to 50-65% of disposable income), tax refund interception, driver's license suspension, professional license suspension, passport denial (for arrears over $2,500), bank account levy, credit reporting, liens on property, and contempt of court (which can result in jail time). Child support debt cannot be discharged in bankruptcy.

How does shared custody affect child support?

Most states provide a credit or adjustment when the non-custodial parent has significant parenting time. The threshold varies by state (typically 90-128+ overnights per year). In a true 50/50 custody arrangement, the higher-earning parent usually still pays some support to equalize the children's standard of living in both homes. Some states use a specific shared-custody formula that reduces the obligation proportionally to parenting time.

Can child support be modified after a criminal conviction?

Yes. A criminal conviction that results in incarceration or significant income loss can be grounds for modification. Many states now recognize that incarceration is not "voluntary unemployment." However, you must proactively file for modification — the court will not automatically adjust your order. Contact your state child support agency or a legal aid attorney as soon as possible after conviction.

Is child support tax deductible?

No. Child support payments are not tax-deductible for the paying parent and are not considered taxable income for the receiving parent. This is different from alimony/spousal support, which had different tax treatment prior to 2019. However, if you owe arrears, the IRS can intercept your federal and state tax refunds through the Federal Tax Refund Offset Program.

Child Support Calculator — How Much Will I Pay or Receive?

Last updated: 2026-03-28

Child support is calculated differently in every state. Most states (38+) use the "income shares" model, which bases the obligation on both parents' combined income. About 10 states use a "percentage of income" model based only on the non-custodial parent's income. Three states (Delaware, Hawaii, Montana) use the Melson Formula, which factors in a poverty-level self-support reserve. Use the free calculator below to get an instant estimate for your state.

Child Support Estimator

Free, instant estimate for all 50 states + DC. No email required.

State *

Your role *

Your gross monthly income ($) *

Before taxes, all sources

Other parent's gross monthly income ($) *

Number of children *

Custody arrangement

Who provides children's health insurance?

Monthly childcare costs ($)

Daycare, after-school, etc.

Other children you support (from other relationships)

Currently incarcerated or recently released

This affects modification options and arrears. We'll show specific guidance.

The Three Child Support Models Explained

1. Income Shares Model (38+ states)

Used by the majority of states. Both parents' incomes are combined, and a guideline table determines the total child support obligation based on that combined income and the number of children. Each parent is then responsible for their proportional share. The custodial parent's share is presumed to be spent directly on the children through daily care.

States: AL, AZ, AR, CA, CO, CT, DC, FL, GA, ID, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MO, NE, NH, NJ, NM, NY, NC, OH, OK, OR, PA, RI, SC, SD, TN, UT, VT, VA, WA, WV

2. Percentage of Income Model (~10 states)

A simpler approach: a fixed percentage of the non-custodial parent's income is applied based on the number of children. The custodial parent's income is generally not considered in the base calculation (though it may factor into deviations). Texas is the most well-known percentage-of-income state.

States: AK, MS, NV, ND, TX, WI, WY

3. Melson Formula (3 states)

The most complex model. Similar to income shares, but with an additional step: each parent is first allowed to keep enough income to meet their own basic needs (a "self-support reserve" based on the federal poverty level). Only income above this reserve is used to calculate the child support obligation. This protects extremely low-income parents from having zero resources.

States: DE, HI, MT

Child Support Model by State

State	Model	1 Child	2 Children	3 Children
Alabama	Income Shares	17-23%	24-30%	27-35%
Alaska	Percentage	20-27%	27-33%	33-39%
Arizona	Income Shares	16-22%	23-30%	27-34%
California	Income Shares	18-25%	26-33%	30-38%
Colorado	Income Shares	16-22%	23-30%	27-34%
Delaware	Melson	17-22%	24-30%	28-35%
Florida	Income Shares	17-24%	24-31%	28-36%
Georgia	Income Shares	17-23%	24-30%	27-35%
Hawaii	Melson	18-24%	25-32%	29-37%
Illinois	Income Shares	17-22%	25-31%	29-36%
Mississippi	Percentage	14%	20%	22%
Montana	Melson	16-21%	23-29%	27-34%
Nevada	Percentage	18%	25%	29%
New York	Income Shares	17%	25%	29%
North Carolina	Income Shares	17-23%	24-31%	28-35%
Ohio	Income Shares	17-24%	24-31%	28-36%
Pennsylvania	Income Shares	17-24%	24-31%	28-36%
Texas	Percentage	20%	25%	30%
Virginia	Income Shares	17-24%	24-31%	28-36%
Washington	Income Shares	17-24%	24-31%	28-36%
Wisconsin	Percentage	17%	25%	29%

Percentages shown are approximate guideline ranges of combined income (income shares/Melson) or obligor income (percentage states). Actual amounts depend on specific income levels, deductions, and state guideline tables. Use the calculator above for a personalized estimate.

Incarceration & Child Support — What You Need to Know

Child support does NOT automatically stop when you go to jail or prison. Unless you take action to modify your order, the full amount continues to accrue as arrears. After years of incarceration, many people emerge with tens of thousands of dollars in child support debt.

The 2016 federal rule change was a game-changer.The "Flexibility, Efficiency, and Modernization" rule encouraged states to treat incarceration of 180+ days as a substantial change in circumstances and to stop imputing income to incarcerated parents. As of 2026, most states have adopted some version of this reform.

Steps if you are incarcerated or recently released:

Contact your state child support enforcement agency immediately
File a motion to modify your support order (you can do this from prison)
If recently released, file for modification based on your current income
Request a payment plan for any arrears
Contact LawHelp.org for free legal assistance

How to Modify a Child Support Order

When you can request modification

Job loss or significant income reduction (15-25%+ in most states)
Disability or serious health issue
Incarceration (180+ days in most states)
Change in custody arrangement
Child's needs change (medical, educational)
Other parent's income significantly increases
Periodic review (every 3 years in most states, upon request)

How to file

Contact your local child support agency (they can help for free)
File a "Motion to Modify" with the court that issued the original order
Provide documentation of your changed circumstances (pay stubs, termination letter, medical records, etc.)
Attend the hearing (or request a phone appearance if incarcerated/remote)
The court will review and issue a modified order if warranted

Critical: Modifications are NOT retroactive in most states. They typically take effect from the date you file the motion, not from when your circumstances changed. File as soon as possible.

Take Action — Direct Links

Find your state child support agency
Contact info for all 50 state agencies — file for modification, check balances, set up payments
LawHelp.org — Free legal aid by state
Find free legal assistance for child support modification, arrears negotiation, and custody matters
Companies that hire people with records
Find employment to meet your child support obligations — 200+ companies reviewed
Expunge your record — increase earning potential
Check eligibility for expungement in your state to improve job prospects and income
NCSL — Child support models by state
Official state-by-state breakdown of which guideline model each state uses

Frequently Asked Questions

How is child support calculated?: Child support is calculated using state-specific guidelines. Most states use the "income shares" model, which combines both parents' incomes and assigns each parent a proportional share of the total support obligation. Some states use a "percentage of income" model based solely on the non-custodial parent's income. Three states use the Melson Formula, which is similar to income shares but includes a self-support reserve. Factors include: number of children, custody arrangement, health insurance costs, childcare costs, and other children supported.
Does child support stop if I go to jail or prison?: No. In most states, child support obligations continue to accrue during incarceration. Arrears (back-owed support) build up the entire time. However, following a 2016 federal rule change, many states now treat incarceration of 180+ days as a "substantial change in circumstances" that allows you to petition for modification. Some states even prohibit treating incarceration as "voluntary unemployment." It is critical to file for modification as soon as possible — support won't be reduced retroactively.
Can I get my child support reduced if I lose my job?: Yes. A significant change in income (typically 15-25% reduction) generally qualifies as a "substantial change in circumstances," which is the legal standard for modifying a child support order. You must file a motion with the court or contact your state child support agency. Important: the modification is NOT retroactive to when you lost your job — it only takes effect from the date you file. File immediately when your income drops.
What happens if I don't pay child support?: Consequences for non-payment include: wage garnishment (up to 50-65% of disposable income), tax refund interception, driver's license suspension, professional license suspension, passport denial (for arrears over $2,500), bank account levy, credit reporting, liens on property, and contempt of court (which can result in jail time). Child support debt cannot be discharged in bankruptcy.
How does shared custody affect child support?: Most states provide a credit or adjustment when the non-custodial parent has significant parenting time. The threshold varies by state (typically 90-128+ overnights per year). In a true 50/50 custody arrangement, the higher-earning parent usually still pays some support to equalize the children's standard of living in both homes. Some states use a specific shared-custody formula that reduces the obligation proportionally to parenting time.
Can child support be modified after a criminal conviction?: Yes. A criminal conviction that results in incarceration or significant income loss can be grounds for modification. Many states now recognize that incarceration is not "voluntary unemployment." However, you must proactively file for modification — the court will not automatically adjust your order. Contact your state child support agency or a legal aid attorney as soon as possible after conviction.
Is child support tax deductible?: No. Child support payments are not tax-deductible for the paying parent and are not considered taxable income for the receiving parent. This is different from alimony/spousal support, which had different tax treatment prior to 2019. However, if you owe arrears, the IRS can intercept your federal and state tax refunds through the Federal Tax Refund Offset Program.

Disclaimer:This calculator provides simplified estimates for informational purposes only. It is NOT legal advice and does NOT replace your state's official child support guidelines or calculator. Actual child support amounts are determined by courts using detailed state-specific formulas, tax considerations, and judicial discretion. Many factors not captured here (mandatory retirement contributions, union dues, special needs, travel costs, etc.) can significantly affect the final amount. Consult a family law attorney or your state child support agency for accurate calculations. If you are incarcerated, contact legal aid immediately — LawHelp.org.