Child Support by State — Complete US Guide
How all 50 states + DC calculate and enforce child support in 2026 — formula type (Income Shares vs Percentage vs Melson), termination age, college/post-secondary support availability, and guidelines review cycles.
What is child support law in the US?
Child support is state law with a mandatory federal framework. Every US state must have child support guidelines that produce a rebuttable presumptive amount (federal Title IV-D requirement, dating to 1988 amendments to the Family Support Act). Every state must review its guidelines at least every four years. But the specific formulas, termination ages, college support rules, and enforcement mechanisms vary substantially.
The three main guideline formula types are: Income Shares (most states — combines both parents' incomes and allocates support based on shared responsibility for the child), Percentage of Income (Texas, Wisconsin, Mississippi, North Dakota, Alaska, and New York use variants — flat percentage of noncustodial parent's income), and Melson formula (Delaware, Hawaii, Montana — self-support reserve first, then percentage of remainder). New York and DC use variants that produce among the highest support amounts.
How state child support laws vary
- Formula type: Income Shares (40+ states), Percentage of Income (6 states), Melson formula (3 states). Each produces different amounts for the same income scenarios.
- Termination age: Ranges from 18 (majority in most states) to 21 (Mississippi, DC, New York). Many states extend to 19 for high-school completion. Some extend for post-secondary education.
- College support: About a dozen states permit courts to order post-secondary educational support after majority — including New Jersey (Newburgh v. Arribas), New York, Massachusetts, Missouri, Illinois, Iowa, Oregon, Washington, DC, and Indiana. Pennsylvania rejected this in 1995 (Blue v. Blue)."},
- High-income cap: Some states cap guidelines application at high income; others require case-specific analysis above the cap.
- Imputation: When a parent is voluntarily unemployed or underemployed, states vary on whether and how to impute income for support calculation.
- Enforcement mechanisms: Federally-required tools include wage withholding, tax refund interception, license suspension, credit reporting, and passport denial. State-level variations add additional tools."
Federal framework for state child support
Federal law requires and structures state child support systems. Every state's IV-D program receives federal funding and must comply with federal requirements.
- Title IV-D of the Social Security ActFederal framework requiring every state to operate a child support enforcement program. Provides federal matching funds and mandatory enforcement mechanisms.
- Federal Guidelines Requirement (42 U.S.C. § 667)Every state must have child support guidelines producing a rebuttable presumptive amount and must review guidelines at least every four years.
- Uniform Interstate Family Support Act (UIFSA)Adopted by all 50 states + DC. Governs child support orders across state lines — one order controls, all states enforce.
- Federal Bradley Amendment (42 U.S.C. § 666(a)(9))Prohibits retroactive modification of child support arrears. Support obligations accrue as a matter of law and cannot be forgiven retroactively.
- Federal enforcement toolsFederal tax refund interception (FIDM), passport denial for arrears over $2,500, credit bureau reporting, and Federal Parent Locator Service.
Child Support in all 51 US jurisdictions
Grouped by region. Type any state name to filter. Published state guides open the full topic page; others link to the state hub.
Northeast
9 jurisdictions- FormulaIncome Shares
- Termination18 (19 HS)
- College supportYes (Ct. discretion)
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares (M.G.L. c. 208)
- Termination18 (23 if college)
- College supportYes (up to 23)
- Review4-year
- FormulaIncome Shares
- Termination18 (HS grad)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination19 (23 if college)
- College supportYes (Newburgh)
- Review4-year
- FormulaPercentage of Income (CSSA)
- Termination21
- College supportYes (statutory)
- Review4-year
- FormulaIncome Shares
- Termination18 (HS grad)
- College supportNo (post-Blue)
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
Midwest
12 jurisdictions- FormulaIncome Shares (2017)
- Termination18 (19 HS)
- College supportYes (educational)
- Review4-year
- FormulaIncome Shares
- Termination19
- College supportYes (educational)
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportYes (post-secondary)
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19½ HS)
- College supportNo
- Review4-year
- FormulaIncome Shares (2007)
- Termination18 (20 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (21 or 22 college)
- College supportYes (post-secondary)
- Review4-year
- FormulaIncome Shares
- Termination19
- College supportNo
- Review4-year
- FormulaPercentage of Income
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares (2019 refresh)
- Termination18 (19 HS)
- College supportYes (discretionary)
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaPercentage of Income
- Termination18 (19 HS)
- College supportNo
- Review4-year
South
17 jurisdictions- FormulaIncome Shares
- Termination19 (age of majority)
- College supportNo (post-Bayliss)
- Review4-year
- FormulaIncome Shares (2020)
- Termination18 (HS grad)
- College supportNo
- Review4-year
- FormulaMelson formula
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination21
- College supportYes
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (20 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaPercentage of Income
- Termination21
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (20 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (20 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportYes (Risinger factors)
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaPercentage of Income
- Termination18 (HS grad)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (20 HS)
- College supportNo
- Review4-year
West
13 jurisdictions- FormulaPercentage of Income
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares (Guideline)
- Termination18 (19 HS)
- College supportNo (limited)
- Review4-year
- FormulaIncome Shares
- Termination19
- College supportYes (post-secondary)
- Review4-year
- FormulaMelson formula
- Termination18 (19 HS)
- College supportYes (limited)
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaMelson formula
- Termination18 (19 HS)
- College supportYes (post-secondary)
- Review4-year
- FormulaPercentage of Income (2020 → Guideline)
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (19 HS)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (21 educational)
- College supportYes (educational)
- Review4-year
- FormulaIncome Shares
- Termination18 (HS grad)
- College supportNo
- Review4-year
- FormulaIncome Shares
- Termination18 (post-secondary Ct. discretion)
- College supportYes (discretionary)
- Review4-year
- FormulaIncome Shares
- Termination18 (20 HS)
- College supportNo
- Review4-year
Common child support issues (all states)
The problems that recur across every state. State-specific answers are on each state's dedicated child support guide.
Calculating the guideline amount
Each state's calculator combines gross income, allowable deductions, health insurance premiums, work-related childcare, and parenting-time credits (varies by state) to produce a presumptive support amount. Deviation from guidelines requires specific findings.
Modification when circumstances change
Support orders can be modified when circumstances substantially change (typically 15%+ change in support amount under guidelines). Voluntary income reduction generally doesn't qualify. Federal Bradley Amendment prohibits retroactive forgiveness of accrued arrears.
Interstate enforcement (UIFSA)
When one parent lives in a different state than the order, UIFSA controls. One state has 'continuing exclusive jurisdiction' to modify; other states must enforce. Federal Full Faith and Credit for Child Support Orders Act reinforces enforcement.
College and post-secondary support
About a dozen states permit courts to order college support after majority. Available in New Jersey, New York, Massachusetts, Missouri, Illinois, Iowa, Oregon, Washington, DC, Indiana. Rejected in Pennsylvania (Blue v. Blue). Support cap and duration vary.
Income imputation
When a parent is voluntarily unemployed or underemployed, most states can impute income based on earning capacity. Standards vary — some require bad faith; others use ability-based analysis. Custodial and noncustodial parents can both face imputation.
Support enforcement remedies
Federal-mandated tools include wage withholding (immediate income assignment), tax refund interception, credit bureau reporting, driver's license suspension, professional license suspension, passport denial (arrears over $2,500), and contempt proceedings including jail.
Frequently asked questions
The most common questions about child support across US states.
Recent child support law changes
The most notable state legal changes affecting child support in the last 90 days.
State Child Support Guidelines Review Cycle — 2026 Status
Federal 4-year review cycle status by state. Which states are actively reviewing guidelines in 2026 and what changes are being proposed.
Read the update →New York CSSA Case Law Updates 2026
Recent decisions on cap application, add-ons, and self-support reserve under NY Child Support Standards Act.
Read the update →Illinois Refines Income Shares Formula
IL Department of Healthcare and Family Services announced 2026 guideline refinements. Impact on typical support calculations.
Read the update →Post-Secondary Educational Support Tracker — 2026
Which US states permit courts to order college/post-secondary support after majority. Current statutory and caselaw status.
Read the update →Ohio Child Support Guidelines 2026 Refresh Effective
OH's revised guidelines (per 4-year federal cycle) took effect. Chart changes, deviation factors, and add-ons.
Read the update →Federal Court Clarifies Bradley Amendment Scope
Recent federal decision on the limits of Bradley Amendment's prohibition on retroactive modification. Impact on state-level modification practice.
Read the update →Explore the other silos
51 US jurisdiction landing pages. Every state's full topic list, distinctive features, and neighbors. Start with your own state.
100 state-by-state rankings on family & personal and every other legal category. Interactive tables, transparent methodology.
Step-by-step how-to guides that cross state boundaries. Practical, state-by-state process detail.
Fresh law-change coverage across all 51 jurisdictions. Every Tuesday. Free.