Child Support Payment Calculator
Estimate monthly child support obligations using the Income Shares Model, the most widely adopted method across U.S. states. Results are estimates only — consult a family law attorney for legal advice.
Formula (Income Shares Model)
1. Combined Income = NCP Income + CP Income
2. NCP Income Share (%) = NCP Income ÷ Combined Income
3. Basic Support Obligation (BSO) = Combined Income × Child % Schedule
Child % Schedule: 1 child=17%, 2=25%, 3=29%, 4=31%, 5=32%, 6+=35%
4. NCP Share of BSO = BSO × NCP Income Share %
5. Add-ons = NCP Healthcare + NCP Childcare Contributions
6. Parenting Time Adjustment (if NCP > 92 nights/year):
Adjustment = (Nights/365 − 0.25) × 2 × NCP BSO (capped at 50%)
7. Final Payment = NCP BSO + Add-ons − Parenting Time Adjustment
If NCP income < $1,000/month → minimum order = 10% of NCP income
Assumptions & References
- Uses the Income Shares Model adopted by ~40 U.S. states (NCSL, 2024).
- Child percentage schedule is based on widely published state guidelines (e.g., Virginia, Colorado, Indiana).
- Parenting time adjustment threshold of 92 overnights/year (~25%) is the most common statutory trigger for shared-custody reduction.
- Self-support reserve of $1,000/month reflects typical state minimums to ensure NCP can meet basic needs.
- Gross income is used before taxes; some states use net income — consult your state's specific guidelines.
- Does not account for extraordinary expenses, prior support orders, or imputed income.
- This calculator provides estimates only. Actual orders are set by a court. Consult a licensed family law attorney.
- References: NCSL Child Support Guideline Models (2024); U.S. DHHS Office of Child Support Services.