Official RSA 458-C Sliding Scale Estimate
New Hampshire determines child support obligations using the Income Shares model as established in RSA 458-C. This model assumes that the child should receive the same proportion of parental income that they would have received if the parents lived together. The state applies a sliding scale percentage to the Combined Net Annual Income of both parents to determine the total support obligation.
Unlike many states, New Hampshire does not use a flat rate. The percentage of income allocated to support decreases as the parents' combined income increases. For example, for one child, the rate ranges from 25.6% at lower incomes down to 19% for high earners. The Department of Health and Human Services (DHHS) publishes an official table and requires interpolation for income levels between listed thresholds.
(Numbers below are illustrative only, based on current guidelines)
The New Hampshire self-support reserve is updated periodically to ensure the paying parent can maintain a basic standard of living. If an obligor's income is below the threshold, the court generally orders a minimum support amount of $50 per month.
New Hampshire uses "Net Monthly Income." This is total gross income minus federal taxes, social security, Medicare, and mandatory retirement contributions. Both parents' incomes are combined to determine the family's total resources.
New Hampshire law provides specific rebuttable presumptions for shared custody arrangements. If parents share "Equal or Approximately Equal" parenting time (40%+ each), the court may deviate from the standard guidelines to ensure both households can meet the child's needs.
Estimate only. This calculation is based on official RSA 458-C sliding scale tables and current statutory self-support reserves. For a binding order, consult NH DHHS or a family-law attorney.