New Hampshire Child Support Calculator
Uses NH Income Shares model — RSA 458-C with self-support reserve
Table of Contents
How New Hampshire Calculates Child Support
New Hampshire uses the Income Shares model under RSA 458-C (Revised Statutes Annotated). This law establishes comprehensive guidelines for calculating child support based on both parents' financial contributions. The NH approach is notable for including a self-support reserve, which ensures that the paying parent retains enough income to meet their own basic needs, preventing the support obligation from pushing them into poverty.
The calculation begins by determining each parent's adjusted gross income. Both adjusted incomes are combined and cross-referenced against the RSA 458-C support schedule to find the basic child support obligation. Each parent's share is proportional to their percentage of the combined income. Additional costs for health insurance, childcare, and extraordinary medical expenses are allocated between the parents in the same proportions.
New Hampshire's guidelines create a rebuttable presumption that the calculated amount is correct. Courts can deviate when the guidelines would produce an unjust or inappropriate result, but must make written findings explaining the deviation. The NH Department of Health and Human Services, Division of Child Support Services, administers enforcement and provides resources for parents navigating the system.
The Self-Support Reserve
One of the most distinctive features of New Hampshire's child support guidelines is the self-support reserve. Under RSA 458-C, the guidelines ensure that after paying child support, the obligor parent retains at least 115% of the federal poverty level for a single individual. This reserve recognizes that a parent who cannot meet their own basic needs will be unable to maintain employment and pay support consistently over time.
If applying the standard guideline calculation would reduce the obligor's income below the self-support reserve, the court adjusts the support amount downward. This does not eliminate the support obligation entirely but ensures a balance between the children's needs and the parent's ability to survive financially. The self-support reserve is adjusted periodically as the federal poverty guidelines are updated.
Income Definitions Under RSA 458-C
New Hampshire defines gross income broadly for child support purposes, including all earned and unearned income:
- Wages, salaries, tips, and overtime from all employment
- Commissions, bonuses, and incentive pay
- Self-employment income after legitimate business deductions
- Rental and property income
- Interest, dividends, and capital gains
- Pensions, retirement, and annuity income
- Social Security benefits (retirement, disability, survivor)
- Workers' compensation and disability benefits
- Unemployment insurance benefits
- Alimony received from another relationship
- Trust income and distributions
- Military pay including all allowances
- Prizes, awards, and gambling winnings
Allowable deductions from gross income include federal and state income taxes, FICA contributions, mandatory retirement contributions, union dues, alimony paid, and pre-existing child support obligations for other children.
Shared Custody and Parenting Time
New Hampshire addresses shared custody situations where both parents have significant parenting time. When custody is approximately equal (50/50 or near-equal), the court may apply a cross-credit calculation where each parent's obligation is computed separately and the obligations are offset. The parent with the higher income pays the difference to the lower-income parent.
For parenting arrangements that are not 50/50 but still involve significant time with the non-custodial parent, New Hampshire courts may adjust the support amount to reflect the direct costs borne by the non-custodial parent during their parenting time. This adjustment is not automatic and typically requires the parent to demonstrate the additional expenses they incur.
Modification and Enforcement
New Hampshire allows modification when there has been a substantial change in circumstances. Common grounds include changes in income, employment status, custody arrangements, health insurance costs, and the child's needs. Either parent can petition the court for review. The NH Division of Child Support Services also conducts periodic reviews of orders in Title IV-D cases.
Enforcement tools include income withholding, tax refund interception, license suspension (driver's, professional, recreational), contempt proceedings, property liens, bank account seizure, credit reporting, and passport denial. New Hampshire participates in UIFSA for interstate enforcement and the Federal Parent Locator Service.
New Hampshire Child Support and Taxes
New Hampshire has no state income tax on wages and salaries (though it taxes interest and dividends), which simplifies income calculations for many parents. Child support is neither taxable to the recipient nor deductible by the payer under federal law. Standard tax considerations for dependency exemptions, child tax credits, and filing status apply.
NH applies a self-support reserve ensuring each parent retains minimum income for basic needs before calculating support
New Hampshire Child Support Schedule
Below is a representative sample of the New Hampshire child support schedule showing basic monthly obligations:
| Combined Monthly Income | 1 Child | 2 Children | 3 Children | 4 Children | 5 Children |
|---|---|---|---|---|---|
| $1,500 | $273 | $410 | $470 | $508 | $542 |
| $2,500 | $400 | $602 | $689 | $746 | $795 |
| $3,500 | $497 | $747 | $846 | $920 | $986 |
| $5,000 | $625 | $938 | $1,060 | $1,156 | $1,239 |
| $7,500 | $817 | $1,218 | $1,365 | $1,497 | $1,610 |
| $10,000 | $990 | $1,468 | $1,643 | $1,805 | $1,943 |
| $15,000 | $1,285 | $1,895 | $2,127 | $2,341 | $2,525 |
| $20,000 | $1,530 | $2,228 | $2,510 | $2,768 | $2,990 |
New Hampshire RSA 458-C Guidelines Explained
New Hampshire's child support guidelines are established under RSA 458-C, which provides a comprehensive framework for calculating child support using the Income Shares model. The statute was last significantly updated to better reflect modern economic data on the cost of raising children in New Hampshire.
The NH Calculation Formula
New Hampshire's formula considers both parents' adjusted gross income, combines them, and uses a guideline table to determine the minimum support amount. Each parent's obligation is proportional to their share of the combined income. The guidelines create a rebuttable presumption — meaning the calculated amount is presumed correct unless a party demonstrates that deviation is warranted.
Net Income Definition Under RSA 458-C:2
NH defines gross income broadly to include wages, self-employment income, rental income, investment income, pensions, Social Security, unemployment compensation, workers' compensation, disability benefits, and alimony received. Allowable deductions include federal and NH taxes (NH has no broad income tax but taxes interest and dividends), FICA, mandatory retirement contributions, mandatory union dues, health insurance premiums for the child, and pre-existing child support obligations.
Self-Employment Income in NH Child Support
Self-employment income receives special treatment under New Hampshire child support guidelines. Self-employed parents must report their income accurately, and courts scrutinize business expenses to prevent income manipulation.
How NH Handles Self-Employment
- Gross receipts minus legitimate business expenses determine self-employment income
- Depreciation and home office deductions may be added back if they reduce income artificially
- Personal expenses run through the business (vehicle, phone, travel) are added back to income
- Retained earnings in closely-held corporations may be attributed as income to an owner-parent
- Average of 2-3 years of income is typically used for seasonal or variable self-employment
NH courts can appoint forensic accountants to evaluate self-employment income when one parent disputes the reported figures. The cost of the forensic review may be allocated between the parties.
Deviations from NH Guidelines
Under RSA 458-C:5, New Hampshire courts may deviate from the guideline amount when application would be unjust or inappropriate. Factors the court considers include:
- Extraordinary medical, dental, or educational expenses
- Significantly higher or lower living costs in the parent's community
- The child's special needs or talents requiring additional financial support
- Income of a parent's current spouse or partner (considered indirectly)
- Tax consequences to either parent
- Substantial travel costs for parenting time
- Combined income above the schedule maximum
- Seasonal or variable income patterns
How to Modify Child Support in New Hampshire
NH allows modification when there has been a substantial change in circumstances that is not temporary. Common grounds include:
- Change in either parent's income of 20% or more
- Change in custody or parenting time arrangement
- A child reaching emancipation age or becoming self-supporting
- Change in health insurance or childcare costs
- Disability or serious illness of either parent
File a motion to modify with the NH Family Division of the Circuit Court. Modifications are effective from the filing date. NH conducts automatic reviews of child support orders managed by the Division of Child Support Services every three years upon request.
Enforcement of NH Child Support
New Hampshire enforces child support through the Division of Child Support Services within the Department of Health and Human Services.
- Income withholding — standard for all orders
- Tax refund interception — federal and state
- License suspension — driver's, professional, recreational
- Contempt of court — fines and imprisonment for willful non-payment
- Property liens and bank account seizure
- Credit bureau reporting
- Passport denial for arrearages over $2,500
NH child support continues until the child reaches age 18, or through high school graduation if under age 19. For disabled adult children unable to support themselves, the court may extend support obligations.