New Hampshire calculates child support using the income shares model under RSA 458-C, which sets guideline percentages ranging from 25.6% of combined net income for one child (at income levels of $15,000 or less) down to 19% at income levels of $125,000 or more. The state provides a free online child support calculator through the Department of Health and Human Services at business.nh.gov, and New Hampshire courts presume the guideline amount is correct unless a party demonstrates special circumstances warranting deviation under RSA 458-C:5. The filing fee for a divorce involving minor children is $252 as of March 2026.
| Key Fact | Detail |
|---|---|
| Governing Statute | RSA Chapter 458-C |
| Calculation Model | Income Shares |
| Filing Fee (with children) | $252 |
| Filing Fee (without children) | $250 |
| Waiting Period | None (no statutory cooling-off period) |
| Residency Requirement | Both domiciled in NH: none; sole filer: 1 year |
| Grounds | No-fault (irreconcilable differences) or fault-based |
| Property Division | Equitable distribution |
| Guideline Percentage (1 child) | 25.6% at $15,000 or less combined net income |
| Official Calculator | NH DHHS online calculator at business.nh.gov |
How New Hampshire Calculates Child Support Under the Income Shares Model
New Hampshire determines child support obligations by combining both parents' net incomes and applying a statutory percentage from the guideline table published under RSA 458-C:3. For one child, the guideline percentage starts at 25.6% of combined net income when that income is $15,000 or less per year, then gradually decreases to 19% at combined net income of $125,000 or more. The resulting obligation is then divided between the parents in proportion to each parent's share of the combined income.
The income shares model reflects the principle that a child should receive the same proportion of parental income that the child would have received if both parents lived together. New Hampshire adopted this approach because research shows children's expenses correlate with household income levels. The child support calculator New Hampshire provides through DHHS automates this calculation, but understanding the underlying formula helps parents verify accuracy and prepare for court proceedings.
The guideline table published by the New Hampshire Department of Health and Human Services lists combined monthly adjusted gross income amounts in $10 increments. Each row includes the corresponding guideline amounts and percentages for one child, two children, three children, and four or more children. Courts treat the guideline amount as a rebuttable presumption, meaning the calculated figure applies unless a party proves deviation is warranted.
Guideline Percentages by Income Level and Number of Children
| Combined Net Income | 1 Child | 2 Children | 3 Children | 4+ Children |
|---|---|---|---|---|
| $15,000 or less | 25.6% | 35.5% | 40.2% | 43.6% |
| $25,000 | 25.0% | 34.6% | 39.2% | 42.5% |
| $35,000 | 24.0% | 33.3% | 37.6% | 40.8% |
| $50,000 | 23.0% | 31.9% | 36.1% | 39.2% |
| $75,000 | 21.5% | 29.8% | 33.7% | 36.6% |
| $100,000 | 20.0% | 27.7% | 31.4% | 34.0% |
| $125,000 or more | 19.0% | 26.3% | 29.8% | 32.3% |
What Counts as Income for the New Hampshire Child Support Worksheet
New Hampshire defines "adjusted gross income" under RSA 458-C:2 as all gross income from any source, reduced by five specific deductions: court-ordered support actually paid to others, 50% of actual self-employment tax paid, mandatory (not discretionary) retirement contributions, actual state income taxes paid, and amounts paid for allowable child care expenses or medical support for the children covered by the order. The child support worksheet New Hampshire courts require captures each of these deductions line by line.
Gross income includes wages, salaries, commissions, bonuses, dividends, pensions, interest, trust income, annuities, Social Security benefits, workers' compensation, unemployment insurance, disability insurance, veterans' benefits, and any other source of income. New Hampshire courts may also impute income to a parent who is voluntarily unemployed or underemployed, meaning the court assigns an earning capacity based on education, work history, and local job market conditions.
After calculating adjusted gross income, the formula subtracts standard deductions published annually by DHHS based on federal IRS withholding table amounts for federal income tax, FICA, and Medicare. The result is "net income" under RSA 458-C:2. Both parents' net incomes are combined, and the guideline percentage from the table under RSA 458-C:3 is applied to that combined figure.
Step-by-Step Guide to Using the Child Support Calculator New Hampshire Provides
The New Hampshire DHHS provides a free online child support calculator at business.nh.gov/dhhs_Calculator that generates an estimate based on current financial information. This child support estimator follows the same formula courts use under RSA 458-C:3, though the court's final order may differ based on special circumstances. Follow these steps to calculate child support in New Hampshire accurately.
- Gather both parents' financial documents including W-2s, tax returns, pay stubs, and records of all other income sources for the most recent 12-month period.
- Calculate each parent's gross income from all sources as defined in RSA 458-C:2, including wages, self-employment income, investment returns, and government benefits.
- Subtract the five allowable deductions from each parent's gross income: prior support orders, 50% of self-employment tax, mandatory retirement contributions, state income taxes, and qualifying child care or medical costs.
- Apply the standard deductions (federal income tax, FICA, and Medicare withholding based on IRS tables) to arrive at each parent's net income.
- Combine both parents' net incomes and locate the corresponding row in the guideline table under RSA 458-C:3.
- Multiply the combined net income by the guideline percentage for the applicable number of children.
- Divide the resulting obligation between the parents in proportion to each parent's percentage share of the combined net income.
- The parent with fewer parenting days (the obligor) pays their proportional share to the custodial parent (the obligee).
Sample Calculation
Consider two parents with a combined monthly net income of $6,000 ($72,000 annualized) and one child. The guideline table assigns approximately 21.5% for one child at the $75,000 income level. The monthly obligation would be approximately $6,000 multiplied by 21.5%, yielding roughly $1,290 per month. If Parent A earns 60% of the combined income and Parent B earns 40%, and Parent A is the noncustodial parent, Parent A would owe approximately $774 per month (60% of $1,290).
Adjustments and Deviations From the New Hampshire Child Support Guidelines
New Hampshire courts may deviate from the guideline amount when applying it would be unjust or inappropriate under RSA 458-C:5. The statute lists specific factors courts consider before ordering a deviation, including extraordinary medical expenses, extraordinary educational expenses, significantly higher or lower living costs, the economic consequences of the parenting schedule, the obligor's support of other dependents, and the child's independent financial resources.
A court deviating from the guidelines must make written findings explaining why the guideline amount is unjust and how the adjusted amount serves the child's best interests. In practice, New Hampshire judges deviate from guidelines in approximately 10-15% of cases, most commonly for shared parenting time adjustments or extraordinary expenses. The child support calculator New Hampshire offers through DHHS does not automatically account for deviations, so parents anticipating special circumstances should consult a family law attorney.
Parenting time adjustments represent the most common deviation factor in New Hampshire. When the noncustodial parent exercises parenting time exceeding the standard schedule, courts may reduce the support obligation to reflect the direct expenses that parent incurs during extended parenting time. New Hampshire does not use a specific overnight threshold formula like some states, but courts consider the actual division of parenting responsibilities when determining whether adjustment is warranted.
Health Insurance and Child Care Costs in the Support Calculation
New Hampshire requires both parents to contribute to the child's health insurance premium costs in proportion to their respective incomes under RSA 458-C:3, V. The parent who carries the health insurance policy may receive a credit against their child support obligation for the child's share of the premium. Courts calculate this credit by dividing the total policy premium by the number of people covered, then multiplying by the number of children on the order.
Child care expenses necessary for either parent's employment, job training, or education are included in the child support calculation. Under RSA 458-C:3, IV, reasonable child care costs are added to the base child support amount and allocated between the parents proportionally. The New Hampshire child support worksheet includes dedicated lines for both health insurance premiums and child care expenses, ensuring these costs are captured before the final obligation is determined.
Uninsured medical expenses (co-pays, deductibles, orthodontia, therapy, and prescriptions not covered by insurance) are typically divided between the parents in proportion to their incomes, though the court may order a different allocation. New Hampshire courts generally address uninsured medical expense allocation in the final divorce decree or parenting plan.
How to Modify a New Hampshire Child Support Order
Under RSA 458-C:7, either parent may petition the court to modify child support at any time by demonstrating a substantial change in circumstances, such as a job loss reducing income by 25% or more, a significant raise, the child's changed medical needs, or a material change in the parenting schedule. New Hampshire also permits automatic review without proving changed circumstances every 3 years after the last support order, which distinguishes New Hampshire from states requiring changed circumstances for any modification.
The 3-year automatic review provision under RSA 458-C:7 allows either parent or DHHS to recalculate support using current incomes and the current guideline table. If the recalculated amount differs materially from the existing order, the court may modify the obligation. This provision recognizes that children's needs and parents' financial circumstances naturally change over time.
To file a modification, a parent submits a motion to the Family Division of the Circuit Court in the county where the original order was issued. The filing fee for a modification petition is approximately $100-$125 as of March 2026. Verify the current fee with your local clerk of court. The modification takes effect from the date the motion is filed, not retroactively, so parents experiencing financial hardship should file promptly rather than waiting.
Enforcement of Child Support Orders in New Hampshire
New Hampshire enforces child support orders through DHHS Child Support Services and the courts, with enforcement tools including income withholding (wage garnishment), tax refund interception through the Federal Tax Refund Offset Program, suspension of driver's licenses and professional licenses under RSA 161-C:11, passport denial for arrears exceeding $2,500, liens on real and personal property, and contempt of court proceedings that can result in fines or imprisonment for up to 12 months.
Income withholding is the default enforcement mechanism in New Hampshire. Under federal law and RSA 458-B, all new child support orders include an automatic income withholding provision requiring the obligor's employer to deduct support payments directly from wages. The employer forwards payments to the NH State Disbursement Unit (SDU), which distributes funds to the custodial parent, typically within 2-3 business days of receipt.
New Hampshire reports child support arrears to all three major credit bureaus (Equifax, Experian, and TransUnion) when the arrearage exceeds $1,000, which can significantly impact the obligor's credit score. Parents who fall behind should contact DHHS Child Support Services at 1-800-852-3345 ext. 14427 to discuss payment plans or modification options before enforcement actions escalate.
Child Support Duration and Termination in New Hampshire
Child support in New Hampshire continues until the child reaches age 18, or age 19 if the child is still a full-time high school student and has not yet graduated, under RSA 461-A:14, XI. Support terminates earlier if the child marries, joins the military, is legally emancipated, or dies. New Hampshire does not automatically extend child support for college expenses, but parents may agree to contribute to post-secondary education costs as part of their divorce settlement.
Termination of support for one child in a multi-child order constitutes a substantial change of circumstances under RSA 458-C:7, IV, allowing either parent to petition for recalculation. For example, if a parent pays $1,800 per month for two children and the older child turns 18, the remaining one-child obligation would be recalculated using current incomes and the one-child guideline percentage, which could result in a reduction of 25-35% depending on the income bracket.
New Hampshire courts may order a parent to maintain life insurance to secure future child support obligations. The policy amount typically equals the total remaining support obligation, and the child is named as beneficiary. This provision protects the child's financial security if the obligor parent dies before the support obligation ends.
Filing for Child Support in New Hampshire: Court Process and Fees
New Hampshire handles child support through the Family Division of the Circuit Court. The filing fee for a divorce petition involving minor children is $252 as of March 2026, which includes the child support determination. For parents who were never married, a standalone child support petition can be filed separately through DHHS Child Support Services or directly with the court. Verify current fees with the New Hampshire Judicial Branch at courts.nh.gov.
Parents who cannot afford the filing fee may request a fee waiver by filing a Motion to Waive Filing Fees and Costs with the court. New Hampshire grants fee waivers to parties whose household income falls below 125% of the federal poverty guidelines ($19,506 for a single-person household in 2026). The court evaluates each request individually based on the applicant's financial affidavit.
New Hampshire requires both parents to complete and exchange financial affidavits (Form NHJB-2065-F) disclosing all income, expenses, assets, and liabilities. This disclosure is mandatory under court rules and provides the factual basis for calculating child support. Failure to disclose income can result in the court imputing income at a level the judge deems appropriate based on available evidence.
Frequently Asked Questions About New Hampshire Child Support
How does the New Hampshire child support calculator determine the payment amount?
The child support calculator New Hampshire provides through DHHS applies the income shares formula under RSA 458-C:3. Both parents' net incomes are combined, a guideline percentage is applied (25.6% for one child at incomes of $15,000 or less, decreasing to 19% at $125,000 or more), and the resulting amount is divided proportionally based on each parent's share of the combined income.
What income is included when calculating child support in New Hampshire?
New Hampshire includes all income from any source under RSA 458-C:2: wages, salaries, commissions, bonuses, dividends, pensions, interest, trust income, Social Security benefits, workers' compensation, unemployment insurance, disability benefits, and veterans' benefits. The court may also impute income to a voluntarily unemployed or underemployed parent based on earning capacity.
Can New Hampshire child support be modified after the divorce is final?
New Hampshire permits child support modification at any time upon showing a substantial change in circumstances under RSA 458-C:7. Additionally, either parent may request recalculation every 3 years without proving changed circumstances. Modifications take effect from the filing date, not retroactively, so parents should file promptly when circumstances change.
How long does child support last in New Hampshire?
Child support in New Hampshire continues until the child turns 18, or until age 19 if the child is still enrolled as a full-time high school student under RSA 461-A:14, XI. Support ends earlier upon the child's marriage, military enlistment, legal emancipation, or death. New Hampshire does not mandate college support, though parents may agree to it voluntarily.
What happens if a parent does not pay child support in New Hampshire?
New Hampshire enforces unpaid child support through wage garnishment, tax refund interception, license suspension (driver's and professional), passport denial for arrears over $2,500, property liens, credit bureau reporting for arrears over $1,000, and contempt proceedings carrying up to 12 months imprisonment. Contact DHHS Child Support Services at 1-800-852-3345 ext. 14427 to report nonpayment.
Does parenting time affect child support in New Hampshire?
New Hampshire courts may adjust child support based on the parenting time schedule under RSA 458-C:5. When the noncustodial parent exercises parenting time substantially exceeding a standard schedule, courts may reduce the obligation to reflect direct expenses incurred during that time. New Hampshire does not use a specific overnight threshold but evaluates the actual division of parenting responsibilities.
How is health insurance handled in New Hampshire child support orders?
New Hampshire requires both parents to contribute to the child's health insurance premium proportionally based on their respective incomes under RSA 458-C:3, V. The parent carrying the insurance receives a credit, calculated by dividing the total premium by the number of people covered and multiplying by the number of children. Uninsured medical expenses are typically split proportionally between parents.
Can a parent request a deviation from the New Hampshire child support guidelines?
New Hampshire courts may deviate from guideline amounts under RSA 458-C:5 when the standard calculation would be unjust or inappropriate. Deviation factors include extraordinary medical or educational expenses, significantly different living costs, the parenting time schedule, support of other dependents, and the child's own financial resources. The court must make written findings explaining the deviation.
Where can I find the official New Hampshire child support worksheet?
The official child support guidelines worksheet (Form NHJB-2101-FP) is available at courts.nh.gov under the Family Division forms section. The online child support calculator is available at business.nh.gov/dhhs_Calculator through the DHHS website. Both tools use the guideline table published under RSA 458-C:3 and are updated annually.
How much does it cost to file for child support in New Hampshire?
The filing fee for a divorce petition with minor children in New Hampshire is $252 as of March 2026. A standalone child support petition filed through DHHS Child Support Services has no fee to the custodial parent. Modification petitions cost approximately $100-$125. Fee waivers are available for households earning below 125% of the federal poverty level ($19,506 for one person in 2026). Verify current fees at courts.nh.gov.