New Mexico Child Support Calculator

New Mexico uses the income shares model under NMSA § 40-4-11.1, combining both parents' gross monthly incomes to determine the total child support obligation from the Basic Child Support Schedule. Each parent pays a proportional share based on their percentage of combined income. Worksheet A applies to sole custody (less than 35% overnight time), while Worksheet B applies to shared responsibility arrangements where each parent has at least 35% of overnights.

New Mexico considers gross income from all sources, including wages, salary, bonuses, commissions, self-employment earnings, rental income, investments, Social Security benefits, and unemployment benefits under NMSA § 40-4-11.1(C). Courts may impute income if a parent is voluntarily unemployed or underemployed. A subsequent spouse's income cannot be counted as an increase in the remarried parent's income. The 2024 guidelines recommend using labor market data when imputing income, noting New Mexico's average work week is 34.1 hours.

Custody time directly determines which worksheet New Mexico courts use. Worksheet A applies when the noncustodial parent has less than 35% of overnight time per year, calculating a standard proportional obligation. Worksheet B applies to shared responsibility arrangements with at least 35% overnight time per parent, multiplying the basic obligation by 1.5 before dividing proportionally — resulting in a different calculation that accounts for both households' expenses.

Either parent can request a child support modification by demonstrating a material and substantial change in circumstances, such as a significant income change, increased child expenses, or altered custody arrangements under NMSA § 40-4-11.5. For cases enforced through the state Title IV-D agency, either parent can request a review every three years. The 2024 guideline updates under SB223 do not automatically change existing orders — modifications must be filed separately.

Beyond the basic support obligation, New Mexico requires both parents to share health insurance premiums, dental insurance costs, and work-related childcare expenses proportionally based on each parent's income percentage. Extraordinary uninsured medical and dental expenses exceeding $100 per child per year are also divided proportionally. These add-on costs are calculated separately from the Basic Child Support Schedule amount and added to each parent's total obligation.

New Mexico's Basic Child Support Schedule covers combined parental incomes up to $30,000 per month. Cases exceeding that threshold are handled on a case-by-case basis with additional factors considered. For low-income payers, the 2024 guidelines introduced a $1,200 monthly self-support reserve — ensuring paying parents near the poverty line retain enough income for basic subsistence needs. The self-support reserve applies only to Worksheet A calculations, not shared responsibility Worksheet B.

Child support in New Mexico continues until the child turns 18, or until age 19 if the child is still attending high school, under NMSA § 40-4-7(b)(3)(b). Support may continue indefinitely for a child with a physical or mental disability who cannot become self-sufficient. Parents can voluntarily agree in writing to extend support beyond these ages — for example, to fund college — and New Mexico courts will enforce such written agreements.

New Mexico's Child Support Enforcement Division under the Support Enforcement Act (NMSA §§ 40-4A-1 to 40-4A-20) has broad enforcement tools including automatic income withholding, suspension of driver's licenses, professional licenses, and hunting or fishing licenses. Persistent nonpayers may be placed on New Mexico's '25 Most Wanted' non-payment list. Unpaid child support can be collected for up to 14 years from the date each payment was due, and arrears survive even after the child turns 18.