Child support in New Mexico.
What the state’s own guideline says, where the number comes from, and the one figure that moves it more than anything you will argue about.
See a different stateNew Mexico
New Mexico combines both parents' gross monthly incomes, reads a basic support figure off a statutory schedule, and divides it in proportion to income. Which worksheet you use depends on the parenting schedule: Worksheet A for a basic visitation arrangement, Worksheet B for shared responsibility. Low-income cases get a special Self-Support Reserve treatment where only the paying parent's income is used.
How New Mexico works out the number
Authority: N.M. Stat. Ann. § 40-4-11.1 (1978) (child support guidelines), applied by the state IV-D agency under 8.50.108 NMAC; deviations governed by N.M. Stat. Ann. § 40-4-11.2New Mexico switches worksheets rather than sliding a scale. The state's own official calculator sets the threshold at 127 days: at or below 127 days a year with the non-primary parent you use Worksheet A, and above that you use Worksheet B for shared responsibility. (127 out of 365 days is just under 35%.) We could not read the statutory wording of the threshold itself — see below.
Use the state’s own calculator, not ours
New Mexico publishes this itself, free. It is called Child Support Worksheet A (basic visitation) and Child Support Worksheet B (shared responsibility), both set out in § 40-4-11.1.. We are not going to build a competing calculator and ask you to trust it — this is the one a judge will recognize.
Open the New Mexico calculator →What goes into the calculation
What counts as income
§ 40-4-11.1(C) is unusually specific. “Income” means your actual gross income if you are employed to full capacity, or your potential income if you are unemployed or underemployed. “Gross income” is income from any source and expressly includes salaries, wages, tips, commissions, bonuses, dividends, severance pay, pensions, interest, trust income, annuities, capital gains, social security, workers’ compensation, unemployment, disability insurance, significant in-kind benefits that reduce your living expenses, prizes, and alimony received. So yes — bonuses and commissions count, and there is no carve-out for overtime or a second job. Only your income counts, not a new spouse’s. Four things are excluded: means-tested public assistance such as TANF, SSI and general assistance; the earnings or benefits of the child the award is for; child support you receive for other children; and alimony or child support you actually pay under a court order, plus a reasonable amount for prior children living with you. If you are self-employed or run a business, gross income means gross receipts minus the ordinary and necessary expenses of producing it — but the court can disallow expenses it considers inappropriate for this purpose. A duty to support later children is not usually a reason to reduce support for these children, though it can be a defense against an increase.
When a judge can treat you as earning more
§ 40-4-11.1(D): if the court finds a parent “has willfully failed to obtain or maintain appropriate employment or is willfully underemployed,” it may impute income equal to that parent’s earning and employment potential. Note the word willfully — losing a job is not the same as choosing to earn less. The court weighs eight things: available employment opportunities, employment history, income history, job skills, education, age and health, any history of convictions and incarceration, and whether the parent is caring for a child of the parties who is under six or is disabled. Where a parent has no recent employment or earnings history but could earn minimum wage, minimum wage may be imputed.
If you do not earn much
8.50.108.7 NMAC: 'Self-support reserve means the support calculation ensures the payer parent has sufficient income to maintain a minimum standard of living. The self-support reserve is $1,200 per month for one person which is slightly higher than one hundred percent of the federal poverty guideline.' Effective January 1, 2024 the schedule itself carries a shaded self-support-reserve area: 'if the payer parent's income and number of children fall into the shaded area, only the payer-parent's income is considered in the child support calculation,' making that parent 100% responsible for the reduced obligation regardless of how much the other parent earns. The SSR method uses Worksheet A only and does not take child care, insurance premiums or other add-ons into account. Shared-responsibility (Worksheet B) cases are not eligible for the SSR method.
Childcare and health insurance
Both are added on top of the basic obligation and shared, rather than absorbed into it. On the worksheet, Line 5 is the children’s health and dental insurance premium — each parent enters what they pay to cover these children, and the two are combined. Line 6 is work-related child care, entered the same way; if the cost swings between term time and the summer, you take the yearly total and divide by twelve rather than using this month’s figure. Line 7 carries additional expenses under § 40-4-11.1(J). The combined total is then divided between you in proportion to income, so paying the nursery bill yourself does not mean carrying it alone.
When a judge can depart from the number
§ 40-4-11.2. A judge can depart from the guideline figure, but only with a written finding in the decree or order that applying the guidelines and the basic schedule “would be unjust or inappropriate.” The finding has to state what the guideline amount would have been and justify why the order differs — so a deviation you do not understand is a deviation the order is required to explain. Circumstances creating a substantial hardship for either parent or for the children may justify going up or down.
Two practical points. First, if your income is low, New Mexico may run your case under the Self-Support Reserve method — and that method ignores the other parent's income entirely and also ignores child care and insurance costs. It can produce a very different result from the ordinary worksheet, in both directions. Second, the day count matters more than in most states because it does not adjust the number gradually — it changes which worksheet you use. The state's own calculator flips from Worksheet A to Worksheet B above 127 days a year, so a parenting plan sitting right around 125 to 130 days deserves careful attention.
Later on
When it ends
The New Mexico Supreme Court's approved Child Support Obligation and Order (Form 4A-303 NMRA) states it plainly: 'Payments shall continue each month until the youngest child turns eighteen (18); however, if the youngest child turns eighteen (18) while still attending high school, payments shall continue until the month the child graduates or turns nineteen (19), whichever occurs first.'
College and support after 18
We could not confirm whether a court here can order support for college.
Changing the amount later
For cases the state child support agency handles, 8.50.108.13 NMAC: the agency reviews orders three years from the effective date of the last order, and where public assistance is involved 'the IV-D agency must pursue a modification either upward or downward if its review indicates that there will be at least a twenty percent change from the current obligation of support.' The agency may also review without a request if it learns the non-custodial parent will be incarcerated for more than 180 calendar days. Either parent may pursue their own modification even if the agency declines.
How far back a change can reach
8.50.108.12 NMAC: 'a modification of a support order is retroactive only to the time period that a petition or motion was filed with a court and was pending a decision.' On a first order, the agency will only seek 'the minimal period in accordance with New Mexico law'; a custodial parent who wants a longer retroactive period may seek it but 'is solely responsible for providing all documentation, presenting all evidence, and making all arguments.'
If someone stops paying
Wage withholding is the default. 8.50.108.8 NMAC: 'The IV-D agency will not agree to an exception to wage withholding' and 'All payments on Title IV-D cases, whether paid through income withholding, direct withdrawal, or direct payment by the non-custodial parent shall be paid through the IV-D agency.' If a custodial parent gets an order for direct payments in an agency case, the agency starts non-cooperation procedures or closes the case. The Supreme Court's order form warns that 'If child support is not paid in a timely manner, interest will be added to the amount owed at the rate provided by law' and cites N.M. Stat. Ann. § 40-4-7.3.
What we could not confirm
- The basic child support schedule itself — the dollar table the worksheet reads across — is set by department rule rather than printed in the statute, and was moved to rule by a 2023 amendment effective 1 January 2024. Use the state’s own calculator rather than any table you find elsewhere, because an out-of-date schedule produces a confidently wrong number.
Compare all fifty states
The overnight thresholds, the ending ages and the college rules, side by side.
The rest of what we have written about New Mexico. Every figure is quoted from New Mexico’s own statute or its courts’ own published schedule, and carries the date we last checked it.