Massachusetts Child Support Calculator (2026)

How Massachusetts calculates child support

Massachusetts uses the income-shares model under the Child Support Guidelines issued by the Chief Justice of the Trial Court under M.G.L. c. 208, § 28 and c. 209C, § 20. The 2025 guidelines took effect December 1, 2025 and are the ones applied to orders entered in 2026.

The worksheet works in weeks. It adds the parents’ available incomes, applies the $8,654 cap, finds the weekly amount for one child on the chart, multiplies by the Table B factor for the number of children, and divides the total by each parent’s share of the combined income. The parent with less parenting time pays that share.

This page reproduces the basic calculation. The official worksheet also handles children 18 to 23, childcare, health insurance, and deviations.

The chart is a step table, not a formula

The chart lists weekly support amounts for one child, from $15 at zero income up to $1,174 at the $8,654 cap. It is a step table: each row is the income at which the amount rises by one dollar, and an income between two rows takes the lower amount.

The shaded region at the bottom of the chart runs up to $391 a week of the paying parent’s available income. There, the chart amount is the order regardless of the other parent’s income, and it is not multiplied by an income share. That protects low-income payors from an order that scales with a high-earning co-parent.

Above the cap, the amount at $8,654 is the minimum presumptive order and the court may increase it. The 2025 guidelines raised the cap from $400,000 to $450,000 a year.

Available income and the deductions

Income is defined broadly: wages, overtime, tips, commissions, bonuses, self-employment and business income, interest, dividends, rent, pensions, Social Security, unemployment, workers’ compensation, and more. Means-tested benefits such as TAFDC, SNAP, and SSI are excluded.

The deductions are narrow. A parent subtracts the health, dental, and vision insurance premiums actually paid for the children, and support paid under another order. Ordinary living expenses, retirement contributions, and voluntary deductions are not subtracted, which is why the input is not take-home pay.

The court can attribute or impute income when a parent is voluntarily unemployed or underemployed, and it can consider overtime and secondary jobs. A calculator that takes one weekly figure per parent cannot reproduce those findings.

Table B: more than one child

The chart gives the amount for one child. Table B multiplies it by 1.40 for two children, 1.68 for three, 1.85 for four, and 1.94 for five. The 2025 guidelines replaced the older factors (1.25, 1.38, 1.45, 1.48), so amounts for larger families rose.

For more than five children, the order should be at least the five-child amount. This calculator stops at five and says so, because the guidelines do not publish a factor for six.

Parenting time, age, and add-ons

Massachusetts uses one worksheet for shared, split, and two-thirds/one-third parenting plans. There is no separate timeshare formula in the guidelines; parenting time can support a deviation, with written findings. This estimate shows the presumptive amount before any deviation.

Table C reduces the part of the support attributable to a child who is 18 or older and still in school. Childcare needed for work is shared in proportion to income, up to $430 per child per week. Health insurance and uninsured medical costs are handled separately on the worksheet. None of those adjustments are included here.

A Massachusetts example at $2,000 a week

Parent A earns $1,500 and Parent B earns $500 of weekly available income, with one child. Combined income is $2,000, and the chart gives $418. Parent A’s 75% share is $313.50 a week, or about $1,359 a month.

With two children, Table B matters: Parent A at $3,000 and Parent B at $2,000 gives $5,000 of combined income, a chart amount of $809, and a two-child total of $1,132.60. Parent A’s 60% share is $679.56 a week, or about $2,945 a month. In the shaded region, Parent A at $350 with one child pays the chart amount of $25 a week, about $108 a month, whatever Parent B earns.

When the official worksheet is the better choice

The CJD 304 worksheet handles the full calculation: available income, Table B, Table C for children 18 or older, childcare, health insurance, and deviations. Use it if the parents share parenting time, if a child is 18 or older, or if income must be attributed.

A Massachusetts family law attorney is the right next step when the parents disagree about income or parenting time. The guideline amount is the starting point; the court’s order controls.

Frequently asked questions