Quick answer: Massachusetts uses the percentage-of-income guidelines of the Trial Court, in effect from December 1, 2025. Each parent’s gross weekly income, less health care and dental/vision premiums and existing support obligations, is the parent’s available income. Table A turns the combined available income into a support amount for one child, with a marginal percentage that falls from 22% to 10% as income rises (up to $8,654 a week, or $450,000 a year); Table B multiplies it for more children (1.40, 1.68, 1.85, 1.94); and Table C reduces the part for a child 18 or older. The recipient is presumed to spend his or her income share directly on the child, and the payor owes the rest plus a share of child care, up to $430 a week per child. Payors with very low incomes owe $15 to $33 a week.
How the Massachusetts worksheet works
- Available income. Gross weekly income minus health care, dental/vision and existing support. See child care, low income and high income.
- Table A. One child at the combined income, with tranches at $301, $391, $1,000, $1,600, $2,400, $3,500, $5,000 and $8,654.
- Tables B and C. The number and ages of the children.
- Shares and child care. The payor pays the non-recipient share plus a share of child care.
- Parenting arrangement. Primary, shared or split. See shared, split and primary care.
The full walk-through, with a worked example, is in how Massachusetts calculates child support.
What this calculator checks
The engine is a port of the official worksheet CJD 304 (effective December 1, 2025), line by line, and was checked against an independent re-implementation. Social Security dependency benefits, deviations and the discretionary support above $450,000 are not included, and the guideline amount is a rebuttable presumption.
Child support across Massachusetts
The guidelines apply in every Probate and Family Court division, from Boston, Worcester, Springfield, Cambridge, Lowell or Brockton, whether the parents are married or not. A worksheet must be filed in every case that sets or modifies child support.
Frequently asked questions
How is child support calculated in Massachusetts?
Each parent's weekly available income is combined, Table A gives a support amount for one child, Table B adjusts it for the number of children, and the payor owes the part not attributed to the recipient plus a share of child care.
What is the minimum child support order in Massachusetts?
$15 a week for a payor with gross income of $301 a week or less, and no more than $33 a week for a payor with income between $302 and $391 a week.
What is the maximum income in the Massachusetts child support guidelines?
$450,000 a year of combined available income, or $8,654 a week. Support on income above that is at the court's discretion.
Does Massachusetts child support cover children over 18?
The court has discretion to order support for a child 18 or older, up to age 23 in some cases, and Table C reduces the amount for those children.
How much child care is shared in Massachusetts?
Reasonable out-of-pocket child care costs, up to $430 a week per child, are shared in proportion to the parents' available income.