How Much Is Child Support in Massachusetts: Income, Custody, and Add-Ons

Child support in Massachusetts runs from a floor of $15 per week for a parent earning $301 per week or less up through amounts calculated on combined parental income as high as $450,000 per year, with the actual figure set by a formula that splits the obligation between the two parents in proportion to what they earn. The 2025 Child Support Guidelines, effective December 1, 2025, apply to every order entered or modified after that date and cover the number of children, each parent’s income, the parenting schedule, childcare, and health insurance.¹

Massachusetts uses an income shares model. The court looks at what both parents make, assigns each a share of the total support obligation based on their percentage of combined income, and the parent with less parenting time typically pays their share to the other. The guideline amount is presumed correct unless a parent shows the court a specific reason to depart from it.²

What Counts as Income in the Calculation

The income figure that goes into the formula is broad. It includes gross income from any source, whether or not it’s reported to the IRS: wages, salaries, overtime, tips, bonuses, commissions, self-employment earnings, investment dividends, rental income, trust distributions, workers’ compensation, unemployment, Social Security disability, lottery winnings, and regular perks like a company car.³

Means-tested public benefits are excluded from the recipient parent’s income. That covers TAFDC, SNAP, Supplemental Security Income, and certain veterans’ benefits.³

If a parent could earn more but doesn’t, the court can impute income based on earning capacity, weighing age, education, skills, work history, health, criminal record, and whether jobs at that level actually exist locally. Incarceration, though, cannot be treated as voluntary unemployment.³

Existing child support obligations from prior orders and alimony payments come off a parent’s income before the formula runs.

How Custody Affects the Amount

The parenting schedule changes what the formula produces. The guidelines recognize three general arrangements:

Primary custody: one parent has the child roughly two-thirds of the time or more, and the other pays the calculated amount.
Shared custody: each parent has the child approximately half the time, and the amount is adjusted because both households carry direct costs.
Limited parenting time: one parent has the child less than one-third of the time, and the calculation reflects that parent’s lower direct expenses.

A parent whose actual time doesn’t fit these categories cleanly can ask the court to deviate to match the real arrangement.⁴

Childcare and Health Insurance Add to the Order

The base support figure is not the whole obligation. Work-related childcare costs are shared in proportion to income, up to a cap of $430 per week per child after any discounts or subsidies. That cap went up under the 2025 Guidelines.⁵

Health and dental insurance premiums for the children are also factored in. Coverage is treated as reasonable in cost if it doesn’t exceed 5% of the providing parent’s gross income, and accessible if covered services are available within 15 miles of the child’s primary residence.¹

The Low-Income Floor

The guidelines protect parents at the bottom of the income scale. For a parent earning $301 per week or less, roughly $15,650 a year, the presumptive order is no more than $15 per week. Between $302 and $391 per week, the order caps at $33 per week. Those thresholds track 100% and 130% of the federal poverty guideline for a one-person household, and the court can set the amount at $0 when circumstances call for it.¹

A broader safety valve applies further up the income scale. When the formula would take 40% or more of a parent’s available income, a rebuttable presumption of substantial hardship applies, and the court has grounds to reduce the amount.⁴

The High-Income Ceiling

The formula covers combined parental income up to $450,000 per year. Above that, the court applies the formula to the first $450,000 and treats the result as the minimum presumptive order. The court has discretion to add more support for income above the cap, but any percentage applied to the payor’s income above $450,000 should be lower than the percentage that applies at the cap (10% at the cap level, adjusted for the number and ages of children).⁵

When Courts Order a Different Amount

The guideline figure is a starting point. A court can order more or less, but it has to identify the guideline amount in writing, explain why applying it would be unjust or inappropriate, describe the specific facts supporting the departure, and confirm the deviation serves the child’s best interests.²

The 2025 Guidelines list circumstances that may support a deviation, including:⁴

Both parents agree to a different amount and the court finds it fair.
The child has ongoing extraordinary mental, physical, or developmental needs, or special aptitudes, with financial consequences.
A parent has ongoing extraordinary health or developmental needs with financial impact.
Health insurance premiums are well above typical levels.
Travel for parenting time carries unusual costs because parents live far apart.
Childcare expenses go beyond what the formula contemplates.
One parent has substantially more or less than one-third of the parenting time.
The child has more than two legal parents sharing financial responsibility.
The paying parent is incarcerated and lacks financial resources.
The formula would leave a parent unable to meet basic living expenses.
One household ends up with an unreasonably low share of the combined income.
Applying the formula could interfere with reunification after a temporary removal.
Any other situation where the formula would produce an unjust result contrary to the child’s best interests.

How Long the Payments Continue

Child support in Massachusetts generally lasts until the child turns 18. The court can extend it in two situations. For a child between 18 and 21 who lives in a parent’s home and depends primarily on that parent, the court can order continued maintenance, support, and education costs. For a child between 21 and 23, support can continue if the child lives in a parent’s home, is still principally dependent, and is enrolled in an educational program; support for educational costs at this stage cannot go beyond an undergraduate degree.⁶

When the court orders a parent to contribute to post-secondary costs, neither parent can be required to pay more than 50% of the in-state undergraduate cost at UMass Amherst, unless the court specifically finds that parent has the ability to pay more.¹

Estimating Your Own Number

The state publishes a guidelines chart showing support amounts at various income levels along with a worksheet, Form CJD 304, that walks through the actual calculation.⁷ To run your own numbers you’ll need each parent’s gross weekly income, the weekly cost of health and dental insurance for the children, work-related childcare expenses, and the parenting schedule. Existing court-ordered support for other children and any alimony come off the income figures before the formula runs.

One note on modifications: even if your circumstances have changed or the current order looks inconsistent with the updated guidelines, the amount doesn’t change on its own. Only the court that issued the order can change it, and until it does, the original amount remains enforceable and any shortfall accumulates as arrears.⁸ Massachusetts law creates a presumption in favor of modification when an existing order is inconsistent with the current guidelines, so if the 2025 figures would produce a meaningfully different amount, that’s grounds to file.²

1
Mass.gov. Child Support Guidelines 2025
2
Mass.gov. Massachusetts General Laws c208 Section 28
3
Mass.gov. 2025 Child Support Guidelines Section I – Income Definition
4
Mass.gov. 2025 Child Support Guidelines Section IV – Deviation
5
Mass.gov. 2025 Child Support Guidelines Section II – Factors to Be Considered in Setting the Child Support Order
6
Mass.gov. Massachusetts Law About Child Support Over Age 18
7
Mass.gov. Child Support Guidelines
8
Mass.gov. Learn About Changing a Child Support Order