Massachusetts Child Support Lawyers

Massachusetts calculates child support using the Child Support Guidelines, a formula applied by every judge in the Trial Court. The current version took effect on December 1, 2025. It produces a presumptive amount based on both parents’ gross income, the parenting schedule, the number and ages of the children, and certain costs each parent pays.

A Guidelines worksheet must be completed and filed in every case where support may be established or modified, regardless of what the parents earn.

How is child support calculated in Massachusetts?

Through the Child Support Guidelines worksheet. The formula takes each parent’s gross income, applies the percentages in Table A up to a combined income maximum, and adjusts for the parenting schedule, the number of children, their ages, and amounts paid for child care, health insurance, and dental or vision coverage.

The 2025 Child Support Guidelines took effect December 1, 2025, as amended October 30, 2025, and supersede all previous versions. They are promulgated by the Chief Justice of the Trial Court and reviewed every four years by a court-appointed task force, as federal regulation requires under 45 C.F.R. § 302.56. They are not enacted by the Legislature; the statutes underlying child support are a separate track.

Two rebuttable presumptions apply: that the Guidelines govern the case, and that the amount the worksheet produces is the appropriate amount of support.
Those presumptions apply whether the parents are married or unmarried, whether the order is temporary or final, and when the court is approving an agreement.
The worksheet is form CJ-D 304. A Findings and Determinations for Child Support and Post-Secondary Education form, CJ-D 305, must also be filed whenever a deviation is requested or agreed to.
The formula covers families with one to five children. For more than five, the order should be at least the amount ordered for five.

What counts as income under the Guidelines?

Gross income from whatever source, whether or not it is recognized by the Internal Revenue Code or reported to any taxing authority. The Guidelines list thirty categories. Income from means-tested public assistance, including TAFDC, SNAP, and Supplemental Security Income, is excluded from that parent’s income.

The enumerated sources include:

Salaries, wages, overtime, tips, commissions, bonuses and severance pay.
Income from self-employment and income derived from businesses or partnerships.
Distributions and income from trusts, and income from an interest in an estate.
Net rental income, and capital gains in real and personal property transactions to the extent they represent a regular source of income.
Income derived from stock options and similar incentives, excluding the coverture portion allocated at the time of the divorce.
Pensions, annuities, unemployment compensation, workers’ compensation, and social security retirement or disability benefits.
A catch-all provision reaching any other form of income or compensation, which the 2025 commentary notes includes income from digital assets.

Overtime and secondary employment are treated separately. The court may consider none, some or all of that income. Where a parent begins working overtime or takes a second job after the order enters, and was not doing so before, there is a presumption that the income should not be counted in a future order.

How is income determined for a self-employed parent or business owner?

Income from self-employment, a proprietorship, or joint ownership of a partnership or closely held corporation is gross receipts minus the ordinary and necessary expenses required to produce income. The Guidelines state that in many cases this figure will differ from business income calculated for tax purposes.

That distinction is the center of most disputes over a business owner’s support obligation. The Guidelines commentary cites Whelan v. Whelan, in which the Appeals Court held that a judge must determine whether claimed business deductions are reasonable and necessary to the production of income, without regard to whether those deductions may be claimed for federal or state tax purposes.

The Guidelines also provide two separate mechanisms for reaching income a parent has not documented:

Imputation applies where a parent has undocumented or unreported income. The court may impute income based on all the evidence, including the parent’s ownership and maintenance of assets, lifestyle, expenses and spending patterns.
Expense reimbursements, in-kind payments, personal use of business property, and personal expenses paid by a business may be counted as income where the payments are significant and reduce personal living expenses.
Where income is unreported, the court may adjust the figure upward by a reasonable percentage to account for the income taxes that would otherwise have been due.
Attribution is a different mechanism. It applies where the court finds a parent capable of working is unemployed or underemployed, and assigns potential earning capacity rather than actual earnings. Incarceration may not be treated as voluntary unemployment.

For a parent who holds an interest in an S corporation, the Guidelines commentary cites J.S. v. C.C., in which the Supreme Judicial Court held that whether and to what extent undistributed corporate earnings are available income for child support must be determined on the particular circumstances of each case.

What happens when the parents’ combined income is above $450,000?

The Guidelines are calculated up to a maximum combined available annual gross income of $450,000. Where combined income exceeds that figure, the Guidelines apply to the first $450,000, the amount produced at that level becomes the minimum presumptive order, and support on the income above it is at the court’s discretion.

The maximum rose from $400,000 under the 2023 Guidelines. More income is now captured in the base calculation.
Any percentage the court applies to the payor’s income above the maximum should be below the ten percent applied at the maximum level in Table A, adjusted for the number and ages of the children.
Below the maximum, the Guidelines apply to the first $450,000 in the same proportion as the recipient’s and payor’s actual income.

Does parenting time change the child support amount?

The basic calculation assumes the children have a primary residence with one parent and spend approximately one-third of the time with the other. A single worksheet handles every parenting plan type, and the schedule entered into it affects the presumptive amount.

Shared plans, split plans where each parent provides a primary residence for at least one child, and approximately two-thirds and one-third plans all run through the same worksheet.
Where parenting time is substantially less than one-third for the parent who is not the residential parent, the court may deviate by an upward adjustment.
Where parenting time is substantially more than one-third but less than one-half, the court may deviate by adjustment.
Where children have more than two legal parents, the court considers the financial circumstances and parenting time of the legal parents. This provision was added in 2025 following amendments to chapter 209C.

One-third is the only proportion the Guidelines use as a baseline. No other percentage appears in the parenting time provisions.

Does shared custody eliminate child support?

No. Under M.G.L. c. 208 § 31, an award of shared legal or physical custody does not affect a parent’s responsibility for child support, and a shared custody order is not grounds for modifying a support order absent a demonstrated economic impact sufficient to warrant modification.

The parenting schedule is an input to the worksheet, which is a separate matter from the custody arrangement cancelling the obligation. A shared plan may change the number the worksheet produces. It does not remove the duty of support.

How are child care, health insurance and medical costs handled?

Reasonable out-of-pocket child care costs actually paid, up to $430 per week per child, are shared in proportion to each parent’s share of combined available income. Health care and dental or vision premiums are deducted from the gross income of the parent who pays them. Uninsured medical expenses are allocated separately.

The child care benchmark rose from $355 to $430 per week per child in 2025. It is based on the average cost of center-based infant care in Massachusetts.
The benchmark does not require a parent to spend $430. It caps the amount of child care cost eligible to be shared, and the cost must be necessary for the gainful employment of a parent.
The parent claiming the cost is responsible for providing reasonable evidence of the out-of-pocket amount actually paid, after any discounts or subsidies.
Whether a summer camp counts as child care or as an extracurricular activity depends on factors including whether the camp is necessary to supervise the child so the parent can work, attend school or participate in job training.
Health care coverage is deemed reasonable in cost where it does not exceed five percent of the gross income of the party ordered to provide it, and accessible where covered services are available within fifteen miles of the child’s primary residence.
The recipient is responsible for the first $250 each year in combined routine out-of-pocket and uninsured medical, dental and vision expenses for all children covered by the order. Above that, the court allocates the expenses without adjusting the support order.

Other child-related expenses — extracurricular activities, private school, or summer camps that do not qualify as child care — are discretionary and determined case by case. The court considers whether the expenses are affordable and in the child’s best interest.

What if the Guidelines amount is more than a parent can afford?

The court may deviate above or below the presumptive amount, including setting support at $0. Where application of the Guidelines would require a payor to pay forty percent or more of the payor’s available income for a current support order, a rebuttable presumption of substantial hardship arises, justifying a deviation.

A deviation requires specific written findings stating the amount the Guidelines would produce, that the amount would be unjust or inappropriate under the circumstances, the specific facts justifying departure, and that the departure is consistent with the child’s best interests. The Guidelines list fifteen circumstances that may support one, including:

A child has ongoing special needs or aptitudes with financial consequences.
A child or a parent has ongoing extraordinary mental, physical, or developmental needs with financial consequences.
A parent has extraordinary expenses for health care coverage, for travel related to parenting time, or for child care.
The payor is incarcerated and has insufficient financial resources to pay support.
Application of the Guidelines leaves a parent without the ability to support themselves, particularly in low-income cases.
Application would result in a gross disparity in the standard of living between the two households.

At the low end of the income scale, the Guidelines set their own limits. For a payor whose gross income is $301 per week or less, an order of no more than $15 per week should enter. Between $302 and $391 per week, an order of no more than $33 per week should enter.

How long does child support last in Massachusetts?

Massachusetts permits support past age 18. Under M.G.L. c. 208 § 28 and the parallel provisions for unmarried parents, support may be ordered for a child between 18 and 21 who is domiciled with a parent and principally dependent on that parent, and for a child between 21 and 23 where that dependence results from enrollment in an educational program.

Ordering support for a child 18 or older is discretionary. The court may order it or decline to.
A child 18 or older who is enrolled in and attending high school is treated as under 18 for Guidelines purposes.
The educational program may not be beyond an undergraduate degree.
Where support is ordered for a child 18 or older who is not in high school, the worksheet reduces the amount through Table C.
In deciding whether to order support for a child 18 or older, the court considers the reason for the child’s continued residence with and principal dependence on the recipient, the child’s academic circumstances and living situation, the available resources of each parent, and each parent’s contribution to post-secondary costs.

Can a parent be ordered to pay for college?

Contribution to post-secondary educational expenses is discretionary and is not presumptive. Where it is ordered, no parent may be required to pay more than fifty percent of the undergraduate in-state resident costs at the University of Massachusetts Amherst, unless the court enters written findings that the parent has the ability to pay more.

Post-secondary educational expenses include mandatory fees, tuition, on- or off-campus housing, meal plan, and books.
The fifty percent cap applies to all such orders regardless of where the child lives or attends school.
The Guidelines give the benchmark figure directly: as of June 30, 2025, the 2025 to 2026 in-state cost was $35,815 plus $1,200 for books, for a total of $37,015. The figure is republished annually.
In deciding whether to order contribution, the court considers the cost, the child’s aptitudes, where the child lives, the available resources of all parents and the child, affordability, including whether parents would need to use assets or borrow, and the availability of financial aid.
Where the court orders both support for a child over 18 and contribution to educational expenses, it must consider the combined amount.

How does a parent change an existing child support order?

By filing a complaint for modification. A support order may be modified on any of five grounds, and an inconsistency between the existing order and the amount the Guidelines would now produce is sufficient on its own. A parent does not have to prove changed circumstances to modify support.

The five grounds are:

An inconsistency between the amount of the existing order and the amount that would result from applying the Guidelines.
Previously ordered health care coverage is no longer available.
Previously ordered health care coverage is still available, but no longer at reasonable cost or without undue hardship.
Access to health care coverage not previously available to a parent has become available.
Any other material and substantial change in circumstances has occurred.

Where the existing order deviated from the Guidelines when it entered, the court applies that deviation to the modification if the facts giving rise to it still exist, the deviation remains in the child’s best interest, and the Guidelines amount would be unjust or inappropriate. Amounts that have already accrued and gone unpaid are treated as arrears and are handled separately from the ongoing order.

Which court handles child support in Massachusetts?

It depends on whether the parents were married. Between spouses, support is set in the Probate and Family Court as part of a divorce or separate support action. Between parents who were never married, the District Court and Boston Municipal Court share jurisdiction over support complaints with the Probate and Family Court under M.G.L. c. 209C § 3.

A Guidelines worksheet is required in every case establishing or modifying support, whichever court hears it.
Under section 4, a complaint between unmarried parents is filed in the county where the child and one parent live, or where the child lives if neither parent lives in that county.
The District Court and Boston Municipal Court have no authority over custody or parenting time under chapter 209C. A parent in one of those cases who wants a custody or visitation order may, once parentage is established and a support order has entered, file in the Probate and Family Court for the county where the child lives, and that filing transfers the case.
Where a parent lives in another state, the Uniform Interstate Family Support Act governs, with the Department of Revenue serving as the Commonwealth’s support enforcement agency. A Massachusetts court can establish support against a parent living elsewhere on listed grounds, including that the parent lived with the child in Massachusetts or that the child lives here as a result of that parent’s acts or directives.
A Massachusetts order remains modifiable here while the paying parent, the receiving parent or the child still lives in Massachusetts, or where the parties consent in a record or in open court.
Bristol County support cases are heard at the Probate and Family Court in Taunton, Fall River or New Bedford, each of which serves the entire county. Every other county, from Essex to Barnstable, has its own division.

Request a case evaluation

O’Connor Family Law has offices in Westborough and Hanover and represents parents throughout Central and Eastern Massachusetts, including Worcester, Middlesex, Norfolk, Plymouth and Bristol counties, in child support matters, including support for self-employed and business-owner parents, modifications, and enforcement. Request a free case evaluation to go over your situation, your options, and whether the firm is the right fit for your case.

Frequently asked questions about child support in Massachusetts

Does a worksheet have to be filed if both parents already agree on an amount?

Yes. A Guidelines worksheet must be completed and submitted in every case where a support order may be established or modified, regardless of the parties’ income. The presumption that the Guidelines produce the appropriate amount applies even where the court is being asked to approve an agreement.

Is child support taxable to the parent who receives it?

The Guidelines were developed with the understanding that child support is non-deductible by the payor and non-taxable to the recipient. The Guidelines do not prevent the court from designating a support order in whole or in part as alimony or unallocated support, provided the tax consequences are considered. The parties are responsible for presenting those consequences to the court.

Does a parent get credit for supporting children from another relationship?

A parent who is actually paying a pre-existing support order for a child or spouse not involved in the current case may deduct that amount from gross income, on sufficient proof of the order and the payments made. Payments toward arrearages are not deducted. Separate provisions address voluntary payments and children living in the parent’s own household.

How does alimony affect the child support calculation?

It depends on who pays it. Alimony received from a person who is not a party to the support order is a listed source of income. Where the parents in the case are also resolving alimony between themselves, the court calculates the two orders in both sequences and compares the results before entering either, as the Supreme Judicial Court required in Cavanagh v. Cavanagh.

What happens to support that has already gone unpaid?

Unpaid support accumulates as arrears and is addressed separately from the ongoing order. Payments made toward arrears are not deducted from a parent’s gross income when a new order is calculated.

This page is provided for informational purposes only and does not constitute legal advice. Reading it or contacting our firm does not create an attorney-client relationship. Prior results do not guarantee a similar outcome. Child support outcomes depend on the specific facts of each case.

Last reviewed: October 2026