Support in Massachusetts (2026)

The Massachusetts Child Support Guidelines Worksheet

Massachusetts uses a distinctive worksheet-based system for calculating child support that sets it apart from many other income shares states. The Massachusetts Child Support Guidelines, promulgated by the Trial Court under M.G.L. c. 211B Section 15, provide a standardized worksheet that both parents and the court complete to determine the presumptive child support obligation. The current guidelines were most recently revised and took effect in 2021.

The worksheet walks through the calculation step by step. It begins with each parent’s gross weekly income from all sources, then applies specific deductions — including the cost of health insurance, dental and vision insurance, child care costs, and support obligations for other children. The parents’ available incomes are combined, and the worksheet references a schedule that correlates combined income levels with the basic cost of raising children. Each parent’s share of the total obligation is proportional to their percentage of the combined available income.

What makes the Massachusetts worksheet particularly detailed is its treatment of different parenting arrangements. The guidelines include separate calculation methods for cases where one parent has primary physical custody, where parents share physical custody (each parent has the child approximately one-third or more of the time), and where parents split custody of multiple children. The worksheet also accounts for the interaction between child support and alimony — under the guidelines, alimony payments reduce the payor’s available income and increase the recipient’s, preventing double-counting. Courts may deviate from the worksheet amount, but must provide written findings explaining why the guidelines result would be unjust or inappropriate.

How Massachusetts Calculates Child Support

Massachusetts uses an income shares model under the Massachusetts Child Support Guidelines, which have been in effect since 2009 and were most recently updated to reflect current economic data. The guidelines are promulgated by the Trial Court and apply a formula based on both parents’ incomes and the costs of raising children.

The calculation starts with each parent’s gross weekly income from all sources, including wages, salaries, tips, commissions, bonuses, overtime, pensions, Social Security, workers’ compensation, unemployment benefits, rental income, and investment income. Self-employment income is included after reasonable business deductions. Courts may impute income to a parent who is unemployed or underemployed without good cause.

Each parent’s gross income is then reduced by certain deductions, including the cost of health insurance, dental and vision insurance, child care costs, and support obligations for other children. The parents’ available incomes are combined and applied to the guidelines schedule, which produces a basic support amount. Each parent’s share is proportional to their percentage of the combined available income.

For a broader overview of how income shares models function, see our guide on how child support is calculated. You can also run preliminary numbers with our child support calculator.

Parenting Time and Custody Adjustments

The Massachusetts Guidelines include specific adjustments for different custody arrangements:

• Shared physical custody. When a child spends approximately one-third or more of the time with each parent, the guidelines apply a formula that accounts for the increased costs associated with maintaining two homes.
• Split custody. When each parent has primary physical custody of at least one child, separate calculations are performed and the obligations are offset.

The court retains authority to deviate from the guidelines amount when it finds that the result would be unjust or not in the best interest of the child. Any deviation must be accompanied by written findings.

Modifying or Terminating Child Support

Either parent may seek a modification by demonstrating a material change in circumstances since the last order. Typical grounds include significant income changes, job loss, changes in the child’s needs, or a change in the parenting schedule.

Child support in Massachusetts continues until the child turns 18, or until age 21 if the child is domiciled in the home of a parent and principally dependent on that parent for support. The court may also order support until age 23 if the child is enrolled in an undergraduate educational program. Support also terminates upon emancipation, marriage, or military service.

Enforcement of Child Support Orders

The Massachusetts Department of Revenue, Child Support Enforcement Division (DOR/CSE) has broad enforcement powers:

• Automatic income assignment from wages
• Interception of state and federal tax refunds
• Suspension of driver’s licenses and professional licenses
• Liens on real and personal property
• Reporting arrearages to credit bureaus
• Contempt of court proceedings, which may include fines or incarceration

Arrearages cannot be retroactively reduced, and any modification takes effect from the date the complaint for modification is filed.

Alimony in Massachusetts

Massachusetts underwent a major overhaul of its alimony laws with the 2011 Alimony Reform Act (M.G.L. Chapter 208, Sections 48-55). Before the reform, alimony awards were largely unpredictable, with no caps on duration and limited guidance for judges. The 2011 Act brought structure and transparency to the process.

The Reform Act established four types of alimony:

• General term alimony. The most common type, providing ongoing periodic support. The amount is generally capped at 30-35% of the difference between the parties’ gross incomes. Duration is tied to the length of the marriage.
• Rehabilitative alimony. Awarded to a spouse who is expected to become self-supporting by a predicted time, typically through employment or completion of a training program. Limited to five years.
• Reimbursement alimony. Compensates a spouse who contributed financially to the other spouse’s education or career advancement during a short marriage (five years or less). Paid for a defined period.
• Transitional alimony. Awarded following a marriage of five years or less to help the recipient adjust to a new lifestyle or location. Limited to three years.

Durational Limits Under the Reform Act

One of the most significant changes brought by the 2011 Act is the establishment of maximum durations for general term alimony based on the length of the marriage:

• Marriage of 5 years or less: alimony duration cannot exceed 50% of the number of months of the marriage
• Marriage of 5-10 years: cannot exceed 60% of the months of marriage
• Marriage of 10-15 years: cannot exceed 70% of the months of marriage
• Marriage of 15-20 years: cannot exceed 80% of the months of marriage
• Marriage of more than 20 years: the court may order alimony for an indefinite length of time

These caps apply to general term alimony and provide clearer expectations for both parties.

Factors in Alimony Determinations

Under M.G.L. Chapter 208, Section 53, the court considers:

• The length of the marriage
• The age of the parties
• The health of the parties
• The income, employment, and employability of both parties
• The economic and noneconomic contribution of both parties to the marriage
• The marital lifestyle
• The lost economic opportunity as a result of the marriage
• The ability of each party to maintain the marital lifestyle

The Reform Act also provides that general term alimony terminates when the payor reaches full retirement age, and it is suspended, reduced, or terminated upon the recipient’s cohabitation with another person for a continuous period of at least three months.

When to Seek Legal Guidance

The 2011 Reform Act brought welcome clarity to Massachusetts alimony law, but applying the durational limits and income caps to your specific facts still requires careful analysis. Whether you are calculating child support or evaluating an alimony claim, consider scheduling a free consultation with an experienced family law attorney.

Statutes referenced: Massachusetts Child Support Guidelines, M.G.L. Chapter 208, Sections 48-55 (Alimony Reform Act of 2011).

Frequently Asked Questions

How is child support calculated in Massachusetts?

Massachusetts uses the income shares model under the Massachusetts Child Support Guidelines. Both parents’ gross incomes are reduced by health insurance, dental/vision insurance, childcare costs, and prior support obligations, then combined and applied to the guidelines schedule. Each parent’s share is proportional to their percentage of combined available income.

How long does child support last in Massachusetts?

Child support continues until the child turns 18, or until age 21 if the child is domiciled with a parent and principally dependent on that parent for support. The court may order support until age 23 if the child is enrolled in an undergraduate educational program. Support also terminates upon emancipation, marriage, or military service.

How does shared custody affect child support in Massachusetts?

When a child spends approximately one-third or more of the time with each parent, the guidelines apply a shared custody formula that accounts for the increased costs of maintaining two homes. This adjustment reduces the net transfer payment compared to a sole custody calculation.

What types of alimony does Massachusetts recognize?

Massachusetts recognizes general term alimony, rehabilitative alimony, reimbursement alimony, and transitional alimony (limited to three years for marriages of five years or less). Duration caps tied to marriage length apply to general term alimony, and the Alimony Reform Act of 2011 established specific rules for modification and termination.

Where can I find the Massachusetts child support guidelines worksheet?

The official worksheet is available through the Massachusetts Probate and Family Court and on Mass.gov. The worksheet is a required court form — both parents must complete it and file it with the court as part of any case involving child support. The guidelines and worksheet are periodically updated by the Trial Court; the most recent version took effect in 2021.

Does alimony affect the child support calculation in Massachusetts?

Yes. Under the Massachusetts Child Support Guidelines, alimony payments are factored into the calculation. Alimony paid by a parent reduces that parent’s available income for child support purposes, while alimony received increases the recipient’s available income. This prevents the same income from being counted toward both obligations simultaneously.

How This Guide Was Researched

This guide was developed by reviewing the Massachusetts Child Support Guidelines (promulgated under M.G.L. c. 211B Section 15), including the guidelines worksheet, income definitions, deviation standards, and shared custody adjustments from the 2021 revision. Alimony provisions were drawn from M.G.L. Chapter 208 Sections 48 through 55 (the Alimony Reform Act of 2011), including Section 49 (types of alimony), Section 50 (general term alimony duration limits), Section 53 (factors in alimony determinations), and Section 54 (modification and termination). Enforcement mechanisms were verified against M.G.L. Chapter 119A and Department of Revenue, Child Support Enforcement Division resources.

Sources and Legal References

This guide draws on the following Massachusetts statutes and official resources:

• Massachusetts Child Support Guidelines (2021) — Promulgated under M.G.L. c. 211B Section 15; income shares model, worksheet, deviation factors, and shared/split custody adjustments
• M.G.L. c. 208 Section 48 — Definitions for the Alimony Reform Act
• M.G.L. c. 208 Section 49 — Types of alimony (general term, rehabilitative, reimbursement, transitional)
• M.G.L. c. 208 Section 50 — Duration limits for general term alimony based on length of marriage
• M.G.L. c. 208 Section 53 — Factors in alimony determinations
• M.G.L. c. 208 Section 54 — Modification and termination of alimony, including cohabitation and retirement provisions
• M.G.L. c. 119A — Child support enforcement authority of the Department of Revenue

Official Massachusetts Resources

• Massachusetts Probate and Family Court
• Child Support Information for Parents — Mass.gov
• Massachusetts Divorce Court Forms

For more about how we research our guides, see our editorial policy and sources methodology.

Related Guides

Massachusetts Support Guides

• Child Support Guidelines in Massachusetts
• Child Support in Massachusetts

Massachusetts Family Law

• Divorce in Massachusetts
• Child Custody in Massachusetts
• The Massachusetts Divorce Process: 1A vs. 1B
• Custody in Massachusetts

National Support Guides

• How child support is calculated
• How to file for child support
• Child support enforcement
• Modifying child support
• Child support guidelines by state
• Complete guide to divorce