Massachusetts Child Support Calculator (2025)

Estimate your Massachusetts child support obligation using the Income Shares model. Enter both parents' gross income, number of children, and expenses based on the Massachusetts Child Support Guidelines.

Income Shares Model Free & Instant 2025 Guidelines
Updated 2025 — Massachusetts Child Support Guidelines

Massachusetts Child Support Calculator

Uses the Massachusetts Income Shares model — combined gross income


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Massachusetts Guideline Child Support Estimate
$0 / month
Income Shares Model — MA Guidelines
Calculation Breakdown
Payment Summary
Monthly Support$0
Annual Support$0
Weekly Equivalent$0
This estimate is based on Massachusetts child support guidelines and is for informational purposes only. Actual court-ordered support may differ. Consult a Massachusetts family law attorney for accurate calculations.

How Massachusetts Calculates Child Support

Massachusetts uses the Income Shares model for calculating child support, having switched from a percentage-of-income model in 2009. The current guidelines, last updated in 2021, govern how courts determine child support obligations by examining both parents' combined gross income and allocating costs proportionally.

The Massachusetts calculation determines each parent's gross income, combines them, and uses the Massachusetts Child Support Guidelines worksheet to find the basic support obligation. Each parent's share is proportional to their contribution to combined income. The guidelines apply to combined gross incomes up to $400,000 per year ($33,333/month), above which the court exercises discretion.

The guidelines create a rebuttable presumption that the calculated amount is correct. Courts can deviate only for specific reasons enumerated in the guidelines, and must make written findings explaining any deviation.

The 2009 Transition to Income Shares

Massachusetts' 2009 shift to Income Shares was a significant change. The prior model calculated support as a percentage of the non-custodial parent's income only. The Income Shares model considers both parents' incomes, creating a more equitable approach. Under the current system, the custodial parent's income share is considered their contribution through direct care, while the non-custodial parent's share is paid as child support.

The Massachusetts guidelines also have specific provisions for children over 18 who are still dependents (attending college), health insurance costs, childcare expenses, and the treatment of overtime and secondary employment income. The guidelines recognize that the cost of raising children increases with income but at a decreasing rate.

The Massachusetts Guidelines Framework

The Massachusetts Child Support Guidelines are established by the Trial Court and approved by the Chief Justice for Administration and Management. They are reviewed and updated every four years as required by federal law. Key provisions include:

  • Income definition: Gross income from all sources including wages, self-employment, investments, and benefits
  • Deductions: Taxes, FICA, mandatory retirement, health insurance, prior child support, and union dues
  • Guidelines worksheet: Correlates combined income with support obligations by number of children
  • Parenting time adjustments: Adjustments for shared custody (1/3+ time each parent)
  • Age-based adjustments: Special considerations for children over 18 still dependent
  • Income cap: Guidelines apply up to $400,000 combined annual gross income

Income Definition for Massachusetts Child Support

  • Wages, salaries, tips, commissions, bonuses
  • Self-employment income
  • Social Security, pensions, disability
  • Workers' compensation, unemployment
  • Interest, dividends, rental income
  • Trust income, capital gains
  • Alimony/spousal support received
  • Military pay and allowances
Massachusetts Child Support Formula
Each Parent's Share = (Income / Combined Income) x Basic Obligation

Plus proportional shares of health insurance, childcare, and dental/vision costs

Combined Monthly Income 1 Child 2 Children 3 Children 4 Children 5 Children
$800$185$280$325$355$380
$1,500$290$440$511$559$598
$2,500$423$642$746$816$873
$3,500$534$810$941$1,030$1,102
$5,000$674$1,023$1,189$1,301$1,392
$7,000$832$1,263$1,468$1,606$1,718
$10,000$1,064$1,615$1,877$2,055$2,199
$12,500$1,236$1,877$2,181$2,387$2,554
$15,000$1,385$2,103$2,444$2,675$2,862
$20,000$1,642$2,493$2,897$3,172$3,394

Note: Simplified excerpt. The actual MA guidelines worksheet uses detailed income brackets up to $400,000/year combined.

Shared Custody in Massachusetts

Massachusetts provides for shared custody adjustments when each parent has the children approximately one-third or more of the time. The guidelines apply a 1.5 multiplier to the basic obligation and calculate each parent's share, which are then offset. The parent with the higher obligation pays the difference.

Deviations from Massachusetts Guidelines

Courts may deviate for extraordinary medical expenses, educational costs, travel expenses, income above the cap, special needs, and agreements between parents. Written findings are required.

Modifying Massachusetts Child Support

Massachusetts allows modification upon showing a material and substantial change in circumstances, or if the existing order is inconsistent with the current guidelines. No specific percentage threshold is required. File a Complaint for Modification in the Probate and Family Court. The Massachusetts DOR Child Support Enforcement Division can assist.

Enforcement

Massachusetts enforces through the Department of Revenue (DOR) Child Support Enforcement Division. Tools include income withholding, tax interception, license suspension, contempt, property liens, credit reporting, passport denial, and insurance settlement interception.

Taxes

Child support is neither taxable to the recipient nor deductible by the payer under federal and Massachusetts law. Massachusetts has no special state-level tax treatment for child support. Dependency exemptions follow federal rules.

Frequently Asked Questions

How does Massachusetts calculate child support?
Massachusetts uses the Income Shares model (since 2009). Both parents' gross incomes are combined and used to look up the basic obligation. Each parent pays proportionally. Health insurance and childcare are added and split based on income shares.
When did Massachusetts switch to Income Shares?
Massachusetts switched from a percentage-of-income model to the Income Shares model in 2009. The current guidelines were last updated in 2021 and apply to combined incomes up to $400,000 per year.
How does shared custody affect MA child support?
When each parent has the children one-third or more of the time, a shared custody formula applies with a 1.5 multiplier. Each parent's share is offset, and the higher-earning parent pays the difference.
What income counts for MA child support?
Gross income from all sources including wages, self-employment, investments, benefits, and alimony received. Deductions include taxes, FICA, mandatory retirement, health insurance, and prior support obligations.
How do I modify child support in Massachusetts?
File a Complaint for Modification in Probate and Family Court. Show a material and substantial change in circumstances, or that the current order differs significantly from current guidelines.
Until what age is child support paid in MA?
Until age 18, or 21 if the child is domiciled with a parent and enrolled in an undergraduate program. Support may also continue for a child with disabilities.
What happens if a parent does not pay in MA?
The DOR enforces through income withholding, tax interception, license suspension, contempt, liens, credit reporting, and passport denial. Massachusetts can also intercept lottery winnings.

Other State Child Support Calculators

Child support laws vary significantly from state to state. If you need to calculate child support for a different state, use one of our other state-specific calculators:

Legal Disclaimer: This calculator provides estimates based on Massachusetts child support guidelines and is for informational purposes only. It does not constitute legal advice and should not be relied upon for legal decisions. Child support calculations involve many factors that this simplified calculator cannot fully account for. Always consult with a qualified Massachusetts family law attorney for accurate child support calculations. Fine Content Limited is not a law firm and does not provide legal services.