This Massachusetts Child Support Calculator is for child support orders in MA from October 4, 2021 through November 30, 2025.
For filings and child support orders for December 1, 2025 and later, you must use this 2025-2026 Child support calculator.
This Massachusetts child support calculator illustrates post-tax income after child support is calculated.
The August 2022 MA Supreme Judicial Court ruling in Cavanagh v. Cavanagh says that judges making orders in contested (1B) cases must look not only at the result of this child support calculation, but also at child support calculations that first calculate alimony, then use the post-alimony-calculation incomes to then calculate child support.
A unique Cavanagh alimony, child support, and taxes calculator for Massachusetts divorce on this site does the calculations that judges must consider when making orders in contested (1B) divorce cases that could involve child support.
I mediate MA divorces for Worcester, Boston, Springfield, and all MA locations with online divorce mediation on Zoom. Please feel free to contact me with any questions you have about divorce mediation or uncontested divorce. You can try the most user-friendly MA alimony calculator here.
To calculate how much child support you should pay or receive for court orders between October 4, 2021 and November 30, 2025, simply fill in the following information and click “Calculate”.
| Gross Annual Income | ||
| Approximate Annual MA and Federal Taxes | ||
| Annual Child Support | ||
| Approximate annual income after taxes and child support |
Your guidelines child support amount is .
Enter a different support amount here, and click the CALCULATE button:
| Gross Annual Income | ||
| Approximate Annual MA and Federal Taxes | ||
| Annual Non-guideline Support Amount Chosen by User | ||
| Approximate annual income after taxes and non-guideline support amount chosen by user |
Tax calculation formulas come from the 2025-2026 calculator at: https://goodcalculators.com/us-salary-tax-calculator/massachusetts/
If a parent has the child(ren) 67% of the time, that parent’s taxes are calculated as "Head of household" and the other parent’s taxes are calculated as "Single". If parenting time is 50-50, this calculator treats both parents as filing "Single".
This tax calculator is most accurate for salaried employees who take the standard deduction and who have low pre-tax deductions on their paystub. It will be less accurate on tax calculations for people who make significant 401k contributions, are self-employed, have their own business, have rental income, have investment income, etc.
This calculator does not include the Child Tax Credit, for children who are 17 or younger at the end of the tax year. These tax credits can be taken by either parent. The separation agreement should specify which parent takes which credits in which years. The amount of this credit was set at $2200 in 2025 federal legislation.
This calculator does not include any Child and Dependent Care Tax Credit, and it does not include any Earned Income Tax Credit (for low- to moderate-income families).