2026 Massachusetts State Tax Deadlines
Massachusetts Individual income tax filing deadlines and extensions for 2026
If you are a resident or have been involved in business operations within Massachusetts, you might be required to file Massachusetts State taxes. Massachusetts follows a flat income tax structure with a 5% rate (plus 4% surtax on income over $1 million), making it essential to understand the specific deadlines and requirements for 2026.
Massachusetts business tax deadlines for 2026
C Corporations' deadlines and requirements
C Corporations in Massachusetts must file and pay Corporate Excise Tax by April 15, 2027, following the federal due date schedule.
Filing requirements include:
- Complete Form 355 (Massachusetts Corporation Excise Return)
- File via MassTaxConnect
- Payment must be made by April 15, 2027
- Mail submissions must be postmarked by the due date
Extension to file taxes in Massachusetts for 2026
The Extension Deadline for Massachusetts Corporate excise tax returns is October 15, 2027. Massachusetts automatically grants a six-month extension following the federal extension timeline without requiring separate forms. This is an extension to FILE, not an extension to PAY—payment is still due April 15, 2027.
Pass-through entities
Massachusetts S Corporations and Partnerships tax deadlines for 2026
S Corporations and Partnerships must file in Massachusetts by March 15, 2027.
Required forms include:
- Form 355S—S Corporation Return
- Form 3—Partnership Return
Extension to file S Corporations and Partnerships taxes in Massachusetts for 2026
The Extension Deadline for Massachusetts S Corporations and Partnerships returns is September 15, 2027. Massachusetts automatically grants a six-month extension without requiring separate applications. This is an extension to FILE, not an extension to PAY—payment is still due March 15, 2027.
Massachusetts Individual tax considerations for 2026
Filing requirements and income thresholds
Massachusetts Individuals must file a State income tax return if their gross income exceeds specific thresholds based on filing status.
The tax rates for 2026 are:
- 5% on all Massachusetts taxable income
- 4% additional surtax on income over $1 million (total 9% on income over $1 million)
Estimated tax deadline for Massachusetts 2026
Estimated tax payments are due on the following schedule for calendar year filers:
- April 15, 2026
- June 15, 2026
- September 15, 2026
- January 15, 2027
Who must make estimated payments
You must make Massachusetts estimated income tax payments during 2026 if you expect to owe a significant amount in Massachusetts income tax after subtracting withholding and credits. The millionaire's surtax requires special attention for high-income taxpayers.
Individual tax deadline for Massachusetts 2026
Individual income tax returns are due April 15, 2027.
Available forms include:
- Form 1—Massachusetts Resident Individual Income Tax Return
- Form 1-NR/PY—Massachusetts Nonresident or Part-Year Resident Individual Income Tax Return
Extension to file taxes in Massachusetts for 2026
The Extension Deadline is October 15, 2027, to file your Massachusetts Individual Income tax return. Massachusetts automatically grants a six-month extension without requiring separate extension forms. This is an extension to FILE, not an extension to PAY—payment is still due April 15, 2027.
What Massachusetts tax professionals need to know
Several key considerations make Massachusetts's tax landscape unique for 2026. Massachusetts's flat income tax system includes a substantial surtax on high-income earners, resulting in some of the highest effective tax rates in New England. Electronic filing requirements continue to expand, and Massachusetts provides specific tax planning opportunities despite the high-tax environment.
Electronic filing requirements
Massachusetts has implemented electronic filing systems for taxpayers:
- C Corporations and pass-through entities should file electronically through MassTaxConnect
- Individuals can use Massachusetts's online system for free electronic filing
- Business deductions can be processed more efficiently through electronic systems
- Professional preparers must use approved software vendors
Unique Massachusetts tax features for 2026
Massachusetts offers several distinctive tax features, including:
- 5% flat rate with 4% surtax on income over $1 million
- No sales tax on necessities like clothing under $175 and groceries
- Earned Income Credit available to eligible taxpayers
- Limited deduction for federal taxes paid
Millionaire's Surtax
Massachusetts's 4% surtax on income over $1 million creates specific planning considerations:
- Applies to Individuals with Massachusetts taxable income over $1 million
- Creates 9% effective rate on high-income earners
- Important for the timing of income and deductions
- May influence residency planning decisions
High-Income Tax Planning
Massachusetts's high effective rates for wealthy taxpayers create opportunities:
- Income timing strategies around the $1 million threshold
- Multi-state tax planning for high earners
- Investment structure planning
- Charitable giving strategies to reduce taxable income
Technology and Life Sciences Focus
Massachusetts's economy emphasizes technology and life sciences:
- Research and development tax credits
- Life sciences tax incentives
- Investment tax credits for specific industries
- Brownfields redevelopment credits
Business incentives and credits
Massachusetts provides various business tax incentives:
- Investment Tax Credit
- Research Credit
- Economic Development Incentive Program (EDIP)
- Life Sciences Tax Incentives
- Film Production Credit
Higher Education Considerations
Massachusetts has numerous colleges and universities:
- Educational institution tax exemptions
- Student loan interest considerations
- Tuition and fees deductions
- Special provisions for educational employees
Retirement income considerations
Massachusetts provides certain retirement income benefits:
- Military retirement pay exemptions may apply
- Social Security benefits are generally exempt from the Massachusetts state income tax
- Pension income considerations for residents
- Senior citizen tax benefits
Healthcare Industry
Massachusetts's significant healthcare sector has special considerations:
- Healthcare-related business incentives
- Medical device tax implications
- Health insurance premium tax considerations
- Research institution provisions
Professional tax guidance
Given Massachusetts's complexity and high rates, consulting with qualified tax professionals through an accounting firm directory is especially important for Massachusetts taxpayers to ensure compliance and optimize tax planning strategies.
Sources
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The material discussed on this page is meant for general illustration and/or informational purposes only and is not to be construed as investment, tax, or legal advice. You must exercise your own independent professional judgment, recognizing that advice should not be based on unreasonable factual or legal assumptions or unreasonably rely upon representations of the client or others. Further, any advice you provide in connection with tax return preparation must comply in full with the requirements of IRS Circular 230.
Please note that if any due date falls on a federal or state holiday or weekend, it may be adjusted to the next business day. Always verify current deadlines with the appropriate tax professional and authorities.
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