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Massachusetts Business Tax Deadlines (2026)

Next: June 15, 2026 — Federal & Massachusetts Q2 Estimated Tax Payment

Next Deadline: June 15, 2026 — Federal & Massachusetts Q2 Estimated Tax Payment

Federal Tax Deadlines (2026)

FormWho FilesDue DateExtension Deadline
Form 1040 (Schedule C)Sole proprietorsApril 15October 15
Form 1065Partnerships, Multi-member LLCsMarch 15September 15
Form 1120-SS-CorporationsMarch 15September 15
Form 1120C-CorporationsApril 15October 15
Form 990NonprofitsMay 15November 15
Estimated Taxes (Q1)AllApril 15
Estimated Taxes (Q2)AllJune 15
Estimated Taxes (Q3)AllSeptember 15
Estimated Taxes (Q4)AllJanuary 15, 2027

Massachusetts State Tax Deadlines (2026)

Tax TypeDue DateForm/FilingNotes
Individual Income TaxApril 15Form 1Flat 5% + 4% millionaire's surtax
Corporate Excise TaxMarch 15 (S-corp) / April 15 (C-corp)Form 3558% rate on income
S-Corp ReturnMarch 15Form 355SPass-through
Partnership ReturnMarch 15Form 3Pass-through
Sales Tax (Monthly)20th of following monthVia MassTaxConnectState rate 6.25%
Meals Tax20th of following monthVia MassTaxConnect6.25% + optional 0.75% local
Withholding Tax (Monthly/Weekly)Varies by payrollVia MassTaxConnectEmployers
Annual ReportAnniversary of formationFiled with Secretary of Commonwealth$500 (Corp); $500 (LLC)
Estimated Income Tax (Q1)April 15Form 1-ES / 355-ES
Estimated Income Tax (Q2)June 15Form 1-ES / 355-ES
Estimated Income Tax (Q3)September 15Form 1-ES / 355-ES
Estimated Income Tax (Q4)January 15, 2027Form 1-ES / 355-ES

Quarterly Estimated Tax Deadlines in Massachusetts

Massachusetts follows the federal estimated tax payment schedule:

  • Q1: April 15, 2026
  • Q2: June 15, 2026
  • Q3: September 15, 2026
  • Q4: January 15, 2027
  • Estimated payments are required if you expect to owe $400 or more in Massachusetts income tax.

    Massachusetts-Specific Tax Requirements

    Massachusetts has a flat income tax rate of 5% for most income types. Starting in 2023, the state added a 4% "millionaire's surtax" on annual income exceeding $1 million, bringing the top effective rate to 9%. Short-term capital gains (held less than one year) are taxed at 8.5% plus the surtax if applicable. The corporate excise tax rate is 8% on net income, with an additional component based on tangible property or net worth.

    The state sales tax rate is 6.25%, with no local additions for general sales. However, some municipalities impose an optional 0.75% local meals tax on top of the state 6.25% rate. The economic nexus threshold for remote sellers is $100,000 in sales. Massachusetts exempts clothing under $175 from sales tax.

    Annual reports are filed with the Secretary of the Commonwealth. The filing fee is $500 for both corporations and LLCs — one of the highest in the country. Massachusetts has no franchise tax separate from the corporate excise tax. Employers must register for withholding and file on a schedule based on payroll (weekly, monthly, or quarterly). Massachusetts also offers an elective Pass-Through Entity Excise for S-corps and partnerships.

    What Happens If You Miss a Massachusetts Tax Deadline?

  • Late filing penalty: 1% per month of unpaid tax, up to 25%
  • Late payment penalty: 1% per month of unpaid tax (separate from filing penalty), up to 25%
  • Interest rate: Adjusted quarterly; approximately 8% per year (federal short-term rate + 4%)
  • How to file for an extension: File Form M-4868 for an automatic 6-month extension. Massachusetts also honors a filed federal extension. At least 80% of the tax liability must be paid by April 15.
  • Massachusetts Department of Revenue

  • Website: https://www.mass.gov/orgs/massachusetts-department-of-revenue
  • Phone: (617) 887-6367
  • Online Filing: https://mtc.dor.state.ma.us
  • Get Your Books Ready Before Tax Season

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