MA Income Tax

Massachusetts Individual Income Tax Skill — Self-Employed / Sole Proprietor

Scope. This skill covers Massachusetts Form 1 (Resident Income Tax Return) for sole proprietors and single-member LLCs. It addresses the flat 5% income tax, the 4% millionaire's surtax, and Massachusetts-specific income classifications. It does NOT cover nonresident/part-year returns (Form 1-NR/PY), corporate excise (Form 355), or trust/estate returns (Form 2).

Quality tier. Q3 — AI-drafted, not independently verified. All outputs must be reviewed by a qualified tax professional before filing.

Section 1: Metadata

Metadata

Field	Value
Jurisdiction	Massachusetts (US-MA)
Tax authority	Massachusetts Department of Revenue (DOR)
Filing portal	MassTaxConnect
Legislation	M.G.L. Chapter 62 — Taxation of Incomes
Primary form	Form 1 (Massachusetts Resident Income Tax Return)
Filing deadline	April 15, 2027 (for tax year 2026)
Version	0.1
Date	May 22, 2026
Validation status	AI-drafted — Q3

Sources consulted

1. Massachusetts DOR — Tax Rates: https://www.mass.gov/service-details/tax-rates
2. Massachusetts DOR — Personal Income Tax for Residents: https://www.mass.gov/guides/personal-income-tax-for-residents
3. Massachusetts DOR — 4% Surtax on Taxable Income: https://www.mass.gov/info-details/4-surtax-on-taxable-income-over-1000000
4. M.G.L. c. 62, §§ 4, 5, 5A
5. Article 44 of the Massachusetts Constitution (as amended by 2022 ballot question — "Fair Share Amendment")

Section 2: Quick reference — rates and thresholds

Income tax rates

Income tax rates

Income type	Rate	Source
Part A income (interest, dividends, capital gains from non-MA obligations)	5.00%	M.G.L. c. 62, § 4(a)
Part B income (wages, salaries, self-employment, most other income)	5.00%	M.G.L. c. 62, § 4(b)
Part C income (short-term capital gains)	8.50% (subject to 50% deduction, effective rate ~12%)	M.G.L. c. 62, § 4(c)
Long-term capital gains	5.00%	M.G.L. c. 62, § 4(b)

Millionaire's surtax (4% additional tax)

Millionaire's surtax thresholds

Tax year	Surtax threshold	Source
2023	$1,000,000	Article 44
2024	$1,053,750	Inflation-adjusted
2025	$1,083,150	Inflation-adjusted
2026	TBD (inflation-adjusted, typically announced late in preceding year)	M.G.L. c. 62, § 5A

• Surtax application — The 4% surtax applies only to the portion of taxable income exceeding the threshold. For a taxpayer with $1,100,000 in TY2025 taxable income, the surtax applies to $16,850 ($1,100,000 − $1,083,150). (M.G.L. c. 62, § 5A)

Deductions and exemptions

Massachusetts does not use a standard deduction in the federal sense. Instead, it provides:

Deductions and exemptions table

Item	Amount (TY2025)	Source
Personal exemption — Single	$4,400	M.G.L. c. 62, § 3(B)(a)
Personal exemption — Head of Household	$6,800	M.G.L. c. 62, § 3(B)(b)(2)
Personal exemption — MFJ	$8,800	M.G.L. c. 62, § 3(B)(b)(1)
Dependent deduction	$1,000 per dependent	M.G.L. c. 62, § 3(B)(a)(3)
Rental deduction	50% of rent paid, max $3,000	M.G.L. c. 62, § 3(B)(a)(9)

Filing threshold

• Filing threshold — $8,000 of Massachusetts gross income USD (Everyone whose Massachusetts gross income is $8,000 or more must file.)

Section 3: How this skill works with the federal return

Starting point

• Income classification system — Massachusetts uses its own income classification system rather than starting directly from federal AGI. However, the computation references federal Form 1040 amounts extensively. Massachusetts income is divided into three parts: - Part A: Interest, dividends, and net capital gains on non-Massachusetts obligations - Part B: Wages, salaries, self-employment income, pensions, annuities, and most other income - Part C: Short-term capital gains and gains on collectibles

Key differences from federal

Key differences from federal table

Item	Massachusetts treatment	Source
No standard deduction	MA uses personal exemptions and specific deductions instead	M.G.L. c. 62, § 3
Social Security	Fully exempt	M.G.L. c. 62, § 2(a)(2)(E)
Interest from MA obligations	Exempt	M.G.L. c. 62, § 2
Interest from other states	Taxable (add back any federal exclusions)	M.G.L. c. 62, § 2
Short-term capital gains	Taxed at 8.50% (not the standard 5%)	M.G.L. c. 62, § 4(c)

Resulting computation

• Computation order — Compute Part A, Part B, and Part C income separately → subtract applicable deductions and exemptions → apply the appropriate rate to each part → sum = Massachusetts gross tax → minus credits → plus 4% surtax if applicable.

Section 4: Self-employed specific rules

Estimated tax payments

• Estimated tax payment obligation — Self-employed individuals must make quarterly estimated tax payments if they expect to owe $400 or more.

Estimated tax payment due dates

Voucher	Due date
1st quarter	April 15
2nd quarter	June 15
3rd quarter	September 15
4th quarter	January 15 (following year)

Use Form 1-ES for estimated payments.

Self-employment health insurance

• Self-employment health insurance — Massachusetts generally follows federal treatment — the deduction is taken as a Part B deduction.

Retirement contributions (SEP, SIMPLE, Solo 401(k))

• Retirement contributions — Massachusetts generally follows federal treatment — these deductions reduce Part B income.

Home office deduction

• Home office deduction — Massachusetts follows the federal home office deduction as part of Schedule C.

QBI deduction (Section 199A)

• QBI deduction disallowed — Massachusetts does not allow the federal QBI deduction. Massachusetts has its own income computation that does not incorporate the QBI deduction.

Health insurance mandate

• Health insurance mandate — Massachusetts has an individual health insurance mandate (separate from the ACA). Failure to maintain minimum creditable coverage may result in a penalty assessed on Form 1 (Schedule HC). This is relevant for self-employed individuals who must obtain their own coverage.

Section 5: Tier 1 rules — deterministic

Tier 1 rules table

Rule	Description
R-1	Apply 5% to Part A and Part B income. Apply 8.50% to Part C (short-term capital gains).
R-2	Apply the 4% surtax on total taxable income exceeding the inflation-adjusted threshold ($1,083,150 for TY2025).
R-3	Social Security is fully exempt.
R-4	Interest from U.S. obligations is exempt.
R-5	Interest from Massachusetts municipal bonds is exempt; interest from other states' bonds is taxable.
R-6	Massachusetts does NOT have a standard deduction — use the personal exemption system.
R-7	Long-term capital gains are taxed at 5%, NOT the short-term rate.
R-8	Massachusetts has NO local/county income taxes. Only the state tax applies.
R-9	Filing threshold: $8,000 of MA gross income.

Section 6: Tier 2 rules — requires judgment

Tier 2 rules table

Rule	Description
J-1	Classify income correctly among Part A, Part B, and Part C — misclassification changes the rate.
J-2	Determine whether the taxpayer's total income approaches the surtax threshold and whether income timing strategies are appropriate.
J-3	Evaluate Massachusetts deductions vs. federal deductions (they differ significantly).
J-4	Assess the health insurance mandate penalty when the taxpayer had gaps in coverage (Schedule HC).
J-5	Determine credit for taxes paid to other states for multi-state income.

Section 7: Supplier pattern library

Supplier pattern library table

Pattern	Massachusetts treatment
Freelance income (Schedule C)	Part B income. Taxed at 5%.
Rental income (Schedule E)	Part B income. Taxed at 5%.
Short-term capital gains	Part C income. Taxed at 8.50%.
Long-term capital gains	Part B income. Taxed at 5%.
Interest / dividends	Part A income. Taxed at 5%. MA and U.S. obligations exempt.
Social Security	Fully exempt.
Pension / retirement	Part B income. Taxed at 5%.

Section 8: Form mapping

Form 1 line mapping table

Form 1 line	Description	Source
Lines 1–4	Part A income (interest, dividends)	M.G.L. c. 62, § 2
Lines 5–10	Part A deductions and exemptions	M.G.L. c. 62, § 3
Line 10	Part A taxable income	Computed
Lines 11–14	Part B income (wages, self-employment, pensions)	M.G.L. c. 62, § 2
Lines 15–20	Part B deductions and exemptions	M.G.L. c. 62, § 3
Line 20	Part B taxable income	Computed
Line 21	Part C income (short-term capital gains)	M.G.L. c. 62, § 2
Line 23	Total 5% income tax (Part A + Part B at 5%)	Computed
Line 24	8.50% tax on Part C	Computed
Line 25	Total income tax before credits	Sum
Line 28	Credits	Various
Line 29	4% surtax (if applicable)	M.G.L. c. 62, § 5A
Lines 34–39	Payments, withholding, estimated payments	Various
Line 43	Balance due or refund	Computed

Section 9: Refusal catalogue

Refusal catalogue table

Code	Situation	Action
REF-MA-01	Taxpayer is a nonresident or part-year resident	Refuse; requires Form 1-NR/PY.
REF-MA-02	Taxpayer has complex Part A / Part B / Part C classification issues	Flag for reviewer.
REF-MA-03	Taxpayer's income exceeds the surtax threshold and involves timing strategies	Flag for reviewer — surtax cliff analysis needed.
REF-MA-04	Taxpayer claims complex credits (e.g., Brownfields, Life Sciences, Film)	Flag for reviewer.
REF-MA-05	Taxpayer has Schedule HC penalty issues (gaps in health insurance coverage)	Flag for reviewer — penalty computation is complex.

Disclaimer

This skill and its outputs are provided for informational and computational purposes only and do not constitute tax, legal, or financial advice. Open Accountants and its contributors accept no liability for any errors, omissions, or outcomes arising from the use of this skill. All outputs must be reviewed and signed off by a qualified professional before filing or acting upon.

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