Massachusetts 4% Millionaire Surtax (Article 44): Tax Brackets, Capital Gains & Wealth Migration Audit
Quantitative analysis of Massachusetts's 4% Fair Share Amendment surtax on income above $1.08M+. How the 9.0% long-term and 12.5% short-term rate works, filing status strategies, and New Hampshire domicile outflows.
By Pablo Cirre Gómez and East Corp Capital Quantitative Desk
NEW YORK — Sit down at a kitchen table anywhere from Manhattan and Westchester to Bergen County, Fairfield County, or Back Bay Boston, and one financial question quickly dominates the conversation around massachusetts 4% millionaire surtax (article 44): How do the 2026 statutory rules, interest rates, and regional tax brackets actually translate into real dollars for your household or business? Under Article 44 of the Massachusetts Constitution (the ‘Fair Share Amendment’), taxable income exceeding the inflation-adjusted $1 million threshold ($1,083,150+ in 2025/2026) faces an additional 4.0% surtax on top of the flat 5.0% base rate.
Federal & East Coast State Capital Gains + 3.8% NIIT Calculator
Calculates combined Federal long/short-term capital gains tax, the 3.8% Net Investment Income Tax, and state surtaxes (including NYC 14.776% and Mass. 9% Millionaire Tax).
How Does The Married Filing Separately (MFS) Arbitrage under Massachusetts Law Impact Your Bottom Line?
When Massachusetts voters approved Article 44, the constitutional text levied the 4% surtax on annual taxable income above $1,000,000 (indexed annually for CPI inflation) per return, without creating a separate halved threshold for Married Filing Separately filers. Subsequently, Massachusetts statutory updates required spouses who file a joint federal return to generally file a joint Massachusetts return—except in specific non-resident or domicile-split scenarios, or when couples elect Married Filing Separately at both the federal and state levels.
For two-earner Boston or Newton households where each spouse earns $950,000 ($1.9M combined), modeling whether the federal cost of filing Married Filing Separately is smaller than the $32,600+ Massachusetts 4% surtax savings is now an essential autumn CPA exercise.
| Income Category | Rate Below Threshold (~$1.08M) | Surtax Rate Above Threshold | Total Combined MA Rate | Combined w/ Federal + 3.8% NIIT |
|---|---|---|---|---|
| W-2 Wages & Pass-Through Business Income | 5.00% | +4.00% | 9.00% | 46.0% – 49.8% |
| Long-Term Capital Gains (> 1 Year) | 5.00% | +4.00% | 9.00% | 32.80% |
| Short-Term Capital Gains (≤ 1 Year) | 8.50% | +4.00% | 12.50% | 53.30% |
| Collectibles & Certain Pre-1996 Gains | 12.00% | +4.00% | 16.00% | 47.80% |
Let’s Run the Numbers in Dollars: Comparing W-2 Wages & Pass-Through Business Income vs. Short-Term Capital Gains (≤ 1 Year) in the Tri-State Corridor
Let’s run the numbers in dollars using verified 2026 benchmarks from our quantitative table above so you can see the exact gap before making a decision:
- Baseline Profile (Income Category: W-2 Wages & Pass-Through Business Income): Produces a verified outcome of 46.0% – 49.8% (Combined w/ Federal + 3.8% NIIT), reflecting 5.00% and +4.00%.
- Scaled Tri-State Profile (Income Category: Short-Term Capital Gains (≤ 1 Year)): Shifts the net figure to 53.30% (Combined w/ Federal + 3.8% NIIT). This pushes the top Massachusetts marginal rate to 9.0% on wages and long-term capital gains, and to 12.5% on short-term capital gains (8.5% base + 4.0% surtax).
How Does Installment Sales (IRC § 453) to Smooth Business Exit Gains Below $1.08M Impact Your Bottom Line?
Because the 4% surtax is triggered annually based on realized Massachusetts taxable income, founders selling a lower-middle-market business for $3.5 million in a single cash closing lose 4% on the $2.42 million above the threshold ($96,800 extra tax). Structuring the transaction as a 4-year installment note under IRC § 453 keeps annual recognized gain under $1.08 million per year, legally eliminating the 4% surtax on the entire exit.
To model how this interacts with the rest of your East Coast balance sheet, run your numbers in our NYC & NY State Paycheck Tax Calculator, compare housing and closing tax rules in our NYC Mansion Tax & Closing Cost Calculator, and benchmark after-tax fixed-income yields in our US Treasury Bills vs. Bank CDs Calculator.
Frequently Asked Questions
Does the Massachusetts 4% Millionaire Surtax apply to non-residents selling Massachusetts real estate?
Yes. Non-residents are subject to the 4% surtax to the extent their Massachusetts-source taxable income (such as the capital gain from selling a vacation home on Nantucket, Martha's Vineyard, or the Cape, or MA business income) exceeds the annual inflation-adjusted surtax threshold.
How close is Southern New Hampshire for Boston commuters seeking 0% income tax?
Towns in Rockingham and Hillsborough counties in Southern New Hampshire (such as Bedford, Windham, Hollis, and Portsmouth) are 40 to 55 minutes from northern Greater Boston tech corridors. New Hampshire levies 0% tax on W-2 wages and capital gains (and fully phased out its Interest & Dividends tax in 2025), though NH residents who physically commute into a Boston office still owe MA non-resident tax on their MA-worked days.