Schedule 4% Surtax: 4% Surtax on Taxable Income Over $1 Million (2025)
Massachusetts · Massachusetts DOR · Used for tax years 2025
Massachusetts Schedule 4% Surtax calculates the 4% surtax on income above the 2025 threshold of $1,083,150. It combines amounts from your return and related schedules to determine the surtax to report on your return.
Who files this form
The 2025 Schedule 4% Surtax is for filers of Massachusetts Form 1, Form 1-NR/PY, Form 2, Form M-990T-62, and Form 3M.
Combine the income amounts entered on lines 1 through 3. If the total is less than $1,083,150, the form says the 4% surtax does not apply and you should not submit this schedule.
What you'll need
Have your taxpayer name, Social Security number or employer identification number, and the applicable return and schedules available. The schedule uses these amounts:
- Form 1: Line 19; Schedule B, line 37; and Schedule D, line 21, or Schedule D-IS, the sum of Part 3, column 1, lines 26 a-h.
- Form 1-NR/PY: Line 23; Schedule B, line 37; and Schedule D, line 21, or Schedule D-IS, the sum of Part 3, column 1, lines 26 a-h.
- Form 2: Lines 21, 29, and 37.
- Form M-990T-62: Lines 21 and 25.
- Form 3M: Line 1; Schedule B, line 27; and Schedule D, line 16.
How to file
The form directs you to enclose this schedule with your return. It does not provide a mailing address or e-filing instructions.
To complete the calculation:
- Enter the applicable return amounts on lines 1 through 3. Each amount must be at least zero.
- Combine those amounts on line 4. If the total is less than $1,083,150, do not submit the schedule.
- Enter the 2025 threshold of $1,083,150 on line 5.
- Subtract line 5 from line 4 and enter the result on line 6.
- Multiply line 6 by 0.04 (4%) and enter the result on line 7.
Also enter the line 7 amount on your return:
- Form 1: Line 28b.
- Form 1-NR/PY: Line 32b.
- Form 2: Line 41b.
- Form M-990T-62: Line 29b.
- Form 3M: Line 9b.
Common mistakes
- Entering negative amounts on lines 1 through 3. Each line says the amount must not be less than zero.
- Submitting the schedule when line 4 is below $1,083,150. The note says the surtax does not apply and not to submit the schedule.
- Forgetting to include the schedule with your return when submitting it. The form says to enclose it with your return.
Questions people ask
What is the surtax threshold for tax year 2025?
The threshold printed on line 5 is $1,083,150.
Is the 4% rate applied to the entire line 4 amount?
No. First subtract the $1,083,150 threshold from line 4. Then multiply the result by 4%.
Should I submit this schedule if line 4 is below the threshold?
No. The form says that if line 4 is less than $1,083,150, the surtax does not apply and you should not submit the schedule.
Where does the calculated surtax go?
Enter it on Schedule 4% Surtax, line 7, and on the applicable return: Form 1, line 28b; Form 1-NR/PY, line 32b; Form 2, line 41b; Form M-990T-62, line 29b; or Form 3M, line 9b.