355S: S Corporation Excise Return (2025)
Massachusetts · Massachusetts DOR · Used for tax years 2025
Form 355S is the Massachusetts S Corporation Excise Return for 2025. It reports income, taxable tangible property or net worth, credits and payments to calculate the corporation’s excise due or overpayment. The return must be filed electronically; paper returns are not accepted.
What you'll need
Have the information requested on the form ready:
- Corporation name, federal identification number (FID), business addresses and principal business code from the U.S. return.
- Massachusetts and worldwide employee counts.
- Balance sheet information for Schedule A, including assets, depreciation and amortization, liabilities and capital.
- U.S. Form 1120 figures referenced in Schedule E.
- Prior-year overpayments applied to this year, estimated tax payments, extension payments and applicable withholding and credit amounts.
Depending on the entries you report, supporting forms and schedules include:
- Form AA-1 if requesting alternative apportionment.
- The Credit Recapture Schedule if reporting credit recapture.
- The Credit Manager Schedule for credits and refundable credits.
- Schedule 63-WH for corporate excise withheld.
- Schedule ABIE or ABI for exceptions to intangible or interest expense add-backs.
- Schedule NOL for a net operating loss deduction.
- A schedule showing dividend payers, amounts and the percentage of voting stock owned by class of stock for Schedule E-1.
How to file
File electronically. The form states that paper returns will not be accepted. Do not mail a paper Form 355S.
For questions about electronic filing, call 617-887-6367. See the Massachusetts Department of Revenue's electronic filing and payment requirements for more information.
The return includes a declaration that the return and enclosures are true, correct and complete, and requests the signature of an appropriate officer.
Common mistakes
- Sending a paper return: Form 355S is e-file only. Paper returns will not be accepted.
- Prorating the minimum excise: The form says the minimum excise cannot be prorated.
- Counting a prior-year overpayment twice: Do not include the amount on line 17 again in estimated tax payments on line 18.
- Using line 20 on an original return: This line is only for reporting payment with the original return when amending a return.
- Leaving Schedule A unfinished: The form reminds filers to continue Schedule A on its second page.
- Entering a negative amount where prohibited: Follow the form's instructions not to enter less than zero, including on excise calculation line 5 and Schedule A line 33.
Questions people ask
What tax-year dates should a calendar-year filer enter?
For the 2025 return, enter 01-01-2025 as the beginning date and 12-31-2025 as the ending date. Fiscal-year filers enter their appropriate dates. These are tax-period dates, not filing deadlines.
Should I complete Schedule C or Schedule D?
Complete Schedule C if Schedule B, line 15 is 10% or more. Complete Schedule D if that percentage is less than 10%. Both schedules direct you to use net book values from Schedule A, column c.
Can I apply an overpayment to next year?
Yes. Enter the amount to credit to next year on line 25. Line 26 shows the refund amount after subtracting line 25 from the overpayment on line 24.
Does the return ask about digital assets?
Yes. Line 18 asks whether, at any time during the year, the corporation received a digital asset as a reward or payment for property or services, or sold, exchanged or otherwise disposed of a digital asset or a financial interest in one.