Key takeaways
- CT-3-S pays a fixed dollar minimum of $25 to $4,500 set by New York receipts, not total receipts.
- NYC-4S is a General Corporation Tax return with a minimum from $25 to $5,000, set by City receipts.
- The CT-3-S extension is Form CT-5.4. Form CT-6 is the New York S election and extends nothing.
- For calendar 2026 returns, expect March 15, 2027 for Form 1120-S and CT-3-S, and confirm the NYC-4S date against the 2026 instructions.
Which filings a New York S corporation owes
A federal S corporation files Form 1120-S with the IRS. New York needs its own election: the Department's 2025 instructions say the corporation must file Form CT-6 and receive approval before filing Form CT-3-S. Until that approval is in hand, CT-3-S is the wrong return.
Watch for mandated status. Under the 2025 instructions, shareholders are deemed to have made the New York election when the corporation's investment income is more than 50% of its federal gross income for the year. Investment income includes interest, dividends, royalties, annuities, rents and gains from dealings in property. A holding company with a rental building and a brokerage account is the case to test.
New York City has a separate return. Form NYC-4S is the General Corporation Tax return, filed only by S corporations and qualified subchapter S subsidiaries. C corporations file Form NYC-2, NYC-2S or NYC-2A.
The state minimum counts New York receipts
CT-3-S pays the fixed dollar minimum tax under § 210.1(d), which is set by New York receipts, not income. The 2025 instructions give this table for New York S corporations, other than qualified manufacturers and emerging technology companies. Not more than $100,000 carries $25. More than $100,000 but not over $250,000 carries $50. More than $250,000 but not over $500,000 carries $175. More than $500,000 but not over $1,000,000 carries $300. More than $1,000,000 but not over $5,000,000 carries $1,000. More than $5,000,000 but not over $25,000,000 carries $3,000. Over $25,000,000 carries $4,500.
The bracket uses New York receipts, the numerator of the business apportionment factor reported in Part 3, line 57, column A. Total receipts are the wrong base. An S corporation with $1,400,000 of total receipts and $240,000 of New York receipts is in the $50 bracket. Using total receipts would put the same corporation in the $1,000 bracket.
For a short year, divide New York receipts by the number of months, multiply by 12, find the bracket, then reduce the tax by 50% for six months or less, or by 25% for more than six months and not more than nine months. Example: a six-month short year with $100,000 of New York receipts annualizes to $200,000 and carries $50. The 50% reduction leaves $25.
These figures come from the 2025 instructions. The 2026 CT-3-S instructions were not posted at the Department's 2026 address when checked, so confirm the table before paying. The 2025 instructions allow the 2025 form for a 2026 year when the 2026 form is not yet available.
NYC-4S: pick the form, then the City minimum
NYC-4S applies to S corporations. Work the forms in this order. First, NYC-3L applies if the corporation carries on business both inside and outside the City, has subsidiary or investment capital, claims a credit, or adds back pass-through entity taxes when calculating entire net income. Taxpayers filing NYC-4S may not claim any tax credits.
Second, NYC-4S-EZ applies only if all four tests pass: a 100% business allocation for the year; no investment or subsidiary capital or income at any time in the year; federal gross income under Internal Revenue Code section 61 below $250,000, taken from the federal gross income line rather than receipts; and no change to the federal depreciation deduction on Forms NYC-399 and NYC-399Z.
Otherwise the corporation files NYC-4S. Its City receipts are all receipts in the regular course of business, because it allocates 100 percent of income to the City. The 2025 City table: not more than $100,000 carries $25. More than $100,000 but not over $250,000 carries $75. More than $250,000 but not over $500,000 carries $175. More than $500,000 but not over $1,000,000 carries $500. More than $1,000,000 but not over $5,000,000 carries $1,500. More than $5,000,000 but not over $25,000,000 carries $3,500. Over $25,000,000 carries $5,000.
For NYC-4S-EZ filers, the instructions say the tax is the greater of the entire net income base or the fixed dollar minimum, so a loss year still pays the minimum. Example: $620,000 of City receipts falls in the $500 bracket.
Deadlines and extensions for tax year 2026
Federal Form 1120-S is due by the 15th day of the third month after the tax year ends. For calendar 2026 that is March 15, 2027. The 2025 return was due March 16, 2026, because March 15, 2026 fell on a Sunday. Form 7004 gives an automatic six-month extension.
New York CT-3-S is due on or before March 15 for calendar-year filers. The extension is Form CT-5.4, Request for Six-Month Extension to File New York S Corporation Franchise Tax Return. It must be filed, with the properly estimated franchise tax paid, by the original due date. Most corporations file it electronically. Interest on any underpayment runs from the original due date, regardless of the extension.
Form CT-6 is not an extension. Note it in the file as “CT-6 election, approval required before CT-3-S.” A late CT-3-S carries a charge of 5% per month, up to 25% of the tax.
New York City NYC-4S was due March 16, 2026 for calendar 2025 returns. For calendar 2026, expect March 15, 2027, pending the 2026 instructions. Form NYC-EXT gives a six-month automatic extension if it is filed by the due date with the properly estimated tax paid. Form NYC-EXT.1 adds up to two three-month extensions.
CT-3-S document checklist
Get the Department's CT-6 approval, the federal Form 1120-S as filed or in final draft, and the Schedule K-1 (Form 1120-S) for every shareholder. Form CT-34-SH must be attached to CT-3-S, and it reports each shareholder's pro rata share of the S corporation items.
For each shareholder, get the name, address, percentage owned and Social Security number. The instructions set a $50 penalty for each shareholder whose Social Security number is not shown. Also get the New York receipts figure for Part 3, line 57, column A, tied to the books.
For estimated tax, get the payments made, any Form CT-400, and whether a liability above $1,000 required Form CT-222. Check Form IT-2658 for nonresident individual shareholders and Form CT-399 for depreciation differences. In a termination year, the S short year goes on CT-3-S and the C short year on Form CT-3, with the same due date.
NYC-4S document checklist
Get total receipts by source: sales of personal property, services performed, rentals and royalties. Tie the total to the books and the federal return before choosing the bracket.
A federal S corporation must complete Form NYC-ATT-S-CORP and include it with the GCT filing. For the EZ test, keep the allocation, capital, gross income and depreciation support for Forms NYC-399 and NYC-399Z.
If the corporation claims a net operating loss deduction, attach Form NYC-NOLD-GCT. If expected City tax for the following period exceeds $1,000, file Form NYC-400. Keep the Form NYC-200V voucher and proof of the postmark.
Failure modes and how to fix them
Wrong receipts base. CT-3-S uses New York receipts and NYC-4S uses all receipts. Putting total receipts on the state return moves the example client from the $50 bracket to the $1,000 bracket.
Extension on the wrong form. CT-6 extends nothing. Use CT-5.4 for the state, NYC-EXT for the City and Form 7004 for the 1120-S. A state return more than 60 days late carries a charge of at least the smaller of $100 or 100% of the tax, and the City has the same floor.
Missing shareholder data. The state penalty is $50 per shareholder per month, up to $250 per shareholder, for late shareholder information, plus $50 for each missing Social Security number.