CT-13: Unrelated Business Income Tax Return (2025)
New York · NY DTF · Used for tax years 2025
Form CT-13 is New York’s Unrelated Business Income Tax Return under Tax Law Article 13. It reports unrelated business taxable income, New York additions and subtractions, any business allocation, and the resulting tax, payments, and balance due or overpayment.
What you'll need
- A complete copy of your federal return. The form requires you to attach it.
- Federal and New York State computations if you claim a New York net operating loss deduction on line 12.
- A list of business locations if you claim the Schedule A allocation. Include each location, the nature of its activities, and the number and duties of employees.
- A gross rents list for Schedule A, line 27, if applicable.
- Supporting documentation for an amended return. Mark the applicable items in the amended return information area and attach documentation.
- Prepayment details, if applicable, including payment dates and amounts, any payment with Form CT-5, any installments made using Form CT-400, and overpayments credited from prior years.
How to file
The form says to see the instructions for where to file. The supplied text does not provide a mailing address or e-file directions.
To complete the return:
- Enter your tax period, organization information, EIN, NAICS business code from your federal return, and principal unrelated business activity.
- Complete the income and tax calculation and any applicable schedules. Attach a complete copy of your federal return.
- Have an authorized person complete and sign the certification.
- If payment is due, enter the line 22 amount on line A. Make the payment payable to New York State Corporation Tax, attach it in the designated area, and detach all check stubs.
Common mistakes
- Completing Schedule A without a regular place of business outside New York State. The form says to leave the schedule blank in that situation.
- Missing required attachments. Attach a complete federal return, and include the computations, lists, or amended return documentation required for your entries.
- Leaving the overpayment box unmarked. Mark an X in that box if you claim an overpayment.
- Leaving check stubs attached. The payment directions say to detach all check stubs.
- Overlooking the ceased-operations box. Mark it if you ceased operating the unrelated business during the tax year covered by the return.
Questions people ask
Are estimated tax payments required?
No. The form states that taxpayers subject to the unrelated business income tax are not required to make estimated tax payments. If you made these payments, report them on lines 44a, 44b, and 44c.
When do I complete Schedule A?
Leave Schedule A blank if you did not maintain a regular place of business outside New York State. The form defines a regular place of business as an office, factory, warehouse, or other space regularly used in your unrelated business. If you claim the allocation, attach the required business-location list.
How is the tax calculated?
Line 15 applies a 9% rate to allocated taxable income on line 14. On line 17, enter the larger of that amount or the minimum tax on line 16.
Can I apply an overpayment to next year?
Yes. Enter the amount you want credited to next year on line 24. Line 25 is the refund amount, calculated by subtracting line 24 from the overpayment on line 23.