Form4T: Form4T (2025)
Wisconsin · Wisconsin DOR · Used for tax years 2025
Wisconsin Form 4T is the Exempt Organization Business Franchise or Income Tax Return for organizations taxable as corporations or trusts. It reports unrelated business taxable income, Wisconsin adjustments, taxes, credits, payments, and any amount due or refund.
Who files this form
Wisconsin Form 4T is the Exempt Organization Business Franchise or Income Tax Return. It has separate sections for exempt organizations taxable as corporations and those taxable as trusts that report unrelated business taxable income.
The form does not state filing thresholds or complete rules for determining who must file.
When it's due
For the 2025 tax year, the printed due date is the 15th day of the 5th month following the close of the taxable year, or the 15th day of the 4th month for certain trusts and IRAs.
If you have an extension of time to file, enter the extended due date in item F.
What you'll need
- Federal return: You must include a copy of federal Form 990-T or 4720, including attachments.
- Organization details: Have the organization's address, Wisconsin DFI number, federal employer ID number, business activity code, and state and year of organization available. Trusts must provide the trustee's name.
- Income and tax information: Gather the amounts needed for unrelated business income, Wisconsin additions and subtractions, gross receipts, estimated tax payments, and Wisconsin tax withheld.
- Schedules that apply: The form references Schedule CR for credits, Form N for nonapportionable income, an apportionment schedule, Schedule RT for certain related entity expenses, and Form U or Schedule U for interest, penalties, and late fees.
- Special attachments: Include Schedule AR for an amended return. Complete and include Schedule DE if you are the sole owner of any LLCs. For the subtraction for income from related entities whose expenses were disallowed, obtain Schedule RT-1 from the related entity and submit it with the return.
If you check an applicable box in item E, attach an explanation as directed.
How to file
Complete the form using black ink. Use lines 1 through 13 for organizations taxable as corporations, or lines 14 through 23 for organizations taxable as trusts. Complete the applicable remaining sections and have the officer or trustee sign and date the return.
The form refers to electronic filing but does not provide electronic filing steps.
If you are not filing electronically, make your check payable to Wisconsin Department of Revenue and mail your return to:
Wisconsin Department of Revenue
PO Box 8908
Madison WI 53708-8908
Paper clip your check or money order in the space indicated. Do not staple or bind the return. Include the required federal return and attachments.
Common mistakes
- Using the wrong tax section: Trusts must not fill in lines 1 through 13. Corporations must not fill in lines 14 through 23.
- Formatting amounts incorrectly: Do not enter commas or cents. Show negative numbers with a minus sign, such as
-1000, not parentheses. - Stapling or binding the return: The form says not to staple or bind it. Paper clip the payment where indicated.
- Leaving out the federal return: Include federal Form 990-T or 4720 and its attachments.
- Missing the annualized-income checkbox: If you annualized income on Form U or Schedule U, check the space indicated on line 36.
Questions people ask
Can an overpayment go toward next year's estimated tax?
Yes. Line 39 lets you apply part or all of the overpayment on line 38 to 2026 estimated tax. Line 40 shows the remaining refund.
Can someone else discuss this return with the department?
Yes. Select “Yes” in the Third Party Designee section and provide the designee's name, phone number, and personal identification number (PIN).
How do donations affect my refund or amount owed?
The endangered resources donation and veterans trust fund donation each decrease your refund or increase the amount you owe.
What if the organization owns an LLC?
If the organization is the sole owner of any LLCs, complete Schedule DE and include it with the return. The form also asks whether you included those entities' incomes in the return.