Wisconsin Business State Tax Extension I S Corporations Filing Guide

Form Corp-ES | Wisconsin Corporation Estimated Tax  ·  S-Corporations  ·  Business Filing Guide

• Wisconsin S Corporations are subject to state business tax filing requirements, administered by the Wisconsin Department of Revenue. Wisconsin grants an automatic extension tied to an approved IRS extension, making the process simple for businesses that have already filed IRS Form 7004.
• Extension Period & Extended Deadline
• Wisconsin automatically grants an extension to file, provided you have obtained an approved federal extension from the IRS by filing IRS Form 7004. With a valid IRS extension, the Wisconsin extended deadline becomes October 15, 2026. No separate state extension form is required—the federal extension serves as your Wisconsin extension.

Use the Wisconsin | Online Tax Extension Payment to pay electronically. For mail-in payments, use Form Corp-ES | Wisconsin Corporation Estimated Tax and send to: Wisconsin Department of Revenue P.O. Box 930208 Milwaukee, WI 53293-0208

• File IRS Form 7004 with the IRS to secure your federal extension, which Wisconsin automatically honors.
• Use the state online payment portal for fast, convenient electronic payment.
• Set a reminder to file your completed Wisconsin S-Corporations return by October 15, 2026.

• Wisconsin’s business tax extension is straightforward once your federal extension is approved. Pay any balance due on time and file your S-Corporations return by October 15, 2026.
• Quick Reference Table
• State Abbreviation
• WI
• State Name
• Wisconsin
• Business Entity Type
• S-Corporations
• Extension Status
• Approved with Federal
• Extended Due Date
• October 15, 2026
• Other Information
• Wisconsin grants your business an automatic 6-month extension provided you have obtained an approved IRS extension. A copy of the federal extension must be attached to the final Wisconsin return when filed. The extension is NOT an extension to pay any taxes you may have due. Tax payments are due by the original return due date.
• Online Payment
• Wisconsin | Online Tax Extension Payment
• Payment Voucher Form
• Form Corp-ES | Wisconsin Corporation Estimated Tax
• State Payment Agency
• Wisconsin Department of Revenue
• Mailing Address with Payment
• Wisconsin Department of Revenue P.O. Box 930208 Milwaukee, WI 53293-0208

Business tax returns are complex—a licensed CPA or Enrolled Agent can maximize deductions, ensure accurate calculations, and handle filing on your behalf. Here's how working with a TaxPro typically goes:

1. 1Get matched with a verified U.S.-based CPA or Enrolled Agent
2. 2Upload your business documents via secure drag-and-drop
3. 3Review and approve your return with upfront, transparent fees
4. 4Your TaxPro files your Wisconsin return by October 15, 2026

Quick Reference Table