Oklahoma Business State Tax Extension I S Corporations Filing Guide

Form 504-C | Application for Extension of Time to File an Oklahoma Income Tax Return for Corporations, Partnerships, and Fiduciaries  ·  S-Corporations  ·  Business Filing Guide

• Oklahoma S Corporations are subject to state business tax filing requirements, administered by the Oklahoma Tax Commission. Oklahoma 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
• Oklahoma 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 Oklahoma extended deadline becomes 15-Oct-26. No separate state extension form is required—the federal extension serves as your Oklahoma extension.

Use the Oklahoma | Online Tax Extension Payment to pay electronically. For mail-in payments, use Form 504-C | Application for Extension of Time to File an Oklahoma Income Tax Return for Corporations, Partnerships, and Fiduciaries and send to: Oklahoma Tax Commission P.O. Box 26890 Oklahoma City, OK 73126-0890

• File IRS Form 7004 with the IRS to secure your federal extension, which Oklahoma automatically honors.
• Use the state online payment portal for fast, convenient electronic payment.
• Set a reminder to file your completed Oklahoma S-Corporations return by 15-Oct-26.

• Oklahoma’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 15-Oct-26.
• Quick Reference Table
• State Abbreviation
• OK
• State Name
• Oklahoma
• Business Entity Type
• S-Corporations
• Extension Status
• Approved with Federal
• Extended Due Date
• 15-Oct-26
• Other Information
• Oklahoma grants an automatic extension if a valid federal extension is obtained and at least 90% of the tax due is paid by the original return due date. A copy of the federal extension must be enclosed with the final 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. 6-month automatic extension if federal extension is filed by the original due date of return and no tax is due. Additional 1-month extension may be granted if Form 504 is filed by the extended due date.
• Online Payment
• Oklahoma | Online Tax Extension Payment
• Payment Voucher Form
• Form 504-C | Application for Extension of Time to File an Oklahoma Income Tax Return for Corporations, Partnerships, and Fiduciaries
• State Payment Agency
• Oklahoma Tax Commission
• Mailing Address with Payment
• Oklahoma Tax Commission P.O. Box 26890 Oklahoma City, OK 73126-0890

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
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4. 4Your TaxPro files your Oklahoma return by 15-Oct-26

Quick Reference Table