Oregon Business Tax Extension 2026: 2025 Tax-Year Filing Guide
LLC & Partnership · S Corporation · C Corporation · Fiduciary
This guide explains how to file a Oregon (OR) business tax extension for each entity type. For example, CBT taxpayers generally receive six months, while partnerships generally receive five months. However, estimated tax remains due by the original deadline.
Need a pro? Connect with a U.S.-based CPA or EA to prepare and file your OR return.
Remember, payment is still due by the original deadline. In other words, extensions only extend filing time.
Oregon (OR) rules depend on entity type. Next, confirm the entity’s classification, file the required extension or retain federal proof when applicable, and pay required tax by the original deadline.
Oregon LLC Tax Extension: Filing Details
A calendar-year partnership or LLC taxed as a partnership generally files Forms OR-65, as applicable, when a Oregon filing obligation applies. For the 2025 calendar-year return, the extended filing deadline is September 15, 2026.
In addition, the extension applies to filing time only. Therefore, pay required Oregon tax by the original deadline to limit penalties and interest.
The extension applies to filing time only. Pay required Oregon tax by the original deadline to limit penalties and interest.
Oregon S Corporation Tax Extension: Filing Details
For an S corporation, a calendar-year business generally files Form OR-20-S when it has a Oregon filing obligation. For a 2025 calendar-year return, the extended deadline depends on entity type and Oregon’s federal-extension rules.
Oregon C Corporation Tax Extension: Filing Details
For a C corporation, a calendar-year business generally files Form OR-20 or OR-20-INC and must follow Oregon corporate-income-tax extension rules. For a 2025 calendar-year return, the extended deadline depends on entity type and Oregon’s federal-extension rules.
The extension applies to filing time only. Pay required Oregon tax by the original deadline to limit penalties and interest.
The extension applies to filing time only. Pay required Oregon tax by the original deadline to limit penalties and interest.
Fiduciary, Estate, and Trust Filing Details
Finally, a calendar-year estate or trust generally files Form OR-41 when it has a Oregon fiduciary filing obligation. For a 2025 calendar-year return, the extended deadline depends on entity type and Oregon’s federal-extension rules.
Quick Reference: Deadlines and Forms
The table below provides a quick reference to Oregon business tax extensions. See our IRS Form 7004 guide, Oregon individual tax extension, and business tax extension resource for related guidance.
| Entity Type | OR Return Form | Extension Method | Extended Deadline |
|---|---|---|---|
| LLC / Partnership | OR-65 / OR-65 | Federal 5-month; Form OR-EXT-CAT / Form OR-EXT-CAT | Sept. 15, 2026 |
| S Corporation | OR-20-S | Form 7004 | Oct. 15, 2026 |
| C Corporation | OR-20 / OR-20-INC | Form 7004 | Oct. 15, 2026 |
| Fiduciary / Estate / Trust | OR-41 | Form Form 7004 | Oct. 15, 2026 |
Frequently Asked Questions
Quick answers about Oregon business tax extensions – but always confirm the current rules with the Oregon Division of Taxation.
Visit OR DORYes. However, the applicable entity-specific requirements listed above must be satisfied. Oregon grants extensions to LLCs, partnerships, S corporations, C corporations, and fiduciaries, but the rules – including which form to file, how long the extension lasts, and the payment threshold – vary by entity type.
Generally no. In other words, pay required tax by the original deadline and confirm the current state payment rules. An extension of time to file does not extend the time to pay – failing to pay by the original deadline can result in penalties and interest, even if the return is filed within the extended window.
No. In practice, partnerships, S corporations, C corporations, and fiduciaries can use different original dates, extension periods, or forms. For 2025 calendar-year returns filed in 2026, partnerships and LLCs taxed as partnerships get a five-month extension (Sept. 15), while the others generally get a six-month extension (Oct. 15).
Review the Oregon Division of Taxation guidance for the entity’s return. Additionally, the DOR publishes the most current forms (Form 7004, Form OR-EXT-CAT, Form 7004, etc.) and any changes to extension periods or payment thresholds.
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