Colorado Business Tax Extension 2026: 2025 Tax-Year Filing Guide
LLC & Partnership · S Corporation · C Corporation · Fiduciary
This guide explains how to file a Colorado (CO) business tax extension for each entity type. If you also need the federal filing step, see our IRS Form 7004 guide. For example, Colorado provides automatic filing extensions by entity type, but an extension of time to file does not extend the time to pay. 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 CO return.
Remember, payment is still due by the original deadline. In other words, extensions only extend filing time.
Colorado (CO) 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.
Colorado LLC Tax Extension: Filing Details
A calendar-year partnership or LLC taxed as a partnership generally files Form DR 0106, as applicable, when a Colorado filing obligation applies. For the 2025 calendar-year return, the extended filing deadline is October 15, 2026.
In addition, the extension applies to filing time only. Therefore, pay required Colorado tax by the original deadline to limit penalties and interest.
The extension applies to filing time only. Pay required Colorado tax by the original deadline to limit penalties and interest.
Colorado S Corporation Tax Extension: Filing Details
For an S corporation, a calendar-year business generally files Form DR 0106, as applicable, when a Colorado filing obligation applies. For the 2025 calendar-year return, the extended filing deadline is October 15, 2026.
Colorado C Corporation Tax Extension: Filing Details
For a C corporation, a calendar-year business generally files Form DR 0112, as applicable, when a Colorado filing obligation applies. For the 2025 calendar-year return, the extended filing deadline is November 16, 2026.
The extension applies to filing time only. Pay required Colorado tax by the original deadline to limit penalties and interest.
The extension applies to filing time only. Pay required Colorado 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 DR 0105, as applicable, when a Colorado filing obligation applies. For the 2025 calendar-year return, the extended filing deadline is October 15, 2026.
Quick Reference: Deadlines and Forms
The table below provides a quick reference to Colorado business tax extensions. For broader filing context, visit our business tax extension resource.
| Entity Type | CO Return Form | Extension Method | Extended Deadline |
|---|---|---|---|
| LLC / Partnership | DR 0106 | Automatic filing extension; DR 0158-N if payment is required | Oct. 15, 2026 |
| S Corporation | DR 0106 | DR 0158-C | Oct. 15, 2026 |
| C Corporation | DR 0112 | DR 0158-C | Nov. 16, 2026 |
| Fiduciary / Estate / Trust | DR 0105 | Automatic filing extension; confirm any required payment with the Colorado Department of Revenue | Oct. 15, 2026 |
Frequently Asked Questions
Quick answers about Colorado business tax extensions – but always confirm the current rules with the Colorado Department of Revenue.
Visit Colorado Department of RevenueYes. However, the applicable entity-specific requirements listed above must be satisfied. Colorado 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 payment requirements – vary by entity type. For individual returns, see our Colorado individual tax extension.
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 and S corporations generally have a six-month extension to October 15; C corporations have a six-month extension to November 15, observed as November 16, 2026.
Review the Colorado Department of Revenue guidance for the entity’s return. Additionally, the DOR publishes the most current forms (DR 0158-C, DR 0158-N, DR 0105, etc.) and any changes to extension periods or payment thresholds.
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