Colorado Tax Deadlines: Individual & Corporate Filing Guide

Colorado Tax Deadlines: Individual & Corporate Filing Guide

Check Colorado tax deadlines for individuals and C Corporations. Confirm due dates, extension rules, and exemptions for S Corps and Partnerships.

Colorado Tax Deadlines at a Glance (2026)

Entity Type

Return Due

Extension

Individuals

April 15, 2026

October 15, 2026

C Corporations

April 15, 2026

October 15, 2026

S Corporations

March 16, 2026

September 15, 2026

Partnerships

March 16, 2026

September 15, 2026

PTE Election

Available and increasingly used for SALT mitigation.

Get hands-on with AI-powered tax automation today.

Start Free. No Credit Card Required.

Start 15-day Free Trial

Get hands-on with AI-powered tax automation today.

Start Free. No Credit Card Required.

Start 15-day Free Trial

Get hands-on with AI-powered tax automation today.

Start Free. No Credit Card Required.

Start 15-day Free Trial

Secure Conversations. Smarter Tax Strategies.

Built on industry-leading standards to keep your clients’ data safe and your firm audit-ready.

Find more

End-to-end Encryption

SOC 2 Type II

Monitoring Systems

24/7 intrusion detection

Quarterly scans & annual pen tests

Access Control

Multi‑Factor Authentication & Role‑based permissions

Regulation Compliant

TLS 256‑bit in transit & at rest

Secure Conversations. Smarter Tax Strategies.

Built on industry-leading standards to keep your clients’ data safe and your firm audit-ready.

Find more

End-to-end Encryption

SOC 2 Type II

Monitoring Systems

24/7 intrusion detection

Quarterly scans & annual pen tests

Access Control

Multi‑Factor Authentication & Role‑based permissions

Regulation Compliant

TLS 256‑bit in transit & at rest

Secure Conversations. Smarter Tax Strategies.

Built on industry-leading standards to keep your clients’ data safe and your firm audit-ready.

Find more

End-to-end Encryption

SOC 2 Type II

Monitoring Systems

24/7 intrusion detection
Quarterly scans & annual pen tests

Access Control

Multi‑Factor Authentication & Role‑based permissions

Regulation Compliant

TLS 256‑bit in transit & at rest
Customer Stories

Trusted by firms across the board

"Research used to be a black hole. Now, I just type the question and get a citable IRS answer in seconds."

Tax Manager

Sama Tributa

"80% faster first drafts. What used to take us two days is now done in two hours."

Managing Partner

Northbridge Tax Advisory

Customer Stories

Trusted by firms across the board

"Research used to be a black hole. Now, I just type the question and get a citable IRS answer in seconds."

Tax Manager

Sama Tributa

"80% faster first drafts. What used to take us two days is now done in two hours."

Managing Partner

Northbridge Tax Advisory

Customer Stories

Trusted by firms across the board

"Research used to be a black hole. Now, I just type the question and get a citable IRS answer in seconds."

Tax Manager

Sama Tributa

"80% faster first drafts. What used to take us two days is now done in two hours."

Managing Partner

Northbridge Tax Advisory