Tax season is officially open in Colorado. The Colorado Department of Revenue, Taxation Division, recently announced that taxpayers can now file their 2023 state income tax returns. They've shared practical tips to help Coloradans avoid delays, reduce filing mistakes, and receive refunds faster.
Whether you're a full-time resident, part-year filer, or someone who earned income in Colorado last year, this guide will walk you through everything you need to know. From who must file and what forms to use, to deductions, credits, and the filing methods available—we’ll break down the process clearly, one step at a time.
Colorado has a flat income tax rate and closely ties state filing requirements to your federal return, so starting early and getting organized is key. We’ll also show you how to file your taxes online for free, claim helpful tax credits, and avoid common errors that might hold up your return.
If you filed a federal income tax return for 2023, chances are you’ll also need to file one with the state of Colorado. Unlike some states that set minimum income thresholds, Colorado’s requirement is tied directly to your federal filing obligation or whether you earned taxable income from within the state.
You must file a Colorado tax return if you meet any of the following conditions:
Colorado also requires you to file even if you don’t owe anything, as long as you had a federal filing requirement. This is especially important for people with lower incomes, retirees, or those who are eligible for a refund based on tax credits.
Even if you don’t think you owe state taxes, you may still qualify for a rebate or refund. For example, full-year residents over 18 can receive a sales tax refund—but only if they file. Filing also helps the state determine eligibility for certain income tax credits and ensures accurate records for future years.
Colorado follows the same basic tax calendar as the IRS, and meeting these deadlines is essential—even if you’re not ready to pay immediately. Missing important dates can lead to penalties, delayed refunds, and unnecessary stress.
Your 2023 Colorado tax return and any payment you owe are due by April 15, 2024. This deadline applies whether you file electronically or by mail. The state accepts e-filed returns until midnight, while paper returns must be postmarked no later than that day.
Colorado grants a six-month automatic extension to file—but it’s essential to know that this extension does not apply to payments. If you owe taxes, you must still estimate and pay at least 90% of your tax liability by April 15 to avoid interest and penalties.
To make an extension payment, use Form DR 0158-I or pay directly through Revenue Online.
If you fail to file on time, Colorado may charge:
Even if you can’t pay immediately, it’s better to file your tax return on time and arrange a payment plan later.
If you’re due a refund, there's no penalty for filing late—but there’s also no reason to wait. Filing early may help you avoid identity verification issues or delays in processing.
Filing your Colorado tax return starts with the proper forms. Colorado offers several versions depending on your income type, residency status, and whether you're claiming credits or deductions. Choosing the correct form ensures your return is processed correctly and helps avoid unnecessary delays.
Depending on your situation, you may also need to attach one or more of the following:
All forms and instructions are available for download from the Colorado Department of Revenue’s website at tax.colorado.gov. You can also file electronically through Revenue Online or compatible tax software.
Filing your Colorado income tax return doesn’t have to be overwhelming. This step-by-step guide is designed to walk you through the process, whether you’re handling your taxes, using software, or working with a tax preparer.
Start by filing your federal tax return (Form 1040). Colorado uses your adjusted gross income (AGI) from the federal return as the starting point for your state filing. Without a completed federal return, you won’t be able to move forward.
Have the following documents ready before starting:
This is the main form. You’ll enter:
You may need:
Before submitting:
You can file your taxes online through:
Or, file by mail if you prefer paper returns.
Filing your Colorado tax return isn’t just about reporting income—it’s also a chance to reduce your debt or boost your refund by claiming credits and deductions. Colorado offers a range of income tax credits, subtractions, and rebates to help eligible individuals and families maximize their tax savings.
Several income tax credit programs can reduce the amount you owe—or increase your refund—if you meet specific income requirements or situations.
You’ll typically need to file Form DR 0104CR to claim these credits.
Colorado allows several deductions (referred to as "subtractions" on state forms) that can lower your income tax burden:
Use Form DR 0104AD to report these subtractions.
Full-year Colorado residents age 18 and older may be eligible for the state sales tax rebate—a benefit that requires filing a return even if no tax is owed. The rebate is $800 for individuals and $1,600 for joint filers, provided you meet the residency and income criteria.
Property tax and rent-related rebates are also available through the Property Tax/Rent/Heat Credit (PTC) Rebate program. This is especially useful for seniors, people with disabilities, and low-income households.
Consulting with a tax expert or using Colorado’s Revenue Online system can help if you're unsure whether you qualify for a particular credit or deduction. They can guide you through the documentation needed and ensure you claim everything you’re entitled to.
Once you’ve gathered your documents and completed your return, it’s time to choose how you’ll submit it. Colorado supports both online filing and traditional mail-in methods, and each comes with its pros and cons depending on your access to technology, location, and personal preferences.
The Colorado Department of Revenue recommends e-filing to speed up processing and reduce errors. You can file for free using:
Filing your taxes online offers several benefits:
For those who need assistance, the state offers guidance through its website, and many nonprofit programs in Denver and other areas provide free tax help for qualifying individuals.
You can still file your tax return on paper if you prefer. Download the forms from the Colorado Department website, complete them by hand, and mail them to the correct address based on your payment situation.
Mailing Tips:
You can visit Revenue Online or call the Department of Revenue directly if you encounter issues. Filing doesn’t have to be a hassle—many filers can complete the process in under an hour, especially using digital tools and step-by-step guides.
Whether you owe money or expect a refund, Colorado offers multiple options to keep the process smooth. Understanding how payments and refunds work can help avoid delays, penalties, or unnecessary paperwork.
If your return shows that you owe money, you have a few options for paying:
Paying online through Revenue Online is the fastest and most secure option. You can:
Online payments are tracked immediately, helping you avoid late penalties and interest.
If you prefer to mail a check or money order:
To avoid penalties, make sure your payment is postmarked by April 15. Even if you’ve already filed, a payment is considered late if it isn’t submitted by the deadline.
You'll receive a refund if you’ve paid more than you owe. You can choose:
To track your refund, go to tax.colorado.gov/refund and enter:
Colorado processes payments and refunds equally, regardless of how you file. Whether you use a CPA, file by mail, or submit through your phone, your return will be handled in the same queue.
Before you submit your Colorado return, take a few minutes to review this checklist. It’ll help ensure your filing is complete, accurate, and ready to go—online or by mail.
The earned income tax credit is available to individuals and families with low to moderate incomes. To qualify, a person must have earned income from employment or self-employment and meet income limits based on household size. A tax expert can help determine eligibility, especially for part-year residents or those with multiple income sources.
Many part-year residents can still claim the child tax credit if they meet IRS guidelines and earned qualifying income. Even if you lived in Colorado for only half the year, you may be eligible if your dependents meet age and relationship requirements. A tax expert can confirm your eligibility based on federal and state rules.
To get the maximum refund, claim all eligible credits and deductions, including child care costs, property tax rebates, and education expenses. Submitting receipts for groceries, school supplies, and charitable donations may help if they meet deduction guidelines. Filing early and consulting with tax experts also improves accuracy and helps reduce refund delays.
Even a straightforward return can hide missed savings. A tax expert may identify credit deductions that a person could overlook. This is especially true if you recently moved, are self-employed, or own a home. Free help is often available from nonprofit programs or VITA sites, especially for seniors or lower-income people.
Yes, you can file your Colorado tax returns from several years back. While you might not qualify for a refund after a specific period, you can still reduce tax liabilities or update records. If you previously paid for medical, school, or groceries that may qualify under past deductions, consult a tax expert to see what’s still available.