If you earn income in Colorado that isn’t subject to state withholding, you generally owe Colorado quarterly tax payments four times a year: April 15, June 15, September 15, and January 15 of the following year. You submit each payment with Form DR 0104EP or electronically through the state’s Revenue Online portal. The rule applies to you if your net Colorado tax liability after credits will be $1,000 or more for the year and nobody is withholding Colorado tax on your behalf.1Colorado Public Law. Colorado Code CRS 39-22-605 – Failure by Individual to Pay Estimated Income Tax
Who Owes Estimated Payments
The threshold is simple. If your Colorado income tax for the year, after allowable credits but before counting any withholding or estimated payments, will reach $1,000, you need to pay as you go.1Colorado Public Law. Colorado Code CRS 39-22-605 – Failure by Individual to Pay Estimated Income Tax This usually catches freelancers, independent contractors, small business owners, landlords, and people with substantial investment income.
Married couples filing jointly apply the $1,000 threshold to their combined liability, and if you file joint federal estimated tax, you must also file joint Colorado estimated tax.2Colorado Department of Revenue. Estimated Income Tax
Have a W-2 job plus side income? You only owe quarterly payments if the gap between what your employer withholds and what you’ll owe still clears $1,000. Many people in that spot simply ask HR to bump up state withholding instead of dealing with vouchers.
The Four Due Dates
Colorado splits the year into four installment periods:3Department of Revenue – Taxation. Individual Income Tax – Estimated Payments
- First quarter: April 15
- Second quarter: June 15
- Third quarter: September 15
- Fourth quarter: January 15 of the following year
If a due date lands on a weekend or state holiday, the deadline shifts to the next business day. Each installment is expected to be one-quarter of your required annual payment, but Colorado assesses underpayment based on the cumulative amount at each date, so paying more one quarter and less the next isn’t automatically a problem.
Mailing a check? The U.S. Postal Service postmark date counts as the date of payment. A payment postmarked on or before the due date is timely even if it arrives later. A postmark after the deadline makes it late.4Colorado Department of Revenue. Regulation 39-21-119 – Date Document or Payment Considered Made
How Much to Pay Each Quarter
Colorado applies a flat 4.40% income tax rate to your state taxable income.5Department of Revenue – Taxation. Individual Income Tax – Frequently Asked Questions Your Colorado taxable income starts with your federal taxable income and adjusts for state-specific additions and subtractions.6Colorado General Assembly. Individual Income Tax
Here’s the back-of-the-envelope version. Expecting $80,000 of Colorado taxable income? Your annual state tax would be $80,000 × 0.044 = $3,520. Divide by four, and each quarterly payment lands at $880. The DR 0104EP includes a worksheet that walks through the full calculation with credits and withholding factored in.
Safe Harbor: The Minimum You Actually Have to Pay
You don’t have to predict your current-year tax exactly. Colorado gives you three safe harbors, and hitting any one of them shields you from an underpayment penalty even if you end up owing more at filing time:
- Pay at least 70% of what you actually owe for the current year.7Legal Information Institute. 39-22-605 – Estimated Individual Income Tax
- Pay 100% of your prior year’s net Colorado tax liability. This option requires that your prior year was a full 12-month year, you filed a Colorado return, and your federal adjusted gross income was $150,000 or less ($75,000 or less if married filing separately).7Legal Information Institute. 39-22-605 – Estimated Individual Income Tax
- Pay 110% of your prior year’s net Colorado tax liability if your prior-year federal AGI was over $150,000.1Colorado Public Law. Colorado Code CRS 39-22-605 – Failure by Individual to Pay Estimated Income Tax
Your required annual payment is whichever option produces the smallest number. For most self-employed taxpayers with reasonably steady income, the prior-year safe harbor is the easiest to work with because it doesn’t require guessing.
How to Submit Your Payment
The quickest route is the state’s Revenue Online portal at Colorado.gov/RevenueOnline. You can pay by electronic funds transfer, e-check, or credit or debit card. EFT and e-check carry no fees. Credit and debit cards add a convenience fee calculated as (payment amount + $0.75) × 2.25%.8Colorado Department of Revenue. Payment Frequently Asked Questions On a $3,000 payment that fee comes to roughly $67.50. Online payments produce an immediate confirmation number and typically post to your account within a few business days.
Prefer paper? Mail your check or money order with the completed DR 0104EP voucher to:3Department of Revenue – Taxation. Individual Income Tax – Estimated Payments
Colorado Department of Revenue
Denver, CO 80261-0008
Make the check payable to “Colorado Department of Revenue.” Write your Social Security number, the tax year, and “Form DR 0104EP” on the check itself. Don’t send a check without the voucher attached. A trackable mailing method gives you proof of timely submission if anything goes wrong in transit.
Use the DR 0104EP version for the correct tax year, since the Department publishes an updated form annually.9Department of Revenue – Taxation. DR 0104EP – Individual Estimated Income Tax Payment Form The voucher asks for your Social Security Number or ITIN, name, address, and payment amount. If you’re filing jointly, list the same name and SSN that will appear first on your annual return.10Colorado Department of Revenue. Individual Estimated Income Tax Payment Form
If You Underpay or Miss a Deadline
If your payments fall short of every safe harbor, Colorado charges interest on the shortfall for each quarter. The 2026 interest rate for estimated tax underpayments is 8% annually.11Department of Revenue – Taxation. Tax Topics – Penalties and Interest Interest compounds daily and doesn’t cap.
The amount is calculated separately for each quarter based on how much you underpaid and the number of days between the installment due date and when you actually paid or filed. Colorado uses Form DR 0204 to compute the penalty, and you file it with your annual return if one is owed.12Colorado Department of Revenue. Computation of Penalty Due Based on Underpayment of Colorado Individual Estimated Tax Because this is interest on the shortfall and not a flat penalty, partial payments still help: underpaying by $500 for one quarter costs far less than skipping four installments on a $10,000 liability.
Alternatives if the Standard Schedule Doesn’t Fit
Two situations change the standard four-payment schedule.
If at least two-thirds of your gross income comes from farming or fishing, you can make a single estimated payment by January 15 of the following tax year instead of four quarterly ones. You can skip estimated payments entirely by filing your Colorado return and paying the full tax due by March 1.7Legal Information Institute. 39-22-605 – Estimated Individual Income Tax
If your income is lumpy, with most of it arriving late in the year, you can use the annualized income installment method. Each quarterly payment is sized to the income you’ve actually earned through the end of the month before the due date, rather than one-quarter of a projected annual total. You can only use this method on your Colorado return if you also elected it federally.7Legal Information Institute. 39-22-605 – Estimated Individual Income Tax Keep records of your allocation and be ready to produce them if the Department asks.
One boundary worth flagging: everything above covers individual taxpayers. C corporations use Form DR 0112EP, face a $5,000 threshold instead of $1,000, and have a December 15 fourth-quarter deadline rather than January 15.13Department of Revenue – Taxation. Business Income Tax – Estimated Payments Sole proprietors, partners, and S corporation shareholders report business income on their individual returns, so they stay on the individual form and schedule described here.