Colorado Tax Withholding Requirements for Employers: Filing and Year-End W-2s

Colorado tax withholding requirements for employers start with a single rule: if you pay wages to anyone working in Colorado, you must withhold state income tax at 4.40% of adjusted taxable wages for 2026 and remit it to the Colorado Department of Revenue. That duty covers Colorado residents wherever they perform the work and nonresidents for any services physically performed inside the state. You act as a collecting agent for the DOR, and you are personally liable for the tax whether or not you actually deducted it from the paycheck.

Register and Open a Withholding Account

Before you withhold or remit anything, register with the Colorado Department of Revenue to open a wage withholding account. The standard path is Form CR 0100, the Colorado Sales Tax and Withholding Account Application, filed online or on paper.¹ Once registered, you receive a Colorado Account Number (CAN) that must appear on every filing and every piece of correspondence with the DOR.²

Keep records of total wages paid and Colorado tax withheld for each employee. The IRS requires employment tax records be retained for at least four years after the tax becomes due or is paid, whichever is later.³ Those records support your annual reconciliation and protect you in an audit.

Collect the Right Withholding Certificate From Each Employee

Every new hire must submit a current federal Form W-4, and Colorado uses that W-4 as the default basis for calculating state withholding. If an employee gives you nothing else, calculate from the W-4 alone. That default is built to cover the employee’s full-year Colorado tax liability and usually produces a small refund at filing.⁴

Colorado also offers an optional state-specific form, the DR 0004, which lets employees adjust state withholding independent of the federal W-4. An employee might use it to claim a different number of exemptions, request additional withholding, or reduce withholding when they expect large deductions. If an employee gives you a DR 0004, calculate Colorado withholding from that form instead of the W-4.⁵

Calculate What to Withhold

Use Form DR 1098, the Colorado Withholding Worksheet for Employers, for each pay period.⁶ It walks you through adjusting gross wages for filing status, the standard deduction, and any additional instructions from the W-4 or DR 0004. For 2026, the built-in standard deduction is $11,000 for married filing jointly or qualifying surviving spouse, and $5,500 for every other filing status.⁷

Apply Colorado’s flat 4.40% income tax rate to the adjusted amount. Payroll software performs the same calculation automatically; the worksheet is the manual version.

Supplemental Wages

Irregular payments like bonuses, commissions, and severance are supplemental wages. You can withhold on these at a flat rate equal to the income tax rate rather than running them through the full worksheet. For 2026, that flat supplemental rate is 4.40%.

Nonresident Employees

Employees who live outside Colorado but work inside the state are subject to Colorado withholding on the portion of wages tied to work performed here. An employee counts as physically present in Colorado on any day they spend the majority of working hours in the state, including travel time into Colorado to perform services.⁸

When a nonresident splits a pay period between Colorado and elsewhere, apportion wages by the ratio of Colorado workdays to total workdays. If someone works 4 of 20 days in Colorado during a pay period, 20% of that period’s wages is subject to Colorado withholding.⁸

Some nonresident workers are exempt. These include rail, air, and motor carrier employees who work across multiple states; active-duty servicemembers and their spouses stationed in Colorado under military orders; and employees who telecommute from outside Colorado even when their employer is based here.⁸

File and Pay on Your Assigned Schedule

How often you file and remit depends on your total annual Colorado withholding. The DOR assigns one of three schedules:⁹

Weekly, for employers with annual withholding above $50,000. Tax accumulated through any Friday is due by the third business day after that Friday.¹⁰
Monthly, for employers with annual withholding of at least $7,000 but not more than $50,000. Returns and payment are due by the 15th of the following month.
Quarterly, for employers with annual withholding under $7,000. Returns and payment are due by the last day of the month after the quarter ends: April 30, July 31, October 31, and January 31.

The periodic return is Form DR 1094, the Colorado W-2 Wage Withholding Tax Return, filed through the DOR’s Revenue Online portal.¹¹ Weekly filers must pay by Electronic Funds Transfer.¹² Other filers can pay by e-check, credit card, or debit card through Revenue Online.¹³ File a return for every period even if you paid no wages and withheld nothing.

Reconcile and File W-2s After Year-End

After the calendar year closes, reconcile the total tax withheld from employees against the total you remitted through your periodic DR 1094 filings. You do that on Form DR 1093, the Annual Transmittal of State W-2 Forms, which ties the individual W-2s to your periodic payments.¹⁴

Each employee must receive their W-2 by January 31 following the close of the tax year.¹⁵ The same January 31 deadline applies to filing the DR 1093 and submitting all W-2 copies to the DOR.¹⁶ Employers filing large numbers of W-2s must submit electronically through Revenue Online. Mismatches between your DR 1093 and your periodic payments usually generate a notice and may lead to a payroll audit.

Penalties and Personal Liability

Late filing or late payment triggers a penalty equal to the greater of $5 or 5% of the unpaid tax, plus an additional 0.5% for each full or partial month the balance stays unpaid, capped at 12% of the tax owed.¹⁷ The penalty starts accruing on the original due date, so even a few days late means the 5% floor.

Interest runs on top. For 2026, the DOR charges 8% annual interest if you pay before receiving a notice of deficiency, or within 30 days after one is issued. Miss that window and the rate rises to 11%.¹⁷ Additional penalties apply for willful failure to file, fraudulent returns, or negligent disregard of the withholding rules.

Federal failure-to-deposit penalties run alongside the state ones. The IRS charges 2% for deposits 1 to 5 days late, 5% for 6 to 15 days, and 10% beyond 15 days, climbing to 15% if payment doesn’t arrive within 10 days of a formal IRS notice.¹⁸ A missed deposit can cost you at both levels.

Withholding is a trust fund tax. The money belongs to the employee and the government the moment it’s taken out of a paycheck. Officers, owners, and anyone with authority over payroll can be held personally liable for trust fund taxes that aren’t remitted, even if the business itself becomes insolvent.

FAMLI Premiums: A Separate Obligation

Income tax withholding isn’t your only payroll duty to the state. Every Colorado business with at least one employee must also register with the Family and Medical Leave Insurance (FAMLI) Division through the My FAMLI+ Employer portal.¹⁹ This registration is separate from your DOR account and is a frequent oversight for new employers.

For 2026, premium rates depend on workforce size. Employers with 10 or more employees pay 0.88% of wages per quarter, split evenly between employer and employee at 0.44% each; the employer may choose to cover the whole premium. Employers with 9 or fewer employees owe 0.44% of wages per quarter and are not required to contribute an employer share, though they may deduct up to 0.44% from employee wages. Premiums apply to wages up to the federal Social Security wage base, which is $184,500 for 2026.²⁰²¹

Quarterly premium payments and wage reports follow the unemployment insurance schedule: April 30, July 31, October 31, and January 31. Update your employee headcount in My FAMLI+ by February 28 each year; miss that deadline and the FAMLI Division assumes you have 10 or more employees and bills the full 0.88% rate for the year.¹⁹

Closing a Withholding Account

When you stop paying wages, whether through a sale, shutdown, or change of legal structure, formally close your withholding account with the DOR. File Form DR 1108, the Business Tax Account Closure Form, listing the accounts to close and the effective date.²² Skip this step and the account stays open; the DOR may assess tax for periods with no activity.

Before you close, pay all final wages, make any remaining withholding deposits, and file your last DR 1094 for the period. You still owe the annual DR 1093 reconciliation and W-2 distribution for any year wages were paid. On the federal side, notify the IRS and file final employment tax returns.²³ Keep payroll records for at least four years after your final tax payment, since both the DOR and IRS can audit closed accounts within that window.³

1
Department of Revenue – Taxation. CR 0100 – Colorado Sales Tax and Withholding Account Application
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Colorado Department of Revenue. Instructions for the Colorado Sales Tax and Withholding Account Application
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Internal Revenue Service. Topic No. 305, Recordkeeping
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Colorado Department of Revenue. Colorado Employee Withholding Certificate
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Colorado Department of Revenue. 2026 Colorado Employee Withholding Certificate
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Department of Revenue – Taxation. DR 1098 – Colorado Withholding Worksheet for Employers
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Colorado Department of Revenue. 2026 Colorado Withholding Worksheet for Employers
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Colorado Department of Revenue. Colorado Wage Withholding Tax Guide
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Department of Revenue – Taxation. Colorado Tax Withholding Requirements for Employers – Section: What Is My Filing Frequency?
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Department of Revenue – Taxation. Colorado Taxes and Fees Due Date Guide
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Department of Revenue – Taxation. Colorado W-2 Wage Withholding Tax Return
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Department of Revenue – Taxation. Colorado Wage Withholding Tax Guide
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Department of Revenue – Taxation. File Withholding Online
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Colorado Department of Revenue. DR 1093 – Annual Transmittal of State W-2 Forms
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Social Security Administration. Deadline Dates to File W-2s
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Colorado Department of Revenue. DR 1093 – Annual Transmittal of State W-2 Forms
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Department of Revenue – Taxation. Tax Topics: Penalties and Interest
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Internal Revenue Service. Failure to Deposit Penalty
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Family and Medical Leave Insurance. Employers
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Family and Medical Leave Insurance. Update Your Employee Headcount for 2026 Premiums
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Social Security Administration. Contribution and Benefit Base
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Department of Revenue – Taxation. DR 1108 – Business Tax Account Closure Form
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Internal Revenue Service. What Business Owners Need to Do When Closing Their Doors for Good