DR 0112: C Corporation Income Tax Return (form only) (2025)
Colorado · Colorado DOR · Used for tax years 2025
Form DR 0112 is the Colorado C Corporation Income Tax Return. It reports federal taxable income and Colorado adjustments to determine Colorado taxable income and income tax.
Who files this form
Each C corporation doing business in Colorado must file DR 0112.
- IRS tax-exempt organizations generally do not owe Colorado income tax. However, they must file DR 0112 if they file federal Form 990-T to report unrelated business taxable income from Colorado sources or business activity in Colorado.
- Insurance companies subject to Colorado's tax on gross premiums under section 10-3-209, C.R.S., are exempt from Colorado income tax.
- S corporations use DR 0106 instead.
The form also says that nonprofit associations and the listed types of local governments claiming the Alternative Transportation Options Credit must claim it on DR 0112.
When it's due
For the 2025 tax year, the form gives these deadlines:
- File and pay: The fifteenth day of the fifth month following the close of the taxable year. The form lists May 15 for calendar-year filers.
- Filing extension: An automatic six-month extension, listed as November 15 for calendar-year filers. This does not extend the time to pay. Use DR 0158-C to make an extension payment before filing.
- Weekend or legal holiday: If the due date or extension date falls on a weekend or legal holiday, filing or payment is due the next business day.
What you'll need
Start with your completed federal income tax return. DR 0112 uses federal taxable income from Form 1120, line 30, or Form 990-T, Part I, line 11.
Have your corporation's Colorado Account Number, FEIN, mailing address, federal tax year and accounting method, and six-digit NAICS code ready. You also need contact information for the person who maintains the corporation's books.
Supporting documents depend on what you report. They may include:
- Income apportionment: DR 0112RF for interstate corporations apportioning and allocating income.
- Other additions, subtractions or credit recapture: Written explanations supporting the amounts reported.
- Tax payments and withholding: Payment records, DR 1079 for applicable Colorado real estate withholding, and Forms W-2G for lottery or gaming withholding.
- Credits: Applicable credit forms and required certificates, such as DR 0112CR, DR 1366, DR 1370 or DR 1330.
- Vehicle credits: DR 0617, the purchase invoice or lease agreement, and proof of permanent Colorado registration for each vehicle claimed.
- Business personal property credit: A copy of the assessor statement.
- SALT Parity Act credit: Copies of the Colorado K-1 forms showing the credit.
- Marijuana or natural medicine business deduction: Actual and pro forma federal schedules, plus your Colorado MED or NMD license number.
- Estimated tax penalty: DR 0205 if you calculate and report this penalty.
How to file
- Complete your federal income tax return first. Use the same tax year and accounting method for Colorado.
- Complete DR 0112, including the appropriate apportionment method and separate, consolidated, combined or combined/consolidated filing designation.
- Include all required supporting forms, schedules and explanations. An authorized corporate officer must sign the return under penalty of perjury. The form also provides signing rules for receivers, trustees in bankruptcy and assignees operating the corporation's business or property.
File electronically: Use the free, secure Revenue Online system at Colorado.gov/RevenueOnline on a computer, smartphone or tablet. You may also use e-file software or a paid tax preparer. Revenue Online offers an E-Filer Attachment option for supporting documents.
File by mail: If you cannot file electronically, mail your return as instructed. The printed address for a return mailed with a check or money order is:
Colorado Department of Revenue
Denver, CO 80261-0006
Payment options are available through Revenue Online. If you claim the Aircraft Modification for Unleaded Fuel Credit for more than one aircraft, you must file electronically.
Common mistakes
- Sending an incomplete paper return. The form warns that missing supporting schedules, forms or documentation will delay processing.
- Treating the filing extension as extra time to pay. The automatic extension applies only to filing, not payment.
- Entering unverified estimated payments. Carefully review payment records and verify estimated payments through Revenue Online before completing line 28.
- Claiming a vehicle credit you assigned away. You cannot claim the credit if you assigned it to a financing entity or motor vehicle dealer.
- Claiming the business personal property credit for real estate. Real property is not eligible.
- Attaching the DR 1323 employer plan report to this return. The form specifically says not to file that report with DR 0112.
- Using incorrect direct deposit details. Check the routing number, account number and account type with your financial institution. Include account-number hyphens, but not spaces or special symbols.
- Using the wrong year's amendment form. Use the form version for the tax year you are amending.
Questions people ask
What tax rate does the 2025 form use?
Line 19 instructs you to multiply Colorado taxable income on line 18 by 4.4% (0.044).
Do I need to make estimated tax payments for next year?
The form says you must make estimated payments using DR 0112EP if next year's Colorado tax liability will be greater than $5,000 after subtracting credits.
How can I receive my refund?
You can authorize direct deposit by entering your routing number, account number and account type. Otherwise, a refund check will be mailed to the address on the return. You may also apply some or all of your overpayment to 2026 estimated tax on line 54. The Department will intercept your refund if you owe taxes or other debts to Colorado or the IRS.
How do I correct a return I already filed?
You can amend through Revenue Online even if you originally filed on paper. If you cannot amend online, mail DR 0112X using the version for the year being amended. A Colorado amendment is required for federal changes affecting the calculation of Colorado income tax and is due within 180 days after the federal adjustment is finalized.