DR 0105: Fiduciary Income Tax Return (form only) (2025)
Colorado · Colorado DOR · Used for tax years 2025
Form DR 0105 is the Colorado Fiduciary Income Tax Return for estates and trusts. It reports federal taxable income and Colorado additions and deductions used to determine Colorado income tax.
Who files this form
Generally, a Colorado fiduciary income tax return is required for:
- A resident estate or trust; or
- A nonresident estate or trust with Colorado-source income.
The estate or trust must also either be required to file a federal income tax return, including an information return such as Form 5227 or 1041A, or have a Colorado tax liability.
A resident estate is an estate administered in Colorado other than through an ancillary proceeding. A resident trust is any trust administered in Colorado.
When it's due
For the 2025 tax-year return, the printed deadline rules are:
- File and pay: By the fifteenth day of the fourth month after the taxable year closes, stated as April 15 for calendar-year filers.
- Filing extension: An automatic six-month extension, stated as October 15 for calendar-year filers. This does not extend the time to pay. Use DR 0158-F to make an extension payment before filing.
- Weekends and legal holidays: If the due date or extension date falls on either, the deadline moves to the next business day.
An amended Colorado return reporting a federal adjustment is due within 180 days after the adjustment is finalized.
What you'll need
Complete the federal income tax return first. You will use its information to prepare DR 0105.
Have these details ready:
- Estate or trust name, creation date, and federal employer identification number (FEIN).
- Fiduciary name, mailing address, and Colorado Account Number, if assigned.
- Fiscal-year beginning and ending dates, if applicable.
- Beneficiary names, addresses, Social Security numbers, and income allocation information for the applicable schedules.
- Payment and withholding information, including any W-2s, 1099s, and W-2Gs.
Submit the supporting documents required for your situation. These include:
- Copies of any DR 0106K received if the estate or trust is a partnership partner or S corporation shareholder.
- Schedule E for a nonresident estate or trust, Schedule F when reporting alternative minimum tax, and Schedule G when claiming its credits.
- All W-2Gs when reporting lottery or gaming withholding.
- Required credit forms and certificates. For a purchased or leased vehicle credit, include DR 0617, the purchase invoice or lease agreement, and proof of permanent Colorado registration.
- DR 1316 when claiming the Colorado agricultural land capital gain subtraction.
- Actual and pro forma federal business schedules and the Colorado license number when claiming the marijuana or natural medicine business deduction.
- Copies of other states’ tax returns when claiming credit for tax paid to those states.
Other deductions and credits may require additional documents listed in the supplied text.
How to file
Read the filing guide and complete the federal return first. Use the same tax year for Colorado as for federal tax purposes. Complete the applicable schedules and sign the return under penalty of perjury.
File electronically: File and pay through the free, secure system at Colorado.gov/RevenueOnline using a computer, smartphone, or tablet. The text also allows private e-file software or a paid tax preparer.
File by mail: If you cannot file electronically, use the address that matches your payment method.
With a check or money order:
Colorado Department of Revenue
Denver, CO 80261-0006
Without a check or money order:
Colorado Department of Revenue
Denver, CO 80261-0005
No street address is required because these ZIP codes are used only by the Department of Revenue.
Electronic filing is required if you claim the aircraft modification for unleaded fuel credit for more than one aircraft.
Common mistakes
- Leaving out supporting documents: Incomplete documentation delays processing.
- Treating the filing extension as a payment extension: The automatic extension applies only to filing, not payment.
- Combining a bankruptcy estate return with the debtor’s return: Submit DR 0105 with estate documentation only. Do not attach the debtor’s DR 0104 or use DR 0105 as its transmittal form.
- Claiming a vehicle credit you assigned: You cannot claim the purchased or leased vehicle credit if you assigned it to a financing entity or motor vehicle dealer.
- Including the DR 1323 employer plan report with this return: The text says not to file that report with DR 0105.
- Ignoring electronic-filing reminders: The Department strongly recommends electronic filing for enterprise zone, CHIPS Zone, and Strategic Capital Tax credits, and for credits for tax paid to more than one state. Paper filing may delay processing.
Questions people ask
Are estimated tax payments required?
No. Estimated payments are not required for a fiduciary return. To make voluntary payments, use the options at Colorado.gov/RevenueOnline or mail a check or money order with DR 0105EP.
Is there a Colorado K-1 for an estate or trust to issue to beneficiaries?
The text says the Department currently does not have a Colorado K-1 for an estate or trust to report items allocated to beneficiaries. If the estate or trust receives a DR 0106K from a partnership or S corporation, submit a copy with DR 0105.
How do I amend a fiduciary return?
You can report a correction at Colorado.gov/RevenueOnline, even if you originally filed on paper. To amend on paper, complete a new DR 0105 and mark the Amended Return box. You must amend for a change to a federally determined item or amount used to calculate Colorado income tax.
How do I request a final determination of a deceased person’s tax liability?
Submit DR 0253 separately from the return.