The Department strongly recommends that you submit
these documents using the e-Filer Attachment option at, which eliminates the
requirement to mail this form. Failure to timely submit required
documentation will result in denial of the related credit. Revenue
Online E-Filer Attachment provides you with a conrmation
number and will be available to the Department immediately.
Otherwise, complete this form, package it with your
documentation and mail to the Department. Using this form
can extend return processing time up to 6 weeks.
Mail to:
Colorado Department of Revenue
Denver, CO 80261-0006
You must resubmit your supporting documentation if you le
an amended return. DO NOT return this form in lieu of a
payment form or if you are ling a paper return. This form
is ONLY required if your taxes were e-led and your software
or preparer was unable to attach the required documentation
E-Filer Attachment Form
Instructions for DR 1778
DR 1778 (08/17/20)
Denver CO 80261-0006
For Tax Year (MM/DD/YY) or scal year beginning (MM/DD/YY)
Tax Type
Individual Income C Corporation Income Partnership Income S Corporation Income LLC Income
LP Income LLP Income LLLP Income Association Income Non-Prot Income
Please print or type
Taxpayer Last Name First Name Middle Initial
Spouse’s Last Name (if applicable) First Name Middle Initial
Taxpayer SSN or ITIN Spouse SSN or ITIN (if applicable) FEIN
Taxpayer Address
City State Zip
Mark the box for the documents submitted. See the Colorado Department of Revenue, Taxation Division website at for more information about these credits.
Other state(s) income tax return(s) Colorado Source Capital Gain Subtraction: DR 1316
Enterprise Zone Credit: DR 1366 and any applicable
certication forms from the Zone Administrator
Job Growth Incentive Tax Credit: Certication letter from
the Colorado Economic Development Commission
Gross Conservation Easement: DR 1305, DR 1305G,
and supplemental documentation
Affordable Housing Credit: CHFA certication
Aircraft Manufacturer New Employee Credit:
DR 0085 and/or DR 0086
Nonresident Partner, Shareholder or Members
Agreement: DR 0107
Innovative Motor Vehicle Credit: Vehicle registration
and the purchase invoice.
Plastic Recycling Credit: Required documentation
to substantiate credit (receipts, bills, etc)
Child Care Contribution Credit: DR 1317 School-to-Career Investment Credit: Certication letter.
Claim for refund on behalf of deceased taxpayer:
DR 0102, death certicate, and, if applicable, court
Other documentation for credits/subtractions claimed
(mark the Other box below and enter details)
Signature of Taxpayer or Preparer Date (MM/DD/YY)
E-Filer Attachment Form
DR 1778 (08/17/20)
Denver CO 80261-0006
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