Substitute Form Developer
Welcome to the Colorado Department of Revenue’s
Substitute Form Developer home page. Here you will find the resources dedicated to ensuring your forms meet Colorado tax processing and imaging standards.
Substitute Form Developers are required to receive approval from CDOR before the release or distribution of any substitute forms. To get started:
Make sure you have obtained a 4 digit vendor identification code per a product from the National Association of Computerized Tax Processors (NACTP). Obtaining a vendor ID is free by filling out the Vendor ID Request Form. Click here to access the National Association of Computerized Tax Processors site. Click here to access the Vendor ID Request Form.
Click here to fill out the current year's Letter of Intent (LOI).
Read the Substitute Form Developer Specifications and 2D Specifications. Click here to access the Form Developer Specifications and 2D Specifications page.
Review submission guidelines. Click here to access the submission guidelines page.
Once your LOI has been approved, you may send substitute forms.
Send any questions to dor_fd_vendor@state.co.us or check out our F.A.Q. section. Click here to open email link dor_fd_vendor@state.co.us.
Dates & Timelines
08/25/23 - The LOI has been update. Please see Announcements for details.
08/23/23 - An update Word version of the LOI has been posted.
08/18/23 - Letter of Intent has been posted.
Letter of Intent Deadline - There is no longer a deadline for the LOI. An LOI approval will be required before submitting form.
08/28/23 - The first set of forms will be posted for replication.
The first submission of forms marked as "Final", is due within six weeks of original posting.
Some forms will have line reference updates later in the season. A submission or courtesy copy is due within two weeks of the updated posting.