How can I tell why I am going to have to submit Form DR 1778 for Colorado return? I have never had to do this before and would like to know what forms they need and why.

[KeshaH]

The Colorado Form 1778 is required when you need to attach additional documentation that can't be electronically filed with your Colorado tax return. Common reasons you'd need to submit Form 1778 are:

- submitting copies of other state tax returns

- sending documentation to claim certain credits

- claiming a refund on behalf of a deceased person

TurboTax should provide more details about which documentation you need to attach when you complete your filing. You'll need to print Form 1778, attach the supporting documents, and mail them to the Colorado Department of Revenue after e-filing your return.