Is it necessary to file in CO if I am not a resident and I only made $2,100 there?

[SweetieJean · Accepted solution]

You must file a Colorado income tax return if during the year you were:

• A full-year resident of Colorado, or
• A part-year resident of Colorado with taxable income during that part of the year you were a resident, or
• A nonresident of Colorado with Colorado source income;

AND

• You are required to file a federal income tax return, or
• You have a Colorado income tax liability for the year.

https://www.colorado.gov/pacific/tax/individual-income-tax-quick-answers at Filing Requirements.