How to answer the "Colorado portion of Federal Adjustments" and "Colorado Subtractions from Federal AGI"?

[CL6]

Using Turbo Tax Premier 2020.  I'm a resident of California so this is for my non-resident CO state tax return.  For the first question, Federal allows $300 of charitable donations as adjustment. Do I also claim the $300 as a portion of my Colorado income? Or is there an opportunity to claim it on my CA state income tax form? If so, which is better or can I do both?

For the second question there's about $10,000 of federal subtractions. How do I determine what's the CO portion?

[hbl3973 · Accepted solution]

CL6,

CO part-year and nonresident income tax is computed by first totaling all income from all sources and then determining what portion is CO income. The ratio of the two is applied to things like the $300 charitable deduction and the portion of computed tax actually due CO.  (For some items, the ratio only includes earned income.)  The CO webpage

https://tax.colorado.gov/income-tax-topics-part-year-residents-nonresidents

Gives you the details on how to apportion the various federal deductions.  I can