According to the Idaho Department of Revenue "nonresidents must file an Idaho income tax return if their gross income from Idaho sources is more than $2,500." You can confirm this statement of fact at the following Idaho government webpage:
https://tax.idaho.gov/i-1039.cfm#sub3
Thus, if you collected more than $2,500 in rent (gross income, not net income, which is income after deductions) on your Idaho rental property, then the answer to your question would be yes, you are legally required to file an Idaho state tax return. This is true even where you may end up actually owing no Idaho taxes, after all rental deductions, depreciation allowances, etc. are included.
Please also keep in mind as well that your taxable Idaho rental income (if any) is also included on your Oregon state tax return, since you are an Oregon resident. For that reason and also to avoid any problems with "double-taxation," of the same income by more than one state, you should be allowed a credit on your Oregon state return for any taxes that you may end up owing to Idaho. Thus, it's important that you complete your TurboTax tax return in the correct "sequencing" order, if you end up filing an Idaho state return.
This is true in the TurboTax software, so that the state tax credits "flow" properly in the program. That preparation sequence should be: Federal first, nonresident state second, and then resident state third. Or, for you, Federal, then Idaho, then Oregon. That will ensure the correct (mechanical) flow-through of state tax credits in TurboTax.
If you have further
questions, encounter any difficulties, or just want to speak with a live tax
expert who can walk you through your TurboTax entries (including the ability to
screen-share with your computer), please feel free to contact us. We
would be happy to help you (and as a paying customer, the call is free to
you). Here is a link where you can create a support ticket and reach us:
https://support.turbotax.intuit.com/contact/
Thank you for asking this question.
