topic Live in Illinois, worked in California in State tax filing

Live in Illinois, worked in California

The Doctor — Mon, 23 Feb 2026 13:34:51 GMT

My son works seasonally for the National Park Service. Last year he worked for the summer in California, and paid CA state tax. He is a full time resident in Illinois. The 2 years prior, he worked in Michigan which has a reciprocal agreement with Illinois, making filing a little easier.

I'm looking for the best way to handle this. Do I need to purchase the CA state software and file as a non resident?

TIA

Re: Live in Illinois, worked in California

Mike9241 — Thu, 02 Feb 2023 20:28:35 GMT

he needs to file a non-resident CA return and a resident IL return. on iL he takes credit for the CA taxes. IL schedule CR

Re: Live in Illinois, worked in California

DavidD66 — Thu, 02 Feb 2023 20:41:38 GMT

Yes, your son will have to file a California Non-Resident tax return, in addition to his Illinois state tax return. As an Illinois resident, 100% of his income is taxable by Illinois. However, they will give your son a credit for state tax paid to California. The credit is not a dollar for dollar credit; rather, it is calculated as the amount of Illinois tax that would be paid on the California income. It may not be as much as the California tax, but it won't be more.