My husband is a resident of Illinois but as of October of last year, he has been working in Iowa, so does this make him a part year resident of Illinois or is he still a full year resident and a non-resident of Iowa?
I know this may sound stupid but he IS and always has been a resident of Illinois and I personally don't think that just because he works outside of his home state, I don't think it should make him a part time resident.
Please help if you can.
Thank you!

He is a full-time resident of Illinois and a non-resident of Iowa who receives income from an Iowa source.

It is my understanding that Iowa and Illinois has a reciprocity agreement where Illinois residents who work in Iowa need only pay Illinois taxes.

However, if the employer is unaware of this agreement, he may have withheld Iowa taxes, in which case you need to file an Iowa AND an Illinois tax return.

Don't worry about paying double taxes on the same salary. Illinois should give you a credit for the Iowa taxes paid.