Why do I owe IL State taxes

I am married and I live and work in IL but my husband works in MO.

My IL state wages were $58634.76 and state income tax was $2902.45.

My husband's MO wages were $43823.68 and state income tax was $1311.00.

 

We owe about $89 in MO state taxes, which makes sense to me. We always owe a little there. However, for IL Turbotax is saying we owe another $535 in IL state taxes. 

 

Could you please explain where that would be coming from? We have no other income and at the 4.95% for our IL income, the $2902.45 seems correct.

 

Thanks!