I live in Missouri but work on a military base in Illinois both as a Reservist and a full time civilian employee. Do I have to do a Missouri and Illinois tax return? Why?

[jackiemanetzke]

Confused on how this works and why I would need to file more then one when my W-2 shows Missouri and that I paid state taxes. Am I paying taxes in both states? Should I be getting taxes back from one or the other? Do I not need to file an Illinois tax return at all?

[TomD8]

Your earnings for serving in the Armed Forces Reserves are NOT taxed by Illinois.

But your earnings from working as a civilian in Illinois ARE taxable by Illinois.

Therefore you must file a non-resident Illinois return, in addition to your home state Missouri return.

You'll be able to take a credit on your MO return for the taxes paid to IL, so you won't be double-taxed.

In TT, be sure to complete the non-resident IL return before you do your MO return, so that the credit can be calculated and applied correctly.

https://www2.illinois.gov/rev/questionsandanswers/Pages/100.aspx