To mail in my 2019 Illinois State Income Tax Return, do I need to send copies of the W2, 1095C, SSA 1099, and a copy of our property tax bill?

[RobertG]

If you are mailing your Illinois State return; attach your W-2 and any 1099 forms that show State tax withheld to support the amount you claim as Illinois Income Tax withheld.

The other forms are not required.

When you print out your return using TurboTax you will also print out the filing instructions.

[ConnorE]

Hi @RobertG , 

How are you?

I had a quick question about filing my Illinois state tax return. When I mail in my return, do I only need to mail in my Illinois W-2 or do I need to mail in all W-2's, 1099's, etc from 2019 (even if they are not from Illinois)?

I am just unsure whether or not it is necessary to attach W-2's from other states or just IL. 

Thank you for your help!

[RobertG]

Attach your W-2 and 1099 forms to support the amount you claim as Illinois Income Tax withheld on Line 26. 

You only need the forms with Illinois withholding.