Form St-556 - Sign into your online account and click the take me to. Preprinted paper forms can also. The illinois department of revenue dec. The illinois department of revenue dec. Click here to go to mytax illinois to file your return online.
The illinois department of revenue dec. The illinois department of revenue dec. Preprinted paper forms can also. Sign into your online account and click the take me to. Click here to go to mytax illinois to file your return online.