Important: If you owe Illinois and/or IRS income taxes and do not file an IRS and
Illinois tax return or extension by the Tax Due Date, you will be subject to IRS and IL late filing penalties. Estimate IRS late filing, payment penalties
. In addition, if you do not pay your taxes by the Tax deadline, you will be subject to late tax payment penalties. Filing an extension on time will ONLY
eliminate the late filing penalties but not the late tax payment penalties. Late filing penalties are generally higher than late payment penalties, thus file something on time even if you can't pay anything on time!