Article I of the United States Constitution created and empowered our legislative branch of government. The United States Congress leads the legislative branch. Congress includes both the House of Representatives and the Senate. Generally speaking, Congress makes our laws.
Income Tax returns and schedules. The Illinois Business Income Tax rate for tax years. ending on or after December 31, 2015, is 5.25 percent. (.0525) for taxpayers taxed as corporations, and 3.75. percent (.0375) for taxpayers taxed as trusts or estates. The instructions for overpayments to be carried forward.
â¢ For individuals, trusts, and estates, the Illinois Income Tax rate is. decreasing from 5 percent (.05) to 3.75 percent (.0375). â¢ For corporations (excluding S corporations), the Illinois Income Tax. rate is decreasing from 7 percent (.07) to 5.25 percent (.0525).