Michigan
For 2009 Illinois has a Personal state income tax flat rate range of 3 % of federal adjusted gross income The above information comes from the RETIREMENTLIVING com website
state corporate income taxes
Some tax income at a flat percentage rate, a proportional tax. Some charge a percentage of a person's federal income tax. Others have a progressive tax like the federal income tax. A few states only tax interests and dividends from investments, not wages and salary. Seven states choose to impose no income tax. These states are Alaska, Florida, Nevada, South Dakota, Texas, Washington, and Wyoming.
Generally yes, but only for state income tax returns and only in states where either same-sex marriage or civil unions (or both) have been legalized. On exception to this is Illinois. However, Illinois' state income tax is a flat tax and there is no mathematical difference between filing as a married couple or as two individuals.
The choices
223.14
Personal Income Taxes Tax Rate Range: Flat rate of 3.07%
A proportional income tax on individual income with no regard to how large your income is
Illinois Personal Income Taxes Tax Rate Range: Flat rate of 3% of federal adjusted gross income
flat income tax
Illinois has a flat tax for individual income.