Source: Carl Davis, Kelly Davis, Matthew Gardner, Harley Heimovitz, Robert S. McIntyre, Richard Phillips, Alla Sapozhnikova, Meg Wiehe, Institute on Taxation & Economic Policy, 4th edition, January 2013
From the press release:
State tax systems take a much larger share from middle- and low-income families than from wealthy families, according to the fourth edition of “Who Pays? A Distributional Analysis of the Tax Systems in All 50 States,” released today by the Institute on Taxation and Economic Policy (ITEP). Combining all of the state and local income, property, sales and excise taxes state residents pay, the average overall effective tax rates by income group nationwide are 11.1 percent for the bottom 20 percent, 9.4 percent for the middle 20 percent and 5.6 percent for the top one percent.
The ten states whose tax systems are tilted most heavily towards high earners (from most to least regressive) are Washington, Florida, South Dakota, Illinois, Texas, Tennessee, Arizona, Pennsylvania, Indiana, Alabama. In these states, middle-income families pay up to three times as high a share of their income as the wealthiest families; low-income families pay up to six times as much.