It costs a lot to be poor in the state of Washington. Residents who make the least amount of money pay about 17% of their income in state and local taxes, according to a new report from the Institute on Taxation and Economic Policy. Meanwhile, Washington's highest earners cough up just 2.4% of their income for such taxes. The high tax rate on the poor, coupled with that huge gap in the tax burden between the poor and the top 1%. is why Washington ranks as the most regressive-tax state in the nation, according to the liberal think tank's study. other states where the poor are bearing some of the heaviest tax burdens in the country, include Florida, Texas, South Dakota and Illinois. There, the poor pay between 11% and 13% of their income in state and local taxes, compared to the 2% to 5% paid by the highest earners.