Minnesota carries the highest corporate tax rate by state at a flat 9.8% — the highest rate of any state imposing a traditional flat corporate income tax. Specifically, combined with the federal rate of 21%, Minnesota corporations face a 28.7% combined rate — the highest combined corporate tax burden of any state. Consequently, corporations with significant Minnesota operations or sales face materially higher total tax burdens than equivalent operations in low-rate or zero-rate states. Furthermore, Hawaii’s graduated rate reaches 9.6% at its highest bracket — approaching Minnesota’s flat rate for profitable corporations. Additionally, Alaska’s graduated rate reaches 9.4% at its highest bracket — making these three states the most expensive combined-rate environments in the nation.