Only nine U.S. states continue to require retirees to pay state income taxes on their Social Security benefits:

Provisional income between $25,000 - $34,000 for single filers, $32,000 - $44,000 for joint filers, up to 50% of Social Security benefits will be taxable. Provisional income above $34,000 for single filers or above $44,000 for joint filers, up to 85% of Social Security benefits will be taxable.