Despite brand new tax rate reductions of the Jobs and Growth Tax Relief Reconciliation Act of 2003, leading marginal tax bracket for many retirees is really a whopping 46.3%. Why? Because Social Security benefits are subject to income income tax. Those affected are Social Security recipients who purchase the good fortune (misfortune?) always be subject to both the 25% taxes bracket as well as the 85% inclusion rate for Social Security benefits. Contributing a deductible $1,000 will lower the ...