Buffett says he's still paying lower tax rate than his secretary. Warren Buffett says despite a higher tax bill this year than in 2012, he'll likely still pay a lower rate than his secretary. Warren Buffett says even though he and other top earners are paying higher taxes this year, he thinks he's still paying a lower rate than his secretary. In 2013, capital gains for those earning more than $400,000 ($450,000 for couples) will be taxed at 20%, up from 15%.