U.S. Millionaires Moved to Action. Almost half of U.S. millionaires do not feel wealthy and are taking action to reassess their portfolios and rebuild their wealth, despite having an average of $3.5 million in investable assets and $306,000 in annual household income. That's according to Fidelity's newly released third annual Millionaire Outlook^SM study, which examines the investing attitudes and behaviors of more than 1,000 millionaire households.