Officials say the campaign received the money after Edwards dropped out of the presidential race, and he was not entitled to the money.
Edwards ended his run for the White House in January 2008, nearly three-and-a-half years ago, but he has continued spending an average of $60,000 a month. The funds include federal matching money, public money and money from contributors.
The FEC ruling was unanimous against Edwards, who was indicted in June on eight federal felony charges for alleged violations of campaign finance laws related to his cover-up of an affair with former campaign videographer Rielle Hunter.
Edwards's lawyers had challenged the findings, saying they incurred "unanticipated expenses" related to the Justice Department's investigation.