The Consumer Financial Protection Bureau has accused TCF National Bank (TCB), a Minnesota-based bank with 360 branches in seven states, of tricking hundreds of thousands of customers into accepting costly overdraft services.

Back in 2007, the Federal Reserve gave consumers overdraft protections, requiring banks to ask customers to opt-in to overdraft services that came with expensive charges.

“The Opt-In Rule posed a serious threat to TCF, which depends on overdraft revenue to a greater degree than its competitors,” the CFPB wrote in its complaint suing the bank. According to CFPB Director Richard Cordray, this is because the bank doesn’t rake in substantial revenue from other common consumer banking products like credit cards and mortgages.

“A substantial part of [TCF’s] revenue comes from fees,” Cordray said on a conference call Thursday. The opt-in rule would be a problem. “In 2009, TCF estimated that $182 million in annual revenues was at risk.”

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