Moynihan also commented on lawsuits facing the financial industry, as a government lawsuit accusing BofA's Countrywide unit of fraud in the sale of billions of dollars of toxic mortgage loans to Fannie Mae and Freddie Mac is scheduled to go to trial later this month.
"To go through a trial is tremendously expensive, for both us and the other side, and typically that's what leads you to some rational conclusion," said Moynihan—adding, if that happens, it's usually at the last minute.
The alleged practices that the government is suing over happened in 2007 and 2008, before BofA bought Countrywide.
"We always make an assessment ... what's the cost to defend yourself versus the cost of a settlement, and then what are the ramifications of that settlement," Moynihan explained. "Unfortunately we've had to make it more than we'd like over the last couple years, honestly."
It was just over two years ago that Buffett's Berkshire took a $5 billion stake in Bank of America.
Moynihan said Bank of America was in no rush to redeem Buffett's preferred shares, since BofA has more expensive debt it wants to retire first. Similarly, Buffett said it was highly unlikely he would exercise his warrants in the bank before 2021.
(Read more: Squawking with big brains on Wall St.)
—By CNBC's Becky Quick and Matthew J. Belvedere.