Some analysts expect rates to gradually move higher this year as the economy improves and investors move out of bonds and into stocks. But the Federal Reserve has said it will continue to buy longer-term Treasuries as part of its quantitative easing program, a policy designed to push rates lower.

So far, banks have been able to offset low interest rates by managing expenses and cutting costs. Morgan Stanley, for example, announced plans last week to cut 1,600 jobs. Analysts say more layoffs could be in the works as banks focus on maximizing efficiency.

Another way banks are managing expenses is by settling lawsuits. Just last week, Federal regulators announced an $8.5 billion settlement involving 10 banks over alleged foreclosure abuses. And Bank of America reached a $10.3 billion settlement with Fannie Mae to deal with questionable home loans it sold to the government-backed mortgage financer during the housing bubble.

"Banks are putting more and more of their problems behind them," said Sinegal. "Every piece of litigation that is resolved is a positive."