Here are the biggest banks in the country by assets, which is how the banking industry is measured.

BB&T 's deal to buy SunTrust Banks is slated to create the sixth-largest bank in the U.S. when it closes, squeezing in between U.S. Bancorp and PNC .

The so-called merger of equals was valued at $66 billion, the biggest bank deal since the financial crisis. The combined company will operate under a new name and have around $442 billion in assets, $301 billion in loans and $324 billion in deposits.

Wall Street players have been calling for the consolidation of regional banks, including Brian Moynihan, CEO of Bank of America, who spoke about this trend at the World Economic Forum last month in Davos, Switzerland.

"The emergence will come out of the consolidation of another round of people, which still has to happen in the United States. There are 6,000 banks ... and you will find them continue to consolidate. That's the core banking world, versus the capital markets world, which has consolidated a bit," Moynihan told CNBC.

— With reporting from CNBC's Michael Bloom.