Bank of America's ( BAC) acquisition of Merrill Lynch secured its position as the biggest bank in the country, according to a report issued late Wednesday.

BofA now tops the list of U.S. banks and thrifts with $2.49 trillion worth of assets, $310.4 billion more than No. 2 competitor JPMorgan Chase ( JPM), according to a report by SNL Financial.

JPMorgan still leads Bank of America in terms of deposits, however, holding over $1 trillion in consumer dollars, vs. BofA's $979.1 billion. Without the Merrill acquisition, BofA would have ranked third behind JPMorgan and Citigroup ( C), which has $1.94 trillion in assets and $774.2 billion in deposits at the end of 2008.

Behind those three banking behemoths came Wells Fargo ( WFC), with $1.31 trillion in assets and $781.4 billion in deposits.

The list is an illustration of the "too-big-to-fail" notion that has led unprecedented government support of troubled financial institutions like Citi, Fannie Mae ( FNM), Freddie Mac ( FRE) and AIG ( AIG). Those top four banks hold 66% of U.S. banking assets and 58% of total deposits - and have also received over $144 billion in government funding to secure their financial health and support their acquisitions of troubled firms.

Rounding out the top 10 banks were HSBC ( HBC), PNC ( PNC), US Bancorp ( USB), Bank of New York Mellon ( BK), SunTrust ( STI) and Capital One ( COF) - each of which hold a fraction of the top four banks' deposits and assets.