When it comes to bank stocks, size does indeed matter.

Not only do the largest regional banks -- including SunTrust Banks (NYSE:STI), BB&T (NYSE:BBT), and Capital One (NYSE:COF) -- benefit from economies of scale, but they're also typically much more diversified than their community banking counterparts. These are two of the reasons that shares of Capital One and BB&T, after adjusting for dividends and buybacks, have outperformed the S&P 500 over the past two decades.

Given this, investors in bank stocks should keep a rough tally of where specific banks fall in the size spectrum. The slideshow below does just that, using data from the third-quarter earnings releases of SunTrust Banks, BB&T, Capital One, and others, to rank the biggest regional banks in the United States by total assets.

John Maxfield has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.