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When you're looking for a bank stock to add to your portfolio, one of the first things you should consider is profitability. Aside from valuation, in fact, nothing is more important.

To gauge profitability, you look at a bank's return on equity. This measures how much a bank earns relative to the amount of shareholder equity used to generate the earnings.

Here's how it's calculated:

A higher return on equity is better than a lower one. And at a bare minimum, you want to see a bank earn at least 10% on its equity. If you factor in the opportunity cost of not investing your money elsewhere, a bank that earns less than this is effectively destroying shareholder value.

With all of this in mind, here are the top 10 bank stocks ranked by profitability:


Return on Equity (TTM)

Price-to-Book Value Ratio

U.S. Bancorp



Wells Fargo



Commerce Bancshares



Northern Trust



Fifth Third Bancorp



State Street



JPMorgan Chase



Huntington Bancshares



Cullen/Frost Bankers



Bank of New York Mellon



*The entire list included the 23 bank stocks on the KBW Bank Index -- First Niagara Financial Group was excluded in light of its recent merger with KeyCorp. Data source:

The top four are worth paying particular attention to -- that is, U.S. Bancorp (NYSE:USB), Wells Fargo (NYSE:WFC), Commerce Bancshares (NASDAQ:CBSH), and Northern Trust (NASDAQ:NTRS).

Not only are these banks the most profitable, but their shares are also the most expensive. For instance, U.S. Bancorp tops the list with its 14.4% return on equity and comes in near the top with a valuation of 1.79 times book value.

The same is true for Commerce Bancshares and Northern Trust, both of which reported double-digit returns on equity over the past year and trade for at or near twice their respective book values. Even Wells Fargo, which has a lower valuation than the other three, is still priced above most of its peers when you expand the list to include a larger sample of banks.

It may go without saying, but the relationship between these two metrics isn't a coincidence. Banks that earn more money are given higher valuations. And as an offset for banks with lower profitability, their shares trade at lower valuations.

In this instance, then, if you were on the hunt for a top bank stock to hold for the long run, you'd be excused for concluding that Wells Fargo is a bargain -- at least compared to other highly profitable banks. While it's just as profitable as U.S. Bancorp, Commerce Bancshares, and Northern Trust, its valuation is considerably lower.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.