Analysts expect the San Francisco-based bank to make $20.8 billion for 2013. That’s more than Bank of America (BAC), Goldman Sachs (GS), and Morgan Stanley (MS) are expected to earn combined this year. And it’s $3.5 billion more than Wells’ closest profit rival, JPMorgan Chase (JPM), which had held the largest profit title for three years in a row.

But JPMorgan’s legal woes have cleared the road for the Wells Fargo wagon to take the lead in the profit race. JPMorgan is in the process of negotiating a $13 billion settlement with regulators related to the bank’s mortgage business.

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For a long time, the traditional business of taking deposits and making loans was seen as the less desirable part of the financial industry. The banks wanted to be on Wall Street, where Goldman and others were making big profits on investment banking and trading. But an increase in regulations and diminished demand for Wall Street’s riskier investments have flipped that equation. That’s benefited Wells Fargo, which largely stuck with its traditional banking business as others were reaching for profits on Wall Street.

What’s more, Wells has used the financial crisis to solidify its lead in mortgage lending as rivals BofA and Citigroup (C) have had to tend to their wounds from the financial crisis, and others disappeared completely. Wells is now by far the nation’s largest mortgage lender, issuing roughly a third of all home loans. That paid off last year and in the first half of this year, as low interest rates sparked a refinance boom.

Bank investors and analysts say return on equity, or ROE, is a better measure of a bank’s profitability, because it adjusts for size and how much capital is being deployed to produce earnings. But even on that measure, Wells is racing ahead of its rivals. So far this year, Wells ROE has averaged nearly 14%. Compare that to 11% and 10% at Goldman and JPMorgan, respectively. Before the financial crisis, Goldman routinely had an ROE that topped 20%.

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On an ROE basis, Wells trails U.S. Bank (USB), which has also shunned Wall Street businesses. That bank had an ROE of 16% in its most recent quarter.

It’s been quite a while since any U.S. bank ranked as the most profitable in the world. That distinction goes to China’s largest banks, though bad loans appear to be piling up there.

And even in the U.S., analysts don’t expect Wells to stay the most profitable (in net income terms) for long. The title is expected to return to JPMorgan next year. So Wells, enjoy it while it lasts.