The bank: After years of hyperactive acquisitions, Citigroup is now one of the largest banks in the world. It has a hand in everything from credit cards, consumer lending and retail banking to investment banking and corporate lending, and operates in more than 100 countries.

Stress level: High. Bank told to raise $5.5 billion in new capital by November.

Analysis: Don't be fooled by a good first-quarter profit. Citigroup hit that number largely through accounting adjustments. Exposure to toxic assets and weakness in major business lines are still severely stressing this bank and CEO Vikram Pandit, pictured above.

Key challenges: Citigroup is being hit by a double whammy. First, it has more than $35 billion in illiquid and toxic assets. Next, growing losses in areas such as credit cards, consumer loans and commercial real estate will make it tough for the bank to earn its way out of the problem. "We don't see Citi getting into the black until sometime in 2010," Fox-Pitt Kelton analyst David Trone says.

The bank: The biggest U.S. bank with $1 billion in deposits, JPMorgan Chase is a true "universal bank," with a large presence in everything from investment banking and credit cards to commercial banking and asset management.

Stress level: low. No need to raise new capital.

Analysis: CEO Jamie Dimon, pictured above, deserves kudos for steering clear of the mortgage mess. Before trouble hit, he dumped toxic assets on other players. Now, the bank looks well-capitalized.

Key challenges: With big exposure to credit cards and consumer lending, JPMorgan will have more stress if the economy worsens. On the bright side, its financial strength allowed it to pick up Bear Stearns and Washington Mutual on the cheap. Those moves should pay off nicely once the economy rebounds.

The bank: With more than 6,100 branches in 32 states and $884 million in deposits, Bank of America is the closest thing the U.S. has to a nationwide bank.

Stress level: high. B of A needs to raise $33.9 billion in new capital.

Analysis: Despite that huge deposit base, Bank of America's core capital remains thin. That makes it a candidate for more government funding (of the sort that's drawn protests, like the one pictured above.). "We do not think Bank of America's capital base is strong enough," Morningstar analyst Jaime Peters says.

Key challenges: Chief Ken Lewis took Bank of America on a shopping spree after he became CEO in 2001, gobbling up big players such as FleetBoston Financial and credit card company MBNA. Unfortunately, Lewis didn't know when to quit. Purchases of Merrill Lynch and Countrywide Financial last year took the bank knee-deep into the mortgage mess. Problems stemming from those buys plus weakness in credit cards and other lines of business will boost credit losses this year and next, Credit Suisse analyst Moshe Orenbuch says.

The bank: With $785 million in deposits and more than 6,600 branches, Wells Fargo is one of the largest U.S. banks. Wells Fargo recently doubled its size and morphed into a nationwide bank by purchasing Wachovia.

Stress level: medium. Wells Fargo needs to raise $13.7 billion in capital.

Analysis: The Wachovia deal put a strain on Wells Fargo's capital, which is now thin enough to raise a yellow flag.

Key challenges: With the Wachovia purchase, about 25% of Wells Fargo's home mortgage book is in California, one of the lousiest states for real estate. Rising unemployment and a worsening economy also have put pressure on the bank's consumer- and commercial-loan books. Look for higher credit losses this year and in 2010.

The bank: Chiefly an investment bank and asset manager, Goldman Sachs Group wouldn't even be on the list of companies getting stress tests if it hadn't become a bank holding company last year, ahead of receiving government assistance. It's helped by deep connections to Washington; former CEO Hank Paulson, pictured above, was Treasury secretary when the bailout program was designed.

Stress level: low. No need to raise more capital.

Analysis: Goldman Sachs may have the strongest and cleanest financial position among its peers, thanks to a capital infusion from Warren Buffett and the tens of billions of taxpayer dollars pumped into American International Group. That allowed AIG to make good on the billions of dollars worth of derivative insurance it had sold to Goldman Sachs. Goldman also recently raised $5 billion by issuing new stock.

Key challenges: A chief concern seems to be paying back government loans ahead of schedule. That would free Goldman from government and public meddling in key matters such as strategy and executive pay.

The bank: Morgan Stanley, an investment bank and asset manager, finds itself among the retail banks getting stress tests only because it converted to a bank holding company last year.

Stress level: medium to low. Morgan Stanley needs to raise $1.8 billion in additional capital.

Analysis: CEO John Mack, pictured above, has had to fight for his job, but Morgan Stanley has decent financial strength. It recently added to capital, and it has been trimming risk. However, below-average operating income and poor return on equity set off alarm bells at research shop Institutional Risk Analytics.

Key challenges: Morgan Stanley has taken big write-downs on toxic assets, and further write-downs may be in store if the economy worsens. Compared with its peers, the bank's trading revenue was surprisingly weak in the first quarter, contributing to a loss.

The bank: Represented by Snoopy in ad campaigns, MetLife offers a range of insurance products that aim to keep customers as carefree as the famous comic-strip pooch. The insurer offers life, auto and homeowners policies, and retirement products such as annuities. MetLife's vast size -- it serves 13 million households -- helps it keep costs low so it can undercut smaller rivals on price. Though it's chiefly an insurer, MetLife has technically been a bank holding company since 2001.

Stress level: low. Regulators found no need to raise additional capital.

Analysis: MetLife is so confident in its financial strength that it declined to participate in the Troubled Asset Relief Program. The insurer raised $2.3 billion in a stock offering in October. And it "generates sufficient operating cash to comfortably service its debts," Morningstar analyst Alan Rambaldini says.

Key challenges: Like many insurers, MetLife is getting squeezed because it faces losses on investments while it still has to meet guaranteed payouts on annuity policies.

The bank: Based in Pittsburgh, PNC Financial Services Group offers retail and commercial banking and asset management services in the Midwest and Northeast. It also owns a big stake in BlackRock, an investment company.

Stress level: low. Needs to raise $600 million in additional capital.

Analysis: PNC has avoided most of the subprime mess. It also picked up troubled National City, a Cleveland bank, on the cheap last year and says benefits from the merger helped first-quarter results.

Key challenges: Managing the rest of the integration of National City will be tricky. Plus, PNC operates in the depressed Rust Belt, so credit losses will mount as the recession grinds on.

The bank: US Bancorp operates banks throughout the Midwest and West, and it gets fairly reliable fee income from its asset management and payment processing businesses.

Stress level: low. Regulators found no need to raise additional capital.

Analysis: The bank has solid financial strength. Prudent loan underwriting kept it from growing too fast during the bubblier years, so charge-offs are now lower.

Key challenges: US Bancorp does have a sizable residential mortgage and home equity loan book and exposure to California, where the housing market is particularly bad. So losses will mount if the economy worsens. But the bank is gaining share from troubled competitors.

The bank: Formed by the 2007 marriage of Bank of New York and Mellon Financial, Bank of New York Mellon provides back-office custody services to other financial companies and manages assets for the wealthy in a private banking arm.

Stress level: low. Regulators found no need to raise additional capital.

Analysis: The bank wants to be among the first to pay back money received through the Troubled Asset Relief Program. But it still has exposure to the mortgage mess and large, highly leveraged fixed income and stock positions. So an extended market slide could force the bank to raise more capital, Morningstar analyst Michael Kon says.

Key challenges: Its biggest issues are exposure to the home mortgage mess and its big market positions. Plus, the bank is still working through its integration with Mellon Financial and a corporate trust business obtained from JPMorgan Chase.

The bank: Formerly an arm of General Motors, GMAC Financial Services offers auto and mortgage financing. It is now jointly owned by GM and private investors, including Cerberus Capital Management.

Stress level: high. Regulators told it to raise $11.5 billion in new capital.

Analysis: GMAC has been hit hard by huge losses in both its mortgage and auto loan businesses. It has $30.6 billion of debt maturing this year.

Key challenges: GMAC converted to a bank last year, and it has received $5 billion in bailout money through the Troubled Asset Relief Program. But it faces continuing losses at its auto finance and mortgage units at a time when it is still squeezed for capital. GMAC could get some breathing room by raising as much as $12 billion from debt guaranteed by the Federal Deposit Insurance Corp.

The bank: SunTrust Banks is a "superregional" bank with more than 1,600 branches in the Southeast.

Stress level: low. Told to raise $2.2 billion.

Analysis: SunTrust believes it is strong enough to pay back its $4.9 billion in TARP money as soon as possible, and analysts seem to agree. SunTrust gets high scores from research shop Institutional Risk Analytics.

Key challenges: The bank has significant exposure to low-quality residential mortgage loans in Florida, one of the worst states for the mortgage mess.

The bank: Thanks to clever marketing campaigns, Capital One Financial is one of the most recognized brands in financial services. The bank is one of the top five credit card issuers and auto lenders in the U.S.

Stress level: medium to low. Regulators found no need to raise new capital.

Analysis: Capital One looks well-capitalized, but it gets a "C" for operating performance from research company Institutional Risk Analytics.

Key challenges: Rising unemployment could create more loan losses, and recession-induced consumer frugality does not bode well for growth. Another major headache: possible relaxation of the rules surrounding personal bankruptcy.

The bank: Fifth Third Bancorp is a sizable Midwestern bank with a big presence in Ohio and Michigan and branches reaching as far as South Florida.

Stress level: medium. Regulators told it to raise $1.1 billion in capital.

Analysis: Fifth Third has a strong capital base. But it gets an "F" from research company Institutional Risk Analytics for poor operating performance, including a troublingly low return on equity and above-average loan defaults.

Key challenges: Bad loans in Michigan and Florida, both particularly hard-hit by the economic downturn, are weighing on Fifth Third. The bank may have to boost its capital cushion in ways that harm current stockholders, Morningstar analyst Maclovio Pina says.

The bank: KeyCorp, based in Ohio, operates community banks in the Great Lakes region, the Northeast and the Rockies.

Stress level: medium. Told to raise $1.8 billion in new capital.

Analysis: KeyCorp has decent capital levels, but it gets an "F" from research shop Institutional Risk Analytics for poor operating performance, including a weak return on equity and high loan defaults.

Key challenges: KeyCorp has big exposure to residential construction, auto, boat and RV loans in areas of the country particularly hard-hit by the recession, including Michigan, Ohio and western Pennsylvania.

1. American Express: Still strong

The bank: Known around the world for its green charge card, American Express operates a closed-loop credit card network in the U.S. that allows it to keep all profits for itself.

Stress level: low. Regulators found no need to raise new capital.

Analysis: American Express has solid financial strength, and it's been keeping up with cost-cutting and reserves against bad loans as the downturn hits its business.

Key challenges: AmEx will continue to get hit if the economy worsens, and any relaxation of the rules on personal bankruptcy would hurt the company.

2. BB&T: Attractively conservative

The bank: BB&T is a large regional bank operating in the Southeastern U.S.

Stress level: low. Regulators found no need to raise new capital.

Analysis: BB&T has a conservative balance sheet and plenty of capital. It's taking market share as more customers bank with it because they think it is safer.

Key challenges: Loan charge-offs and nonperforming assets jumped significantly in the first quarter and will probably worsen as the recession drags on.

3. Regions Financial: Results need improvement

The bank: Based in Birmingham, Ala., Regions Financial is a big regional bank in the Southeast, and it has a brokerage arm called Morgan Keegan.

Stress level: medium. Told to raise $2.5 billion in new capital.

Analysis: Regions Financial has decent capital strength, but poor operating results bring down its overall score, research company Institutional Risk Analytics says.

Key challenges: Regions Financial has a large presence in Florida, where home mortgage and condo loans continue to turn sour at an alarming rate -- one reason Morgan Stanley analyst Betsy Graseck has an underweight rating on the stock.

4. State Street: Uncertain risks

The bank: State Street offers back-office services to other financial companies and asset management services.

Stress level: low. Regulators found no need to raise new capital.

Analysis: State Street is improving its capital strength, but it is still highly leveraged.

Key challenges: State Street has off-balance-sheet investment vehicles with exposure to mortgage-backed securities. If those assets continue to depreciate and State Street is forced to bring them on its books, it will need more capital, Morningstar says.

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