Citigroup's first-quarter earnings beat expectations on both profit and revenue thanks to improvements on loans and credit spreads, sending shares higher.
The third-largest U.S. bank by deposits said it earned $1.29 a share, against estimates of $1.17, with total revenue of $20.81 billion, better than estimates of $20.17 billion.
Shares climbed 1.7 percent after the report hit at 8 a.m. ET.
"Long-term investors I think would do very well in buying this stock," Gerard Cassidy, head of U.S. bank equity strategy at RBC Capital Markets, told CNBC's "Squawk Box." "This company, Citi, is going to continue to see improvement this year in credit quality as well as managing their operating expenses, and that's doing to drive earnings higher."
The quarter improved in the same period last year, which saw the company earn $1.11 a share.
"I think Citi has the most interesting upside of the top four banks," Christopher Whalen, analyst at Carrington Investment Services, told CNBC.
The top-line growth game from a 2 percent increase in Citicorp and 15 percent from Citi Holdings, the part of the company used to unwind the bad assets from the subprime mortgage collapse.
The results were lifted by the release of $652 million in loss reserves, of which $351 million was from the Citi Holdings portfolio that is largely composed of mortgage assets. These assets are tied to U.S. house prices, which have been rising.
The bank, which is reviewing some of its weaker operations around the world, said revenue from its securities trading and investment banking business rose 31 percent to $6.98 billion.
The profit contributed to an increase in Citigroup's Basel III Tier 1 common equity ratio, a key regulatory measure of capital, to 9.3 percent at the end of March from 8.7 percent three months earlier, the company said.
Citigroup's adjusted results exclude the impact of changes in value of debt and obligations of its trading partners.
Citigroup is the third large U.S. bank to report its quarterly results.
On Friday, JPMorgan Chase beat earnings expectations and increased its dividend but reported that its loan growth slowed and net revenue fell. Competitor Wells Fargo also topped earnings forecasts, but its net interest margins shrunk during the quarter.
—Reuters contributed to this report.