Citigroup Inc. ( , ), operating as Citi, is a major American financial services company based in New York City, formed from the merger of Citicorp and Travelers Group on April 7, 1998. According to Forbes Global 2000 in March 2007, it is the largest company in the world with total assets of US $2.4 trillion (as of Sept 2007) The company employs 332,000 staff around the world, and holds over 200 million customer accounts in more than 100 countries. It is a primary dealer in US Treasury securities and its stock has been a component of the Dow Jones Industrial Average since March 17, 1997.

Its largest shareholders include Abu Dhabi Investment Authority of United Arab Emirates, Kingdom Holding Company owned by Prince Al-Waleed bin Talal of Saudi Arabia and Government of Singapore Investment Corporation.

On December 11, 2007, Vikram Pandit was named Citigroup's CEO, while Sir Win Bischoff was named chairman. Charles Prince, the Chairman and CEO, had resigned on November 4, 2007. Between that time, Bischoff had served as interim CEO while Robert Rubin was chairman of the board.