American Express Company (NYSE: AXP), sometimes known as "AmEx" or "Amex", is a diversified global financial services company that is headquartered in New York City, New York. Founded in 1850, the company also has major offices in Fort Lauderdale, Florida; Salt Lake City, Utah; Greensboro, North Carolina; Phoenix, Arizona; Sydney, Australia; Markham, Canada; and Brighton, United Kingdom. The company is best known for its credit card, charge card, and traveler's cheque businesses.

The company's common stock trades on the New York Stock Exchange under the ticker symbol "AXP." It is one of the 30 components of the Dow Jones Industrial Average. In 2007, BusinessWeek and Interbrand ranked American Express as the fourteenth most valuable brand in the world, estimating it to be worth US$20.87 billion.

On November 10, 2008, during the financial crisis of 2008, the company won Federal Reserve System approval to convert to a bank holding company, making it eligible for government help under the Troubled Assets Relief Program. At that time, American Express had total consolidated assets of about $127 billion.

American Express's chief executive officer is Kenneth Chenault, who took over in 2001.