American Express (often referred to as AmEx) is a US financial services company that specialises in payment processing services. It was founded in 1850 and has headquarters in New York City. The company is one of the largest within the industry, accounting for approximately 15% of credit card transactions across the US, with over 54 million cards in circulation. AmEx also offers corporate banking services, charge cards, traveller’s cheques, and corporate and personal travel planning services. The company has over $198bn assets and operates in 110 countries worldwide, with 55 office locations. American Express stock is listed on the New York Stock Exchange and is a constituent of the S&P 500 and Dow Jones Industrial Average (DJIA) indices. Start spread betting or trading CFDs on our American Express share price.