Stephen Girard (May 20, 1750–December 26, 1831) was an American philanthropist and banker.

He was born in Bordeaux, France, and became a sailor at the age of 13. By 1773 he was master and captain of a vessel operating between New York, New Orleans, and the West Indies. In 1777, as a result of British blockades of seaports during the American Revolutionary War, he engaged in a mercantile career in Philadelphia. From 1780 to 1790 he resumed maritime trade with the West Indies, in partnership with his brother John. He developed a large fleet of vessels that engaged in worldwide trade. His efficient business practices enabled him to rapidly build a sizeable fortune.

After the charter for the First Bank of the United States expired in 1811, Girard purchased most of its stock as well as the building in Philadelphia and opened his own bank, naming it the Bank of Stephen Girard, which was a principal source of government credit during the War of 1812. Towards the end of the war, when the financial credit of the U.S. government was at its lowest, Girard placed nearly all of his resources at the disposal of the government and underwrote up to 95 per cent of the war loan issue, which enabled the United States to carry on the war. After the war, he became a large stockholder in and one of the directors of the Second Bank of the United States.

At the time of his death, Girard was regarded as one of the wealthiest men in America and he bequeathed nearly his entire fortune to charitable and municipal institutions of Philadelphia and New Orleans, including an endowment for establishing a boarding school for male orphans in Philadelphia, which opened as the Girard College in 1848.