Swarthmore College (/ˈswɔːrθmɔːr/ SWORTH-mor, locally /ˈswɑːθmɔːr/ SWAHTH-mor) is a private liberal arts college in Swarthmore, Pennsylvania, United States. Founded in 1864, with its first classes held in 1869, Swarthmore is one of the earliest coeducational colleges in the United States. It was established as a college under the Religious Society of Friends. By 1906, Swarthmore had dropped its religious affiliation and officially became non-sectarian.

Swarthmore is an exclusively undergraduate four-year institution. It is a member of the Tri-College Consortium, a cooperative academic arrangement with Bryn Mawr College and Haverford College. Swarthmore is also affiliated with the University of Pennsylvania through the Quaker Consortium, which allows students to cross-register for classes at all four institutions.

Swarthmore's alumni include six Nobel Prize winners, 13 MacArthur Foundation fellows, as well as winners of the Tony Awards, Grammy Awards, Academy Awards, Emmy Awards, and the Guggenheim Fellowship.

The name "Swarthmore" has its roots in early Quaker history. In England, Swarthmoor Hall near the town of Ulverston, Cumbria, (previously in Lancashire), was the home of Thomas and Margaret Fell in 1652 when George Fox, fresh from his epiphany atop Pendle Hill in 1651, came to visit. The visitation turned into a long association, as Fox persuaded the couple of his views. Swarthmore was used for the first meetings of what became known as the Religious Society of Friends (later colloquially labeled "The Quakers").

The college was founded in 1864 by Deborah Fisher Wharton, along with her industrialist son, Joseph Wharton, together with a committee of members of the Hicksite Yearly Meetings of Philadelphia, New York and Baltimore. It is the only college founded by the Hicksite branch of the Society of Friends: previous Quaker institutions, like nearby Haverford College, were Orthodox in their founding history. Swarthmore held its first classes in 1869 and Edward Parrish (1822–1872) was the first president. Lucretia Mott (1793–1880) and Martha Ellicott Tyson (1795–1873) were among those Friends who insisted that the new college of Swarthmore be coeducational. Edward Hicks Magill, the second president, served for 17 years. His daughter, Helen Magill, (1853–1944), was in the first class to graduate in 1873; in 1877, she was the first woman in the United States to earn a Ph.D.

In the early 1900s, the college had a major collegiate American football program during the formation period of the soon-to-be nationwide sport (playing Navy, Princeton, Columbia and other larger schools) and an active fraternity and sorority life. The 1921 appointment of Frank Aydelotte as president began the development of the school's current academic focus, particularly with his vision for the Honors program based on his experience as a Rhodes Scholar.

During World War II, Swarthmore was one of 131 colleges and universities nationally that took part in the V-12 Navy College Training Program, which offered students a path to a U.S. Navy commission.

Wolfgang Köhler, Hans Wallach, and Solomon Asch were noted psychologists who became professors at Swarthmore, a center for Gestalt psychology. Both Wallach, who was Jewish, and Köhler, who was not, had left Nazi Germany because of its discriminatory policies. Köhler came to Swarthmore in 1935 and served until his retirement in 1958. Wallach came in 1936, first as a researcher, also teaching from 1942 until 1975. Asch joined the faculty in 1947 and served until 1966, conducting his noted conformity experiments at Swarthmore.