The American College of Surgeons also has membership categories for Associate Fellows (provides an opportunity for surgeons who are beginning surgical practice and who meet specific requirements to assume an active role in the College at an early stage in their careers), surgical residents, medical students, and allied health care professionals who are not surgeons, but who interact with surgical patients.

As of 2008, total membership was over 75,000 including more than 4,000 members from outside the US and Canada, and more than 2,600 Associate Fellows. Fellows of the College are organized into 100 chapters. There are 65 chapters in the United States, 2 in Canada, 3 in Mexico, and 30 in other countries around the world.

The ACS elected its first black Fellow, Dr Louis T. Wright, in 1934.