As of February 2020 there are 39 chapters and six colonies of Triangle Fraternity active in the U.S.[2] The headquarters is located in Plainfield, Indiana in a historic building erected as a Carnegie library in 1912.

[3] Triangle was formed in the fall of 1906 by sixteen civil engineering juniors at the University of Illinois.

The date of incorporation has been designated as Founders' Day, and Triangle celebrates it every year at each chapter.

It shall carry out its purpose by establishing chapters that develop balanced men who cultivate high moral character, foster lifelong friendships, and live their lives with integrity."

Triangle Fraternity was founded on high ethical and moral ideals, and expects the men of the fraternity to follow a set Code of Ethics, which is as follows: As a member of Triangle, I recognize my obligation to: