The conference was formed when the original Big 8 Conference (consisting of Oklahoma, Oklahoma State, Colorado, Nebraska, Kansas, Kansas State, Missouri, and Iowa State) merged with four Texas universities from the defunct Southwest Conference (SEC; the schools joining were Texas, Texas A&M, Texas Tech, and Baylor, the latter two were not originally slated to join but the Texas Legislature mandated it as a condition of Texas and Texas A&M joining).
Of the Power 5 conferences it has had the most turnover in terms of membership: six of its original member universities have left or are leaving for other conferences (Colorado to the PAC-12, Nebraska to the Big 10, and Texas A&M and Missouri to the SEC, with Texas and Oklahoma scheduled to also join the SEC no later than the 2025 season) while it has gained or will gain six new members (TCU -- also a former SWC member -- and West Virginia, with BYU, Central Florida, Cincinnati, and Houston -- another former SWC member -- slated to join at a future date). However, it has also been the most willing to accept a religious-based university into its membership: outside of ACC members Duke and Wake Forest -- which are only nominally affiliated with the Methodists and Baptists, respectively -- the Big 12 is the only other Power 5 conference to have religious-based universities as members (TCU -- though its affiliation with the Disciples of Christ is also now nominal -- and Baylor, along with future member BYU).
The most recent Big 12 team to win a national football championship was the University of Texas in 2006. The most recent national men's basketball championship among Big 12 teams was won by Baylor University in 2021. Historically prestigious basketball schools include Kansas and Oklahoma State, and Baylor in women's basketball having won three national titles.
- Baylor University in Waco, Texas
- Iowa State University in Ames, Iowa
- University of Kansas in Lawrence, Kansas
- Kansas State University in Manhattan, Kansas
- Oklahoma State University in Stillwater, Oklahoma
- Texas Christian University in Fort Worth, Texas
- Texas Tech University in Lubbock, Texas
- West Virginia University in Morgantown, West Virginia
- The "Power 5" conferences, a term designating the major conferences in college football, are (in addition to the Big 12) the Big 10, the PAC-12, the Southeastern (SEC), and the Atlantic Coast (ACC) conferences. Notre Dame, despite being an independent in football (it is affiliated with the ACC in all other sports), is also included in this grouping.