Colorado is leaving the Pac-12 to rejoin the Big 12, the school announced Thursday after holding a board of regents meeting to accept an invitation from its former conference.

"After careful thought and consideration, it was determined that a switch in conference would give CU Boulder the stability, resources, and exposure necessary for long-term future success in a college athletics environment that is constantly evolving," a joint statement from Colorado chancellor Philip DiStefano and athletic director Rick George said. "The Big 12’s national reach across three time zones as well as our shared creative vision for the future we feel makes it an excellent fit for CU Boulder, our students, faculty, and alumni."

The Big 12 voted unanimously on a conference call Wednesday to invite Colorado. Commissioner Brett Yormark issued a brief statement regarding the Buffaloes' return to the conference: "They're back."

The Buffaloes will re-enlist in the Big 12 in time for the 2024 season. With Texas and Oklahoma set to simultaneously depart for the SEC, Colorado's return will bring the league's total membership to 13 teams.

A longtime member of the Big 12 and its precursor, the Big Eight, Colorado joined the Pac-12 in 2011 amid widespread expansion across the Football Bowl Subdivision. This type of back-and-forth realignment by a single program is a rare occurrence in FBS history, most recently during Temple's two stints as a member of the Big East from 1991-2004 and again in 2012.

WHAT'S NEXT?: Pac-12's future in doubt after Colorado's departure

The latest expansion domino to fall comes amid widespread unease and discontentment among Pac-12 member schools over the conference's place in the Power Five leagues and the league's unsettled media-rights deals.

While the Pac-12 could move to replace Colorado in the coming months — the league said in a statement it would "embrace expansion opportunities" following the conclusion of its media rights deal — the program's departure deals a body blow to the embattled conference, which has fallen well off the pace set by the rest of the Power Five in terms of on-field success and projected annual revenue through the rest of the decade.

"I want to thank the Pac 12 Conference for the home it has provided to CU athletics for more than a decade," Colorado president Todd Saliman said in a statement. "We look forward to maintaining the many partnerships developed with our Pac 12 colleagues. The landscape of collegiate sports is ever-evolving, and the University of Colorado Boulder has determined the Big 12 is the best future fit for our athletic teams."

From the 1980s through the early 2000s, Colorado was a fixture in the Top 25 and one of the top programs in the country. The Buffaloes shared the 1990 national championship with Georgia Tech.

But the Buffaloes' success began to wane during the program's final years in the Big 12. After winning the conference championship in 2001 and division crowns in 2002, 2004 and 2005, Colorado went 21-38 in its final five seasons in the league.

The bottomed dropped out in the Pac-12. Colorado has posted just two winning seasons since joining the league in 2011, one coming during the COVID-abbreviated 2020 season.

The Buffaloes have regained some national traction under first-year coach Deion Sanders, and plenty of attention for the unique way Sanders has gone about reconstructing the roster heading into his debut.

This article originally appeared on USA TODAY: Colorado joining Big 12 confirmed after school votes to leave Pac-12