The 2025–26 NCAA Division I men's basketball season began on November 3, 2025. The regular season ended on March 15, 2026, with the 2026 NCAA Division I men's basketball tournament beginning with the First Four on March 17 and ending with the championship game at Lucas Oil Stadium in Indianapolis, Indiana, on April 6.

Rule changes On May 9, 2025, the NCAA Basketball Rules Committee proposed a few rule changes for the 2025–26 and 2026–27 seasons. These changes were approved on June 10 by the NCAA Men's Basketball Rules Committee and the Playing Rules Oversight Panel. If one of the shot clocks becomes inoperable, the shot clock at the other basket will remain on. Headbands up to 4 inches wide will be allowed. Continuous motion rule: an offensive player who ends his dribble going toward the basket and absorbs contact from the defense will be permitted to pivot or complete the step the player is on and finish the field goal attempt. Officials will have the option to call a flagrant 1 foul when a player is contacted to the groin. Bench personnel who physically assist a player with the ball will be penalized if they intentionally interfere (i.e., assisting a player to stay inbounds when their momentum is taking them out of bounds, pushing a player in a direction the coach wants the player to go). All fouls or violations below the free throw line extended in a team's frontcourt will result in throw-ins at the nearest-designated spot under the basket and all fouls or violations above the free throw line extended will result in throw-ins at the nearest-designated spot at the 28’ foot mark. If a player uses the backboard or rim to gain an advantage, it will be a basket interference violation. Musical instruments, amplified music, canned music or artificial noisemakers will be permitted during dead balls. A one-game suspension will be required for an individual who failed to serve a suspension for physical abuse of an official or fighting, and a one-game suspension for the team's head coach will be required when the individual who should have served their suspension failed to do so. A coach's challenge will be permitted at any point in a game to review out-of-bounds calls, basket interference/goaltending and whether a secondary defender was in the restricted area arc.

On December 18, 2024, a United States District Court issued a preliminary injunction in favor of Vanderbilt quarterback Diego Pavia after preliminarily finding that NCAA Division I by-laws 12.02.06 and 14.3.3 and the rules in the NCAA Division I 2024–25 Manual constitute a commercial agreement, can be replaced by a less restrictive alternative and cause irreparable harm to Pavia. The injunction prevents the NCAA from enforcing its eligibility rules against Pavia and Vanderbilt University. The injunction is not a final determination of the judicial system as to the NCAA's eligibility rules and specifically applies only to Pavia. Nevertheless, the NCAA Division I board of directors approved a temporary blanket waiver for student-athletes who competed at a non-NCAA school for one or more years and would have exhausted their NCAA eligibility following the 2024–25 academic year under existing rules. Such student-athletes are granted an additional year of eligibility for the 2025–26 academic year.

Season headlines May 6 – New Haven announced that it accepted an invitation to join the NEC effective July 1, 2025, and begin reclassification from NCAA Division II to be eligible for NCAA-sponsored postseason play in 2028–29. June 4 – Utah Valley announced that it would join the Big West Conference from the Western Athletic Conference (WAC) in 2026–27. June 18 – Sacramento State announced it would join the Big West Conference from Big Sky Conference in 2026–27. June 25 – Southern Utah and Utah Tech announced they would join the Big Sky Conference from the WAC in 2026–27. June 26 – The Atlantic Sun Conference (ASUN) and the Western Athletic Conference (WAC) announced a strategic alliance under which the WAC will rebrand as the United Athletic Conference (UAC) beginning with the 2026–27 academic year. The rebranding will allow the continuing conference to retain the WAC’s automatic qualification status for NCAA championship events, including basketball. Under the announced alignment: The rebranded all-sports UAC will include the three remaining WAC institutions—Abilene Christian and Tarleton State, and non-football UT Arlington. The five ASUN members that play football in the UAC—Austin Peay, Central Arkansas, Eastern Kentucky, North Alabama, and West Georgia—will also join the all-sports UAC. Going forward, the ASUN will retain its seven current members that do not play scholarship FCS football. Five of these schools do not sponsor football at all, Stetson plays non-scholarship FCS football in the Pioneer Football League, and Bellarmine plays the non-NCAA variant of sprint football. June 30 – Texas State announced it would join the Pac-12 Conference from the Sun Belt Conference in 2026–27. July 15 – Louisiana Tech announced it would replace Texas State in the Sun Belt Conference (SBC) from Conference USA (CUSA). Louisiana Tech will join the Sun Belt no later than July 1, 2027. July 21 – The American Athletic Conference announced it had dropped the word "Athletic" from its name, becoming the American Conference. The conference also retired the "AAC" initialism, which had been used more by media than by the conference itself; the official short form is now simply the word "American". August 13 – Tennessee Tech announced it would join the Southern Conference from the Ohio Valley Conference (OVC) in 2026–27. September 3 – UC San Diego announced it would join the West Coast Conference (WCC) from the Big West Conference in 2027–28. September 24 – The Loyola Phoenix, the student newspaper of Loyola University Chicago, announced that 106-year-old Sister Jean, who began her tenure at Loyola in 1991, and had been chaplain of the men's basketball team since 1994, retired for health reasons. October 2 – The Northeast Conference adopted its longstanding abbreviation of NEC as its official name. October 9 – Loyola Chicago announced that Sister Jean, the former basketball team chaplain who first came to prominence during the Ramblers' run in the 2018 NCAA tournament, died at age 106. October 10 – Little Rock announced that it would leave the OVC for the UAC in 2026–27. October 20 – The Associated Press named its preseason All-America team. The only unanimous selection, and also the only guard on the team, was Purdue's Braden Smith. The other honorees were Texas Tech forward JT Toppin, Michigan forward Yaxel Lendeborg, BYU forward AJ Dybantsa, and Florida forward Alex Condon. October 31 – The WCC announced that Denver would join from the Summit League in 2026–27. January 14, 2026 – At the annual NCAA convention, the Division I Cabinet approved changes to the transfer portal for several sports, including men's and women's basketball. Effective immediately: A single 15-day portal was adopted for all D-I teams, opening the day after the final game of the NCAA tournament. For players on teams undergoing a head coaching change, the portal will open for 15 days, starting 5 days after a new head coach is hired or publicly announced. If 30 days pass without the announcement of a new head coach, the portal will open for those players on the 31st day, as long as it falls after the championship game. This additional window is available only after the start of the standard portal. Midyear transfers will not be eligible to play for their new school during that season if they were enrolled at an NCAA member institution during the first academic term, regardless of whether they competed. March 5 – After several months of failed negotiations between Louisiana Tech and CUSA over the school's terms of departure, the University of Louisiana System, of which Tech is a member, filed suit against CUSA on Tech's behalf in Lincoln Parish. The suit sought to allow Tech to join the SBC on the school's desired July 2026 schedule. March 16 – Aden Holloway, Alabama's second-leading scorer, was arrested on two drug-related felony charges. He was removed from the campus pending a university investigation, and Alabama played the NCAA tournament without him. Charging documents indicated that nearly a kilogram of marijuana was seized from his apartment. April 2 – West Florida announced that it accepted an invitation to join the Atlantic Sun from the Gulf South effective July 1, 2026, and begin reclassification from NCAA Division II to be eligible for NCAA-sponsored postseason play in 2028–29.

Milestones and records During the season, the following players reached the 2,000-career-point milestone: Indiana swingman Tucker DeVries, Gonzaga forward Graham Ike, Oklahoma guard Nijel Pack, Kansas State guard PJ Haggerty, SMU guard Jaron Pierre Jr., Ohio State guard Bruce Thornton, SMU guard Boopie Miller Texas guard Tramon Mark, and West Virginia guard Honor Huff. November 3 – Houston coach Kelvin Sampson earned his 800th career win following the Cougars' win in their season opener against Lehigh. The victory was also Sampson's 300th during his tenure at Houston. November 16 – Purdue coach Matt Painter earned his 500th career win following the Boilermakers' 97–79 win over Akron. November 25–26 – Michigan became the first team to achieve consecutive victories of 30 points or more against ranked opponents with back-to-back wins over Auburn (21) and Gonzaga (12). December 13 – Arizona became the fastest team to achieve victories over 5 ranked opponents in a season, doing so in their 9th game of the season with victories over Florida (3), UCLA (15), UConn (3), Auburn (20), and Alabama (12). December 16 – Duke coach Jon Scheyer surpassed Vic Bubas to become the fastest coach to reach 100 career wins in ACC history. January 3, 2026 – Purdue guard Braden Smith (893) surpassed former Michigan State guard Cassius Winston (890) to become the Big Ten's all-time leader in assists after he recorded 12 of them in their 89–73 road victory at Wisconsin. January 24 – St. John's coach Rick Pitino became just the fourth coach to earn 900 career wins after an 88–83 comeback road win at Xavier, who were led by his son Richard. January 28 – Southern Illinois coach Scott Nagy earned his 600th career win following the Salukis' 65–50 win over Northern Iowa. February 18 Arkansas true freshman guard Darius Acuff scored 49 points, the most by a freshman against a then-AP ranked team in men's college basketball history, on the road at then-#25 Alabama in Tuscaloosa in a 115–117 double overtime loss for the Razorbacks. Butler coach Thad Matta earned his 500th career win following the Bulldogs' 93–89 win at Georgetown. March 6 – #19 Miami (Ohio) defeated Ohio 110–108 in overtime to cap a perfect 31–0 undefeated regular season. Miami became just the third team in men's Division I basketball history to enter a conference tournament 31–0, joining 2013–14 Wichita State and 2014–15 Kentucky, according to ESPN Research. March 7 – Ohio State guard Bruce Thornton (2,110) became the all-time leading scorer in school history, surpassing Dennis Hopson (2,096) after scoring 25 points in a 91–78 win over Indiana. March 9 – Santa Clara coach Herb Sendek earned his 600th career win after the Broncos beat Saint Mary's, 76–71, in the semifinals of the WCC tournament. March 13 – Following a 78–68 win over Seton Hall in the semifinals of the Big East tournament, St. John's became the eighth college basketball program in history to earn 2,000 all-time wins, joining Kansas, Kentucky, North Carolina, Duke, UCLA, Temple, and Syracuse.