A mythical national championship (sometimes abbreviated MNC) is national championship recognition that is not explicitly competitive. This phrase has often been invoked in reference to American college football, because the National Collegiate Athletic Association (NCAA) does not sponsor a playoff-style tournament or recognize official national champions for the Football Bowl Subdivision (FBS). The relevant recognition before 1998 came from various entities, including coach polls and media ballots, which each voted to recognize their own national champions, and is similar to the newspaper decision used in early boxing matches. Starting in 1998, national champion recognition was determined by the Bowl Championship Series (BCS) until it was replaced by the College Football Playoff (CFP) in 2014; neither system has ever been sanctioned by the NCAA to determine the national champion.

College football

"Mythical national champion" is a term that has been used since at least 1920 for a championship won by an NCAA Division I football team, especially for titles won before the Bowl Championship Series (BCS) system began in 1998. Before the BCS, polls in which coaches and/or sportswriters voted, such as the AP, UPI, and USA Today polls, awarded championships. This led to seasons in which two or more teams could claim to have won the national championship. Due to this, the NCAA does not designate a national champion for the sport in its record book.

Since the 1930s, each top team has traditionally played a single postseason bowl game. The process of selecting a national champion during this time was complicated by the fact that the champions of major conferences were tied to specific bowls (for example, the Big 8 champion was tied to the Orange Bowl), and the top two teams in the nation often played in different bowls. A few bowls over the years featured a #1 vs. #2 matchup; one example was the 1987 Fiesta Bowl, played January 2 following the 1986 season.

Two attempts to annually crown a champion on the field were the Bowl Coalition (1992–94) and Bowl Alliance (1995–97). However, their effort to host a national championship was hampered by the lack of participation of the Pac-10 and Big Ten champions, who instead opted to play in the Rose Bowl.

The BCS was an improvement on the Bowl Coalition and Bowl Alliance because it included the Rose Bowl and the champions of what were then the nation's six most powerful conferences. It attempted to eliminate uncertainty by ranking college teams and inviting the top two teams at the end of the regular season to play in a championship game. These teams were determined by the BCS ranking formula, which itself used a combination of human voter polls and computer rankings. The process of selecting the two best teams for the BCS championship game had nonetheless resulted in controversy, which reached a head in 2003 when the AP poll refused to vote the BCS champions (LSU) as their national champions. Instead, the AP voted USC as national champions for the 2003 season. This resulted in disputes between which team was the real champion, and as a result, the 2003 BCS Champion is not unanimous. As a result of this controversy, the AP removed itself from the BCS formula in 2004. Furthermore, because of AP Poll policies, should a team under a postseason ban finish first in the AP Poll, the AP will recognise such team as the AP's national champion. The AP will also not recognize further penalties, which resulted in a vacated national championship in 2004 by most authorities, but the AP still recognizes USC (which was stripped by the NCAA of wins and the BCS committee of its championship) despite the Reggie Bush penalties.

Since the 2014 season, the College Football Playoff—in association with Division I FBS collegiate conferences and independent schools, along with six bowl games—has been played. Through the 2023 season, the CFP featured the top four teams (as selected by a thirteen-member committee) to play two semifinal bowl games followed by a CFP National Championship Game between the semifinal winners. However, the panel has been criticized for failing to recognize champions of conferences outside the power conferences for participation in the CFP or the New Year's Six games. Since the 2024 season, the CFP has featured 12 teams, selected by the same committee used in the competition's four-team era. The New Year's Six games now serve as the quarterfinal and semifinal sites, with each game hosting two quarterfinals and one semifinal in a three-year rotation.

At lower levels of play in college football, mythical national champion crowns also continue to exist, separate from NCAA and NAIA championships, in the form of the black college football national championship. This is competed for by teams from historically black colleges and universities (HBCUs). In the present day, the winner of this crown at the NCAA Division I FCS level is generally considered to be the winner of the Celebration Bowl, DI FCS's only bowl game.

College basketball

The national championship of collegiate basketball that is officially recognized by the main governing body for collegiate athletics in the United States, the NCAA, has been awarded to the champion of an annual national post-season tournament run by the NCAA since 1939. National post-season college basketball tournaments began in earnest with the NAIA national men's basketball championship in 1937, the National Invitation Tournament (NIT) in 1938, and the NCAA tournament in 1939.

The Official NCAA Men's Basketball Records Book lists title selections of pre-tournament era teams by the Helms Athletic Foundation.The Helms Athletic Foundation was founded in 1936 by Bill Schroeder and Paul Helms. The name was a misnomer, as there actually was no foundation in place to sustain the operation. Instead the organization was subsidized completely by the operations of Helms Bakery. Schroeder selected the foundation's national champion teams and made All-America selections in a number of college sports, including football and basketball. Schroeder also retrospectively selected national champions in college football dating from 1947 back to the 1883 season and in college basketball from 1942 back to the 1900–01 season. The Helms Foundation's Bill Schroeder named a national champion from 1901 to 1982, with his selections from 1901 to 1941 being named retroactively in 1943 and 1957. The Helms champion, for the years in which the NIT and NCAA post-season tournaments were played, reflected the winners of the 1938 NIT and 1939 NIT, as well as the winners for all years of the NCAA tournament except for 1939, 1940, 1944 and 1954. Most recently, the retroactive end-of-year Premo-Porretta Power Poll has provided the first national rankings of college basketball teams for the 1895–96 through the 1947–48 seasons. (No regular, recognized national polling took place prior to the establishment of the Associated Press poll and the coaches poll for college basketball prior to the 1948–49 and 1950–51 seasons, respectively.ESPN College Basketball Encyclopedia, pp. 526–27) The Premo-Porretta rankings were published in 2009 in the ESPN College Basketball Encyclopedia. The poll's top team selections differed from the results of the NCAA tournament in 1939, 1941, 1943, 1944, 1945, and 1947.ESPN College Basketball Encyclopedia, pp. 546–85

During World War II, from 1943 to 1945, the NCAA, NIT and Madison Square Garden cooperated to host "mythical national championship games" between winners of each year's NCAA and NIT tournaments in order to benefit the American Red Cross' War Fund. The series was described by Ray Meyer, coach of the losing 1945 DePaul team, as "the games for the national championship". The NCAA champion prevailed in all three games.

During the early years of the two tournaments, the NCAA and NIT competed against each other, giving rise to debate over their relative prowess. In 1939, the inaugural year of the NCAA tournament, the NIT was generally considered to be superior. During the 1940s, the relative status of the two tournaments was unclear, and thus some years produced disputed national championship claims. Some contemporary sources claim superiority for the NIT during this time. In 1943, in a shrewd competitive move the NCAA tournament began sharing Madison Square Garden with the NIT. In 1945, following victories by the NCAA champions over the NIT champions in the Red Cross games, The New York Times indicated that many teams who could potentially get bids to enter either tournament would probably choose the NCAA tournament "because it involves stronger competition." In 1950, City College of New York won both the NIT and the NCAA tournaments in the same season, coincidentally defeating Bradley University in the championship game of both tournaments and thereby united the titles.

In the 1952 Olympic Trials held immediately after the tournaments, NCAA champion Kansas defeated NAIA champion Southwest Missouri State in the collegiate semi-finals and then NIT champion La Salle in the collegiate final. Kansas lost to the AAU champion Peoria Caterpillars in the overall final.

After the fall-out from the 1951 gambling and point-shaving scandals, the NCAA tournament pulled out of Madison Square Garden. With conference champions and the majority of the top-ranked teams participating in it, the NCAA tournament since then came to be regarded as the more important post-season tourney and the sole determiner of the national championship, although following the taint of the gambling scandals, the NIT was still considered a quality tournament for some time afterward.Harrison, Don (2011). Hoops in Connecticut: The Nutmeg State's Passion for Basketball. The History Press, Charleston, SC. p. 54. . "[John] Egan was the Providence College Friars' first "name" recruit, the player who arrived with the most acclaim. And he delivered as a sophomore [in 1959], averaging a team-high 20.9 points en route to propelling the Friars to a fourth-place finish in the then-prestigious National Invitation Tournament at Madison Square Garden."Hurley, Bob (2013). Chasing Perfect: The Will to Win in Basketball and Life. Crown Archetype, New York, NY. p. 26. . "That St. Peter's team was the best team the school ever had. That team would go on to beat Duke in the National Invitation Tournament, back when the NIT was a big-time tournament." The NCAA built on the momentum of three consecutive Red Cross "mythical national championship" game victories over the NIT, eventually outmaneuvering the NIT by adeptly avoiding permanent damage from the 1951 gambling and point-shaving scandals and by adding more teams. As the NCAA tournament steadily gained prominence, it became the sole source of naming the national champion.

Schools that claim pre-NCAA tournament basketball championships

In some years college teams won playoff series or tournaments played on the court for a national championship, such as the annual AAU tournaments. In addition, many schools claim or recognize pre-tournament era national college basketball championships by virtue of being selected retrospectively by third-party selectors, such as Bill Schroeder at the Helms Athletic Foundation, including the Kansas, Purdue, Stanford, North Carolina, Pittsburgh, Wisconsin, Syracuse, and Washington State. LSU claims the 1935 championship by virtue of winning the American Legion Bowl game against Pittsburgh in a match-up of regional powers.