Charles Leo Fairbanks (June 10, 1933 – April 2, 2013) was an American football coach who was a head coach at the high school, college and professional levels. He served as the head coach at the University of Oklahoma from 1967 to 1972 and at the University of Colorado from 1979 to 1981, compiling a career college record of 59–41–1 (.589). Fairbanks was also the head coach for the New England Patriots of the National Football League (NFL) from 1973 to 1978, amassing a record of 46–41 (.529), and for the New Jersey Generals of the United States Football League (USFL) in 1983, tallying a mark of 6–12.

Born in Detroit, Fairbanks graduated from Charlevoix High School in 1951 and Michigan State University in 1955, following three years of varsity football with the Spartans under head coaches Biggie Munn and Duffy Daugherty. That fall, he began the first of three years as head coach of Ishpeming High School in Michigan's Upper Peninsula.

In 1958, he accepted an assistant coaching position at Arizona State University in Tempe, spending four years there under former Spartan teammate Frank Kush before moving on for another four-year stint at the University of Houston under Bill Yeoman from 1962 to 1965. In 1966, he accepted an assistant coaching position at the University of Oklahoma in Norman.

Following the unexpected death of 37-year-old Sooner head coach Jim Mackenzie in April 1967, Fairbanks was promoted to head coach four days later at age 33. He had nearly left for another assistant position at Missouri under Dan Devine, but decided to stay in Norman when Mackenzie moved him to offensive coordinator after the 1966 season.

Over the next six years, Fairbanks led Oklahoma to three Big Eight Conference titles, with 11–1 records in each of his final two seasons. Three months after his mid-contract departure to the New England Patriots of the NFL, Oklahoma was forced to forfeit nine games from the 1972 season after evidence of recruiting violations involving altered transcripts of student-athletes surfaced. Fairbanks denied any knowledge of this. The scandal under his watch made Sooners ineligible for bowl games or the UPI national championship for two years after he left.

After Fairbanks' departure from Oklahoma, his successor, Barry Switzer (coincidentally, Switzer interviewed for the vacant Michigan State head coaching position before Fairbanks departed Norman), won national titles in 1974 and 1975 with teams that were still on NCAA probation. Oklahoma claimed the national title in 1974 despite not being allowed to participate in a bowl game, and repeated in 1975 without a television appearance.

On January 26, 1973, Fairbanks was named head coach of the New England Patriots of the National Football League (NFL). His first NFL draft that year included John Hannah, Sam Cunningham, Ray Hamilton, and Darryl Stingley, the first of a solid run of drafts through Fairbanks' tenure with the team. After the Patriots went 5–9 in his first year, the 1974 season was marred by a league-wide players' strike during training camp and preseason, which actually helped the Patriots as Fairbanks and defensive coordinator Hank Bullough were installing a new system (today known as the Fairbanks-Bullough 3–4, or the 3–4 two-gap system). They got a lot done because so many players who were not part of the NFL Players' Association, and eighteen first-year players made the roster. The Patriots stormed to a 6–1 start before other teams caught up with them and they finished 7–7.

Fairbanks then had a falling-out with quarterback Jim Plunkett, who was traded (in April 1976) for important draft picks to San Francisco, and suffered when hardball negotiating tactics by Patriot ownership led to a team-wide player strike that cancelled a preseason game with the New York Jets. The team never recovered and fell to 3–11 in 1975, but Fairbanks planted an important seed for the future by drafting quarterback Steve Grogan, who saw his first serious game action later that year.