Kelly was selected by the Bills in the first round of 1983 NFL draft and was taken fourteenth overall. He chose to sign with the Gamblers instead and did not play for the Bills until the USFL folded in 1986. Employing the "K-Gun" offense, known for its no-huddle shotgun formations, Kelly led one of the greatest NFL scoring juggernauts. From 1991 to 1994, he helped guide the Bills to a record four consecutive Super Bowls, although the team lost each game.
In 2002, Kelly was inducted into the Pro Football Hall of Fame, his first year of eligibility. His jersey number 12 is one of two numbers retired by the Buffalo Bills.
Kelly was born in Pittsburgh, Pennsylvania, and grew up about 60 miles to the northeast, in East Brady. He was a standout at East Brady High School and won all-state honors after passing for 3,915 yards and 44 touchdowns. After his senior year, Kelly played in the Big 33 Football Classic.
Kelly also played basketball in high school, scoring over 1,000 points with six 30-plus-point games. As a senior, he led East Brady to the basketball state semifinals and averaged 23 points and 20 rebounds.
Kelly wanted to play college football at Penn State University under Joe Paterno, but he was offered a linebacker scholarship instead of quarterback. He went to the University of Miami, where he played an important role in helping build the program into one of the nation's best. Kelly finished his career at Miami with 406 completions in 646 attempts for 5,233 yards and 32 touchdowns; he was inducted into the university's hall of fame in 1992.
Because of fellow quarterback John Elway's well-publicized reluctance to play for the Baltimore Colts, which chose him in the 1983 NFL Draft, Kelly's agent asked whether there were any teams he would not play for. Kelly, who disliked cold weather, listed the Minnesota Vikings, Green Bay Packers, and Buffalo Bills. He was pleased to see while watching the 1983 draft on television that the Bills did not select him as the 12th pick in the first round, but learned from his agent that the team had another first-round pick; the Bills chose Kelly as the 14th pick. Although Kelly at the time stated that he had expected the Bills to choose him, he later said, "You have to say those things ... I cried. (Laughs) I didn't really literally cry. I just had tears. I'm like, 'You got to be kidding me.'"
Although he believed that team owner Ralph Wilson would not bring in the right players to build a championship team, Kelly was resigned to playing for the Bills. While meeting with the team to negotiate his contract, however, a Bills secretary mistakenly let Bruce Allen, general manager of the rival United States Football League's Chicago Blitz, reach Kelly on the telephone; Allen persuaded Kelly to leave the meeting. Kelly later claimed that the USFL offered him his choice of teams because of the league's interest in signing quarterbacks. He signed with the Houston Gamblers, who played in the climate-controlled Houston Astrodome, and said, "Would you rather be in Houston or Buffalo?"
In two seasons in Houston leading offensive coach Mouse Davis's run-and-shoot offense, Kelly threw for 9,842 yards and 83 touchdowns, completing 63% with an average of 8.53 yards per attempt with 45 interceptions. He was the USFL MVP in 1984, when he set a league record with 5,219 yards passing and 44 TD passes. Kelly's USFL records eclipsed those of fellow league quarterbacks Doug Williams and Steve Young. When the Houston Gamblers folded, Kelly went to the New Jersey Generals and was slated as their starting quarterback. Kelly also appeared on a cover of Sports Illustrated while holding a Generals' helmet, but the league collapsed before he ever fielded a snap with the Generals. Kelly remained on good terms with Generals owner Donald Trump, who provided his family with lodging during Kelly's later health issues.
Kelly finally joined the Bills (who had retained his NFL rights) in 1986 after the USFL folded. He helped lead the Bills to four consecutive Super Bowl appearances (Superbowl XXV-Superbowl XXVIII) and six divisional championships from 1988 to 1995. Buffalo made the playoffs in eight of Kelly's 11 seasons as their starting quarterback. Kelly's primary 'go-to' wide receiver with the Bills, Andre Reed, ranks among the NFL's all-time leaders in several receiving categories. Kelly and Reed connected for 65 TDs during their career together trailing only the tandems of Peyton Manning and Marvin Harrison (112), Steve Young and Jerry Rice (85), Dan Marino and Mark Clayton (79), Peyton Manning and Reggie Wayne (69), and Drew Brees and Marques Colston (68) for touchdowns by an NFL quarterback and receiver tandem.
Kelly ran the Bills' "K-Gun" no-huddle offense, which was a fast-paced offense named after tight end Keith McKeller, that denied opposing defenses the opportunity to make timely substitutions (the NFL later changed the rules in response to this to allow opposing defenses time to change formations under no-huddle situations, but this applied only if the offense made personnel substitutions). This offensive scheme called for multiple formation calls in a huddle, so that after each play was completed, the Bills would eschew a following huddle, instead lining up for the next play where Kelly would read the defense and audible the play. This led to mismatches and defensive communication breakdowns and, in the 1990s, established the Bills as one of the NFL's most successful and dangerous offenses, instrumental in leading Buffalo to four consecutive Super Bowl appearances.
Kelly holds the 2nd all-time NFL record for most yards gained per completion in a single game (44), established on September 10, 1995 in the Bills' game against the expansion Carolina Panthers. He recorded an NFL-best 101.2 passer rating in 1990, led the league with 33 touchdowns passes in 1991, and made the Pro Bowl five times (1987, 1988, 1990, 1991, and 1992).
In his four Super Bowls, Kelly completed 81 of 145 passes for 829 yards and two touchdowns, with seven interceptions. His 81 completions are the fifth most in Super Bowl history behind Tom Brady, Peyton Manning, Kurt Warner and Joe Montana. In Super Bowl XXVI, he set a record with 58 pass attempts, and in Super Bowl XXVIII he set a record with 31 completions (this was later surpassed).
Kelly finished his 11 NFL seasons with 2,874 completions in 4,779 attempts for 35,467 yards and 237 touchdowns, with 175 interceptions, all of which are Buffalo records excluding the interceptions. He also rushed for 1,049 yards and seven touchdowns.
Including his time in the NFL and USFL, he finished with over 45,000 passing yards and 320 touchdowns. In 2001, the Buffalo Bills retired his number 12 jersey.
On August 3, 2002, Kelly was inducted into the Pro Football Hall of Fame. He was enshrined during the first year he was eligible and headlined a class that also featured John Stallworth, Dan Hampton, Dave Casper, and George Allen. Fellow Hall of Fame member and former head coach Marv Levy was Kelly's presenter at the ceremony.
Kelly devoted much of his post-football life to his son, Hunter James Kelly, who was diagnosed with globoid-cell leukodystrophy (Krabbe disease) shortly after his birth on February 14, 1997. Hunter died as a result of this disease on August 5, 2005, at the age of 8. This loss deeply affected Kelly.
To honor his son, Kelly established a non-profit organization in 1997: Hunter's Hope. Kelly's advocacy on behalf of Krabbe patients has increased national awareness of the disease. He and his wife Jill founded the annual Hunter's Day of Hope, which is held on February 14, the birthdays of both Jim and Hunter Kelly. The Hunter James Kelly Research Institute was founded at the University of Buffalo in 2004, where neuroscientists and clinicians are studying myelin and its diseases.
When Kelly was inducted into the Pro Football Hall of Fame in 2002, he dedicated his speech to Hunter. "It's been written that the trademark of my career was toughness," he said as he choked back tears. "The toughest person I ever met in my life was my hero, my soldier, my son, Hunter. I love you, buddy."
Kelly continues to reside in East Aurora, New York, with his wife Jill and their daughters, Erin and Camryn. He has several business ventures, including Hall of Fame Life Promotions, a promotional company that is committed to donating a percentage of all of its proceeds to the Hunter's Hope Foundation.
In 2011, Kelly founded Jim Kelly Inc. a company which produces the MyFanClip line of all purpose clips which bear sports team logos and other insignia. MyFanClip has licensing agreements with the NFL, MLB, NHL and NASCAR. Proceeds also benefit the Hunter's Hope Foundation.
Since 1988, Kelly has run a football camp for youths between the ages of eight to 18 at the Buffalo Bills facilities. It started with 325 campers in its first year, growing to over 500 campers a year. This camp provides teaching from experienced coaches and previous players from all over the country. Kelly also participates in various drills with the participants.
On June 3, 2013, Kelly announced that he has been diagnosed with squamous cell carcinoma, a form of cancer, in his upper jaw. He underwent surgery at a Buffalo hospital on June 7. Kelly reported to news outlets shortly after his surgery that the procedure was successful and he was now cancer-free. On March 14, 2014, after a follow-up test at the Erie County Medical Center, it was announced that Kelly's cancer had recurred, and that he would begin radiation and chemotherapy treatment. It was announced on August 20, 2014 that doctors could no longer find evidence of cancer.
On November 1, 2014, Kelly announced he had contracted MRSA within his bones, three months after being declared cancer-free. A few weeks after the announcement, Kelly said he was MRSA-free.
Kelly, along with Andre Reed, Bruce Smith, Thurman Thomas, and Scott Norwood, was the subject of the 30 for 30 film—Four Falls of Buffalo.
Two of Kelly's nephews, both the sons of his younger brother Kevin, have also played quarterback. Chad Kelly played college football at the Division I level for the Clemson Tigers and the Ole Miss Rebels and took part in the 2017 NFL Draft, in which he was selected last overall in the seventh round by the Denver Broncos, earning the honor of Mr. Irrelevant. Casey Kelly, Chad's younger brother, is still in high school and is scheduled to graduate in 2019.