Arena football is a variety of gridiron football designed to be played indoors. The game is played on a smaller field than American or Canadian football, designed to fit in the same surface area as a standard North American ice hockey rink, and features between six and eight players for each team playing at any given time depending on the league, resulting in a faster and higher-scoring game that can be played on the floors of indoor arenas. The sport was invented in 1981, and patented in 1987, by Jim Foster, a former executive of the National Football League and the United States Football League. The name is trademarked by Gridiron Enterprises and had a proprietary format until its patent expired in 2007.
Three leagues have played under official arena football rules: the Arena Football League, which played 32 seasons in two separate runs from 1987 to 2008 and 2010 to 2019; arenafootball2, the AFL's developmental league, which played 10 seasons from 2000 through 2009; and the China Arena Football League, which played two abbreviated seasons in 2016 and 2019 but was not directly affiliated with the now-defunct AFL. A 2024 reboot of the Arena Football League used the original league's rulebook with minor variations.
Through the late 1990s, the Arena Football League was the only league playing any variant of the sport designed for indoor play. A clarification limiting the scope of its patent allowed for competing indoor football leagues (sometimes known as arena leagues) to use the same size field and most other aspects of the game. Arena football is distinguished from the other indoor leagues by its use of large rebound nets attached to the side of each goalpost, which keep any missed field goal or overthrown ball in the field of play and allow the ball to remain live; the rebound nets were the only part of the patent that was upheld until it expired. As a result, some non-AFL arena leagues that formed after the patent expired like the National Arena League have used rebound nets, although they no longer do. Other leagues such as the Indoor Football League and American Indoor Football opt to not use them. The newest league, Arena Football One, used the rebound nets as they began play in 2025.
History Early history The first demonstration of football on a small field was actually played outdoors at the original open-air Madison Square Garden. Using nine-man sides, Pennsylvania defeated Rutgers 10–0 at the annual meeting of the Amateur Athletic Union on January 16, 1889. Two months later, on March 7, 1889, the first documented indoor football game was an exhibition between Pennsylvania and Riverton Club at the Philadelphia Academy of Music. Field dimensions for the 0–0 tie were no more than 200 feet long by 50 feet wide, and the exhibition was played at night under gas lamps.
Other early indoor games included two exhibitions at Madison Square Garden II in December 1890. Springfield YMCA Training School and a Yale Senior Class team played on December 12, 1890. James Naismith scored a touchdown for Springfield, though Yale won the exhibition 16–10. (Naismith's dissatisfaction with how football transferred to the indoor surface inspired him to develop the game of basketball a year later.Monseau, Jeffrey. James Naismith’s Life and Legacy: Celebrating 150 Years. Kansas University. Retrieved December 14, 2025.) The following day a second exhibition game was played, with Pennsylvania defeating Rutgers 20–12. The field at Madison Square Garden measured long and wide. In an exhibition at Tattersall's Pavilion in Chicago on December 16, 1893, Chicago defeated Northwestern 20–14 on a field smaller than regulation.
The first documented indoor regulation football games were those played at the Chicago Coliseum in the late 1890s. The first such game matched Michigan against Chicago on Thanksgiving Day 1896. The match was "the first collegiate game of football played under a roof." Adding to the novelty, as daylight turned to darkness, the field inside the Coliseum was lit with electric lighting. With seven acres of floor space, the sprawling Coliseum is believed to have not needed any compromises to accommodate an American football field. According to a newspaper account, the field grew dark in the second half, and play was halted for ten minutes to discuss whether play should continue. Play was resumed, and the lights were finally turned on after Michigan scored a touchdown. The press proclaimed the experiment in indoor football to be a success:
One thing at least was settled by the game, and that is, that indoor football is literally and figuratively speaking a howling success. The men had no trouble in catching punts, and football was played on its merits, without the handicaps of a wet field or a strong wind. Toward the end of the second half it got very dark, and the spectators were treated to a novelty in the shape of football by electric light."
Although both critically and commercially successful, the Coliseum was destroyed in a fire less than two years after its opening. It hosted only four games, and its replacement could not accommodate an American football field.
Later, at Madison Square Garden in 1902 and 1903, there were games known as the "World Series of Pro Football." The games were played on a 70-yard by 35-yard dirt field but otherwise adhered to outdoor rules. Poor attendance led to the tournament being discontinued after two years.
The Chicago Bears of the National Football League hosted an experimental game against their crosstown rivals, the Cardinals, after the 1930 NFL season, at the indoor Chicago Stadium. Two years later, poor weather conditions led to the Bears hosting the 1932 NFL Playoff Game against the Portsmouth Spartans (now the Detroit Lions) at the stadium. A dirt and tanbark field measuring 80 yards long (60 yards plus two ten-yard end zones) and 45 yards wide was constructed on the arena's floor. The Chicago Stadium games were notable for introducing several rule changes, including the introduction of hash marks to keep play away from spectators who were seated next to the field (much like modern indoor football), while goal posts were moved to the goal line. To compensate for the smaller field, teams were "penalized" 20 yards upon crossing midfield. (The Bears' official Web site goes further and claims that field goals were outlawed for the 1932 game.)
In 1930, the Atlantic City Convention Center constructed a nearly full-size indoor football field, and used it for one to three games a year during the 1930s; the stadium stopped hosting games in 1940 and did not resume hosting football games until 1961. In the 1960s, the Boardwalk Bowl, a post-season game involving small college teams, was contested at the convention center. The Bowl was an attempt to make Atlantic City more of a year-round resort in the pre-gambling era as opposed to a single-season one (the Miss America Pageant, also held at the center, likewise began as an attempt to extend the season beyond Labor Day). The Atlantic Coast Football League played its inaugural championship game at the convention center in 1962, but the game only drew 2,000 fans and the game would thereafter move to the home stadium of the team with the best regular season record. The Philadelphia-based Liberty Bowl game, which had been played at Municipal Stadium from 1959 to 1963, was moved into the Convention Center in 1964 for the contest between Utah and West Virginia. The game drew just over 6,000 fans, though, and the Liberty Bowl moved to Memphis the next year, where it has remained. Unlike modern indoor football, the size of the playing surface and hence the rules were essentially the same as in the standard outdoor game, with rules updated to deal with contingencies for what could happen indoors, such as a punt striking the ceiling. The end zones were slightly shorter—eight yards instead of the standard ten (coincidentally, the eight-yard endzone length is the standard in modern indoor football).
Arena Football League
While several attempts to create a true indoor football game have been made since shortly after American football was developed, the first version to meet with relatively widespread success and acceptance was devised by Jim Foster, a former executive of the United States Football League and the National Football League. He devised his game while watching indoor soccer, another game derived from a sport played outdoors. He worked on the game in the early 1980s, but put any plans for full development of it on hold while the United States Football League, an attempt to play traditional American football in a non-traditional (spring-summer) season, was in operation in 1983–1985. When the USFL ceased operations, Foster saw his opportunity. He staged a "test" game in Rockford, Illinois in 1986 and put together a four-team league for a "demonstration season" in the spring of 1987, with games televised on ESPN.
Foster had to adopt a field that would fit within the smaller playing surfaces found in most arenas and thus created a field that was identical in size to a standard North American ice hockey rink, . This resulted in the field being 50 yards long (half of the length of a standard American football field) with eight-yard end zones (which may, if necessary, be curved in the end zones as hockey rinks are), and the field being slightly over half as wide as a standard football field. Foster adopted short-pile artificial turfs (which were then standard) such as AstroTurf for the field because of its ability to be easily rolled up when the arena is being used for other sports.
Foster adopted a modified version of eight-man football. He also mandated a one-platoon system that required at least six players to play on both offensive and defensive downs. This had the added desirable effect of limiting team payrolls.
There were numerous other rules designed to help the offense and ensure high-scoring games: punting is banned; a team not likely to get a first down may only attempt a field goal. the placing of taut rebound nets at the ends of the playing surface alongside the goalposts. Kicked and passed balls bouncing off these nets remain in play. In the case of a pass, the ball is live only until it touches the ground, allowing for receptions and interceptions on the rebound. On an unsuccessful field goal attempt or kickoff, the ball remains in play unless it goes out of bounds or until the player recovering it is downed by contact or scores, so on kicking plays (except an extra point attempt) either team may attempt to gain possession of the ball and advance it, much as a blocked kick could be in the traditional outdoor game. Only kicked or passed balls touching the slack nets behind the goalposts are ruled dead at that point.
To further an offensive passing advantage over the defense, Foster also imposed strict restrictions on the defensive formation, mandating that all defenses were required to play a 3-2-Monster formation with three defensive linemen, two linebackers, two cornerbacks, and one safety. Linebackers were not permitted to blitz and were required to stay in boxes behind the line of scrimmage, while defensive linemen were hindered by restrictions that prevented them from using certain techniques to penetrate the offensive line. Quarterbacks and placekickers were exempt from the one-platoon system, allowing two key scoring positions to be more specialized. The AFL also adopted the USFL's concept of playing in the late spring and summer, since this is when most hockey and basketball arenas have the fewest schedule conflicts (only competing with touring stadium rock concerts). The spring schedule has since been adopted by virtually all other professional indoor leagues as of 2010.