Prior to 1973 The earliest numbering systems were significantly different from the modern variation. Until the 1920s, when the NFL limited its rosters to 22 players, it was rare to see player numbers much higher than 25 (
Red Grange was a notable exception, wearing 77 with the
Chicago Bears while playing
halfback, which would not be allowed under current NFL rules), and numbers had little correlation with positions (in 1929, the
Orange Tornadoes subverted the system even further, experimenting with using
letters instead of numbers). The numbering system used today originated when all teams employed some variation of the
single wing formation on offense. When teams switched to the
T-formation in the 1930s and 1940s, the numbers were taken with them to whichever position evolved from the old single wing position. This numbering system originated in college football and was used only informally in the NFL until 1952; the backs were given numbers in the 10–49 range and the offensive line numbers in the 50–89 range. Earlier, defensive players wore numbers that reflected their offensive position, as many players played both offense and defense. For example, quarterbacks and halfbacks usually played in the defensive back field and so had numbers in the 10–49 range, defensive line numbers ranged from 50–89, while linebackers (who often played fullback or tight end on offense) could have just about any number. Split ends (precursors to modern wide receivers) had numbers in the 80s, and many would play cornerback (e.g.,
Night Train Lane, who wore 81 as a cornerback). The
All-America Football Conference (AAFC) of the 1940s, which later merged with the NFL, had a different numbering system with quarterback in the 60–69 range (
Otto Graham), fullbacks in the 70–79 range (
Marion Motley), halfbacks in the 80–89 (
Don Greenwood) and 90–99 range (
Tommy Colella), ends in the 50–59 range (
Mac Speedie), tackles in the 40–49 range (
Lou Groza), guards in the 30–39 range (
Bill Willis), and centers in the 20–29 range (
Frank Gatski). When the AAFC merged with the NFL in 1950, the AAFC players kept their old uniform numbers, which caused confusion and resulted in the NFL going to a standard numbering system in 1952. This resulted in many star players having to change their numbers mid-career. Examples are
Otto Graham going from 60 to 14,
Norm Van Brocklin going from 25 to 11,
Marion Motley going from 76 to 36, and
Tom Fears going from 55 to 80. The
American Football League (AFL) of the 1960s, which also later merged with the NFL, used essentially the same numbering system as the NFL with some exceptions, mostly pertaining to wide receivers, who were allowed to wear numbers in the teens and 20s (as the AFL had a greater priority toward offense, the league often made use of flankers, receivers positioned in the backfield). The AFL's numbering system also allowed for the use of a double-zero as a number, which was used by future Hall of Fame player
Jim Otto, center for the
Oakland Raiders; after wearing the number 50 in his rookie season, he switched to 00 (which was said as 'aught, oh', a
homonym of Otto), which he wore for the remainder of his career.
1973 standardization The NFL imposed a more rigid numbering system in 1973. When it went into effect, players who had played in the league before the 1973 season were given a
grandfather clause to continue wearing their now-prohibited numbers.
Pro Football Hall of Fame wide receiver
Charlie Joiner was the last player covered by the clause, wearing number 18 through the
1986 NFL season, after which he retired (Under the current jersey system, Joiner's #18 would have been allowed for a wide receiver to wear). Joiner was also the last active player who began his career in the AFL. The last player to be grandfathered who wore a number that would not have been allowed under the current jersey system was
Julius Adams, who retired in 1985 wearing the number 85 as a defensive end, although Adams did return to play in 1987 wearing the number #69.
1973–2020 From 1973 to 2020, five major changes were made. In 1979, the NFL allowed defensive linemen to wear numbers 90–99 and centers 60–79. In 1984, the NFL allowed linebackers to wear jersey numbers in the 90–99 range, since more teams were making use of the
3–4 defense and thus were quickly exhausting numbers for linebackers, who previously were only allowed to wear numbers in the 50–59 range. Another change occurred in 2004, when the NFL allowed wide receivers to wear numbers 10–19 in addition to the previous 80–89 range; this was due to several NFL teams retiring 80-range numbers, as well as teams employing more receivers and tight ends in their offense.
2021–2023 expansions In 2021, NFL owners passed a rule expanding available numbers and simplifying the numbering system. The changes included allowing running backs, tight ends, fullbacks, H-backs and wide receivers to wear numbers 1-49 and 80-89; defensive backs were permitted to choose from 1-49; linebackers 1-79 and 90-99; offensive linemen 50-79; and defensive linemen 50-79 and 90-99. QBs, kickers and punters remained from 1-19. In 2023, a playing rule was passed allowing players to wear the jersey number 0, and kickers and punters were given eligibility to use numbers 20–49 and 90–99. ==Current system==