Jersey numbers have specific requirements under the rules of the NFL. This practice started in 1952, and it became more formal in 1973.
Each NFL jersey has a number on the front and back, and �TV numbers� are also visible on the sleeve or shoulder of each player. The last name of the player is required on the back of the jersey, and numbers are also sometimes included on the player�s helmet.
The following number system was put into place by the NFL in 1973. Numbers are based on the player�s primary position on the football team.
1 to 19 – Worn by kickers, punters and quarterbacks. Starting in 2004, wide receivers were also allowed to wear numbers between 10 and 19.
20 to 49 – Worn by running backs, tight ends, safeties and cornerbacks.
50 to 59 – Worn by linebackers and offensive linemen.
60 to 79 – Worn by both the offensive and defensive line.
80 to 89 – Worn by wide receivers and tight ends.
90 to 99 – Worn by linebackers and defensive linemen.
0 and 00 – No longer used after 1973.
The jersey numbers in college football are much different. Members of the offensive line who play an ineligible position must wear between 50 and 79. Otherwise, any number is possible, although lower numbers often hold greater prestige. Much of the reason for the difference is due to the fact that NCAA rules allow a college football team to carry 85 men on their roster, and the NFL numbering system would not be sufficient.