The NFL uses two different measures to designate a player’s level of service: accrued and credited seasons.
Accrued seasons: Used to determine a player’s free agency status (unrestricted, restricted, exclusive rights). In order to accrue a season, a player must have been on (or should have been on*) full-play status for at least six regular-season games in a given season. A player under contract must report to his team’s training camp on his mandatory reporting date in order to earn an accrued season. If player holds out his services for a “material period of time,” he is also at risk of not accruing a season.
*When I write “or should have been on,” note that this is the language used in the CBA. Basically, in order to accrue a season, the player needs to be on the team’s active/inactive list, injured reserve or reserve PUP for at least six regular-season games in a given season.
Credited seasons: Used as a measure for many benefits, it’s most notably utilized to determine a player’s minimum salary. To earn a credited season, a player must be on (or should have been on) full-pay status for a total of three or more regular season games.
Minimum salaries in 2020 based on Credited Seasons (CS):
0 CS: $610,000
1 CS: $675,000
2 CS: $750,000
3 CS: $825,000
4-6 CS: $910,000
7+ CS: $1,050,000
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