Each year, the NFL awards additional compensation to its players above and beyond those players’ contracts. As stipulated in the Collective Bargaining Agreement between the league and the players’ union, each team receives a pool of $8.5 million to split up among its roster based on the players’ existing contracts and the number of snaps they saw on the field over the prior season.
These bonuses, which do not count against the salary cap, are proportional to playing time and inversely proportional to a player’s adjusted compensation for that season. In other words, a player gets more money when he plays more has a lower contract.