What Is the Salary Cap
The NBA salary cap is a maximum amount of money that each team is allowed to spend on player contracts in a single season. The league sets this amount each year based on how much money the NBA made the previous season. Every team must follow this limit, though there are some special rules that allow teams to go slightly over it.
How the Amount Is Determined
The NBA calculates the salary cap by taking a percentage of the league's total basketball-related income from the previous year. This includes money from ticket sales, television deals, merchandise, and other sources. A certain percentage of this revenue is divided equally among all 30 NBA teams. This means if the NBA makes more money, the salary cap goes up the next season.
How Teams Use the Cap
Teams must add up all their players' salaries for the season and make sure the total does not exceed the salary cap. When a team signs a new player or trades for one, the player's salary counts toward that limit. Teams can release players to create more salary cap space if they need to sign other players.
Going Over the Cap
Teams are allowed to exceed the salary cap using special exceptions granted by the NBA. The most common is the mid-level exception, which lets teams sign players even if they are over the cap. However, teams that go too far over the cap must pay a luxury tax, which is a financial penalty. The luxury tax is money teams pay to the league when their total payroll exceeds a certain threshold.
Why the Salary Cap Matters
The salary cap helps keep the NBA competitive by preventing wealthy teams from simply buying the best players. Without a salary cap, rich teams could spend unlimited money on star players while smaller-market teams could not compete. The cap ensures that all teams have roughly equal resources to build their rosters, making the league more balanced and unpredictable. 
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