The NFL's salary cap has more than doubled since 2011. As one would expect, the prices of star players have skyrocketed.

While a chunk of these big-money contracts have panned out, others have failed spectacularly. That has caused certain NFL teams to take on dead money to move on from these albatross deals, whether via release or trade.

NFL teams weren't always willing to eat large chunks of dead cap space. However, doing so to move on from sunk costs – or to capitalize on a player's trade value – has become more popular since the Philadelphia Eagles traded Carson Wentz during the 2021 NFL offseason.

What exactly is dead money in the NFL? Here's a definition and what to know about the accounting of NFL contracts.

Dead money – which is also known as "dead cap space" or simply "dead cap" – is a salary cap charge for a player no longer on a team's roster. Typically, it stems from guaranteed money already given to a player in the form of signing bonuses who is either released, traded or retires.

NFL rules allow signing bonuses, option bonuses and certain roster bonuses to be prorated for up to five years. While the sum of the bonus is usually paid up front, the team accounts for the bonus by evenly spreading it out over the duration of the contract to avoid taking a massive salary cap hit in the first season.