Progressive jackpot

A progressive jackpot is a jackpot for a gaming machine (usually a slot machine or video poker machine) where the value of the jackpot increases a small amount each game (unless the player wins the jackpot). Normally multiple machines are linked together to form one large progressive jackpot that grows more quickly because multiple players are contributing to the jackpot at the same time. Many lotteries also feature progressive jackpots.

The amount of the jackpot is shown on a meter as a money value. Usually the jackpot can only be won by winning the combination with the highest payoff, e.g. a royal flush at a video poker game, or five of the most valuable symbols (lemons, cherries, alligators, etc.) on a slot machine. Once a player wins the jackpot, the jackpot resets to a preset minimum level.

The amount on the jackpot progresses (increases) a small amount for every play on a connected machine. The amount that the jackpot advances by is set by the casino ("the house"). For example, on a machine whose house edge is 5%, a generous jackpot contribution might be 1% (one fifth of the expected profit). The house is prepared to contribute some of the profit of a jackpot linked machine because players are attracted by the:

Usually only players who wager the maximum number of credits per play qualify to win the jackpot. All wagers, whether or not they are maximum credit bets, contribute to the jackpot though. As a result, a game which requires a 10 credit wager to qualify for the progressive jackpot will tend to have the progressive jackpot rise to higher levels (relative to its break-even level) than a game that requires only a 5 credit wager to qualify.

In some games such as video poker, blackjack, or Caribbean Stud Poker, it is possible to compute an optimal playing strategy based on the frequency for each payoff versus the odds of hitting that payoff. Since the jackpot of a progressive game is constantly growing, it eventually can reach a break-even point where the jackpot wager becomes a positive expectation bet for the player with a return to player (RTP) of greater than 100%. When the progressive jackpot is less than the break-even point, there is a negative expected value (house edge) for all players.

In the long run, with optimal strategy, a player can make a profit by only playing progressive games when their jackpots are above the break-even point, although the "long run" is generally longer than most people think (several tens of thousands of plays).

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Wikipedia