Every progressive is funded by a small slice of each qualifying stake, set in the game rules. When the jackpot is won, it drops back to a seed amount paid by the operator or the game maker, and the climb starts again. The slice set aside for the pot comes out of what the game would otherwise pay in regular wins, so the everyday prizes on a jackpot slot tend to be smaller than on a similar game without one.
Jackpots are won in one of two ways. Some need a specific combination, such as five jackpot symbols on a line at the maximum stake. Others are triggered at random after any spin, often through a jackpot wheel or a bonus game that picks one of several tiers. Random triggers usually give a larger stake a better chance of starting the jackpot game, a rule the game information states plainly in most titles.
Many jackpot games run several tiers at once, often labelled mini, minor, major and grand, with the smaller ones won far more often. Some tiers can only be won at a minimum stake or with an optional side bet switched on. Playing below the qualifying level still feeds the pot while leaving the top prize out of reach. The qualifying stake for each tier is listed in the game rules beside its current value.