Progressive jackpots are a familiar sight at online casinos, with a prize that grows until someone wins it. The idea is simple, but a few terms help explain how the figure builds and how it is eventually awarded. This short glossary runs through the main ones in plain language, so the headline number is easier to put in context, and as with any gambling, local rules and responsible participation always apply.

The seed

A progressive jackpot usually starts from a base amount known as the seed. After the jackpot is won, it resets to this seed value and begins growing again from there. The seed is set by the game or the operator, and it is simply the floor from which the prize builds rather than any indication of what it will reach.

The contribution

The jackpot grows because a small part of each qualifying bet is added to the pool. This steady contribution is why the figure rises over time. It also means the amount on display reflects past play rather than a signal about when the prize will next be won, which is not something anyone can predict.

The trigger

A jackpot is awarded when a specific condition is met, which may be a random event or a particular combination, depending on the game. A plain rundown of how these work is available via View details. However it is triggered, the chance of it happening on any given spin is very small, and each spin remains independent of the one before it.

Pooled jackpots

Some jackpots are pooled across several games, or even several sites, which is how they can reach such large figures. A wider pool means more contributions feeding the same prize, so it builds faster, but it does not change the odds of winning for any individual player.

Must-drop jackpots

A must-drop jackpot is designed to pay out by a certain time or once it reaches a certain amount. This affects when it is awarded rather than the underlying randomness of the game itself. The exact condition is set out in the game’s own information, and it is worth reading before assuming what must-drop means.

Where to read the details

The specifics, such as the seed, how contributions work, and how the jackpot is triggered, are set out in each game’s own rules. Reading those is more reliable than the headline figure, and as always it is wiser to treat a jackpot as a remote possibility rather than something to plan around or chase.