Progressive slots: how jackpot meters work

A progressive slot is a slot machine whose top prize grows over time. A small share of each wager is added to a jackpot meter until someone wins it, and then the meter resets to a starting amount, called the seed. This page explains how they work; it is not a recommendation to play.

Types of progressives

• Standalone: one machine with its own meter.
• Local or in-house: a bank of machines in one casino sharing a meter.
• Wide-area: machines in many locations, or many online sites, linked to one large meter.

What the meter does and does not mean

The jackpot contribution is part of the game's theoretical return-to-player (RTP), not an extra on top of it. Every spin is random and independent, so a large meter does not mean a jackpot is "due." The top prize on a large linked progressive is typically very unlikely on any single spin. On some games, only a maximum bet or a side wager makes a spin eligible for the progressive; that rule appears in the game's help or paytable screen.

For RTP, volatility, and the general math of slots, see our slot machine guide.

Play safely, or not at all

This guide is educational. We do not offer games, accept bets, or link to casinos. In the U.S. states that currently license online casinos, you must be at least 21 and physically located in that state. Every casino game on this page has a built-in house advantage or a fee, so treat any money you play with as money you may lose. Set a budget and a time limit before you start. If gambling is causing harm, call or text the National Problem Gambling Helpline at 1-800-MY-RESET (1-800-697-3738) or see our responsible gambling help page.

Sources

• UK Gambling Commission, RTS 9: Progressive jackpot systems (example of regulator disclosure rules)

See also: all game guides, where online casinos are legal, and responsible gambling help.