Cluster pays
Cluster pays is a slot win system in which a payout is triggered by a group of identical symbols touching one another horizontally or vertically anywhere on the grid, rather than by symbols lined up along a payline. Each game sets its own minimum group size, most often five symbols, and the paytable pays more as the cluster grows. The mechanic usually runs on a larger square grid, such as seven by seven, instead of the familiar five reels and three rows.
How a cluster is counted on the grid
After every spin, the game scans the whole grid for groups of the same symbol that share an edge. Two symbols belong to one cluster when one sits directly beside, above or below the other, and a corner-to-corner touch does not count on most titles.
Take a game with a five-symbol minimum. Six red gems linked edge to edge form a single six-symbol cluster, paid at the six-gem value in the paytable, while four blue gems sitting in a tidy square elsewhere pay nothing at all.
Shape is irrelevant.
On most cluster games the winning symbols then vanish and new ones drop in from above, which can build a fresh cluster on the same paid spin. That chain is usually called a cascade or tumble, and it is a separate feature that happens to sit alongside cluster pays in many titles rather than part of the definition itself. A few designs also change the neighbour rule, for instance hexagonal grids where each cell has six neighbours, so the help screen of the specific game is the only reliable statement of what counts as touching.
Minimum cluster size in known slots
The minimum is the number that moves most between games, so the table sets out a handful of titles with the grid and threshold given in studio pages and published game coverage. The in-game paytable remains the copy that counts for any version you load.
| Slot and studio | Grid | Minimum cluster |
|---|---|---|
| Reactoonz, Play'n GO | 7x7 | 5 symbols |
| Jammin' Jars, Push Gaming | 8x8 | 5 symbols |
| Sugar Rush, Pragmatic Play | 7x7 | 5 symbols |
| Aloha! Cluster Pays, NetEnt | 6x5 | 9 symbols, per coverage |
Cluster pays versus scatter pays
The term most often confused with cluster pays is scatter pays, sometimes sold as pay anywhere. In a scatter pays game such as Sweet Bonanza, eight or more matching symbols win wherever they land on the grid, whether or not they touch.
Cluster pays demands contact, and that is the whole difference.
Some casino pages and comparison sites still list Sweet Bonanza and similar titles under cluster pays, which is wrong by the rules those games publish. When a lobby filter or a promotion says cluster slots, it is worth opening the paytable, because a free spins offer tied to a named category can include games that use either system. Paylines are the other point of comparison: a line game pays fixed paths starting from the left-hand reel, while a cluster game reads the grid as a whole.
Cluster pays, RTP and hit frequency
Cluster pays describes how a win is recognised, not how much a game returns. RTP is still set by the studio’s maths model, and many studios release the same title in several RTP versions, so the figure on one casino’s info screen may differ from another’s for an identical-looking game.
The minimum cluster size does shape how often the base game pays. A nine-symbol threshold on a 6×5 grid is harder to meet than five on a 7×7 board, which is one reason published coverage describes Aloha! Cluster Pays as a low-volatility title with a modest ceiling, while NetEnt’s own page lists a hit frequency of 21%. That figure is a long-run share of spins across millions of rounds, not a promise that one spin in five will pay during any single evening.
A cascade of clusters also does not make the next spin more likely to land one. Each spin is drawn independently by the RNG, and a grid that has gone quiet is never due a large cluster.
