Forget paylines. Forget ways-to-win. Cluster pays slots offer a revolutionary way to form those much sought-after winning combos. It does this by clustering symbols together.

The game mechanic that was invented by Netent in 2017 has become something of a staple of the video slots category, thanks also to a number of well-crafted games that have popularised the Cluster Pays system. Think Jammin’ Jars by Push Gaming or Reactoonz by Play'n GO, both smash hits that are still hugely popular.

In this complete guide, I'll take you through everything you need to know about online slots that use the Cluster Pays mechanic and the best casino sites where to play them.

This is a classic case where the name does say it all. Cluster Pays slots are online casino slot games that use a game mechanic that enables clusters of winning symbols to form on the reels - these clusters of matching symbols replace the traditional payline system (where you would need matching symbols along predefined paylines to form a win).

Symbols in a cluster need to touch either horizontally or vertically. The size of the cluster required to trigger a win can vary from one slot to another.

Although this innovative concept was NetEnt’s brainchild, many game developers have since embraced the Cluster Pays mechanic, creating a huge range of Cluster Pays slots with unique themes, features, and gameplay.

As soon as you open a Cluster Pays slot, you will notice something that is very different from other traditional slots – all the action takes place on a grid. This is why this type of games are also called grid slots. They look more like arcade games than slots, in fact. Think Tetris, for example, the cult puzzle video game created in 1985 by Russian Alexey Pajitnov.

Instead of a set of spinning reels with symbols, you get a square grid into which symbols drop. Depending on the game you’re playing, if you manage to land a cluster of 4 or more matching symbols that connect horizontally or vertically, you’ll get a win. Using the cascading or tumbling reels mechanic, the winning symbols disappear, and the ones above them fall down to replace them. This gives you a chance to form consecutive wins from each single spin.

Because there are no fixed paylines here, this game mechanic also gets rid of the traditional left-to-right symbol order of classic slots. Clusters of winning symbols can appear anywhere on the grid, meaning they do not need to begin from the first column.

Special Symbols and Features

You’ll notice that most Cluster Pays slots use special symbols like wilds and scatters that modify the gameplay. Both function like on any other slot, with wilds substituting for other symbols in clusters, while scatters typically trigger bonus features or free spins.

Some grid slots also feature multipliers. Usually, the multiplier increases with each consecutive win.

Where to Play Cluster Pays Slots

I've explained what cluster pays slots are, and I've also given you an overview of how they work. Now it's time for me to talk about where to find them. The only online casinos you should be looking at to play Cluster Pays slots are the licensed and reputable ones I recommend below. Take your pick!

To form winning combos, you will need to land 4 or more matching symbols that touch vertically or horizontally (the minimum number depends on the slot you’re playing). The values of symbols vary, and you can easily check these on the game info page. If the game has special symbols or modifiers, like multipliers, it means that you can win bigger amounts if these come into play.

One of the best features of Cluster Pays slots is the Cascading Reels mechanic. As soon as a winning cluster of symbols is formed, the symbols are removed from the grid, letting the symbols above them replace them. This creates new opportunities to form clusters and a chance to get consecutive wins from just one spin.

Can you determine the outcome of a spin? No. Like every other certified online slot out there, Cluster Pays slots use Random Number Generator (RNG) technology to ensure that wins are completely randomized. The RNG engine inside the code of the Cluster Pays slot generates a random value between 0 and 4 billion in a millisecond - the outcome is impossible to guess which means there is absolutely no strategy that will help you win.

When playing Cluster Pays slots (or any other slot for that matter), I like to set a budget for my gaming session and adhere to it no matter what. I do recommend this, because it will help you keep control over your bankroll. While these slots can be captivating, it's very important to play responsibly to prevent excessive spending.

Cluster Pays Slots Free Play

Some online casinos may offer you the chance to try Cluster Pays slots in demo mode. Playing the slots for free gives you some time to understand how the game works, what the symbols mean and what triggers which feature. Then, when you’re ready to play Cluster Pays slots for real money, you’ll know what to expect.

Here’s my top ten list of Cluster Pays slots, in no particular order:

Not ready for Cluster Pays slots yet? Check out some alternatives:

Megacluster Slots – A Different Type of Cluster Pays Slots

Clusters were not enough for Australian game maker Big Time Gaming. So they invented Megacluster Slots, games with a slot mechanic that can generate a much larger grid and, in turn, more chances to form winning combinations.

The foundation of the Megaclusters mechanic is the same as the Cluster Pays system. The difference is in what happens after a cluster is formed, whereas with the Big Time Gaming mechanic, you’ll see symbols in a winning combination split into four smaller symbols.

The first game to feature the Megaclusters mechanic was Star Clusters, which was released in 2020. It was followed by:

• Millionaire Rush Megaclusters
• Diamond Fruits Megaclusters
• Kluster Krystals Megaclusters
• Cyberslot Megaclusters
• Star Clusters Megaclusters

Classic Slots

3-reel slots, or classic slots, are as traditional and straightforward as you can get. Focusing on simplicity, they feature just a few symbols, like cherries, bars, and lucky sevens, arranged across three reels. You’ll typically have only a handful of paylines, making for uncomplicated gameplay. Try Play’n GO’s Fire Joker for that true classic feeling. 

Megaways Slots

Like Cluster Pays games, Megaways slots brought innovation and a breath of fresh air to the online casino industry. These games feature a dynamic mechanic that gives you a number of different ways to win on every spin. In some games, the ways to win can reach up to hundreds of thousands! If you want a fine example, we suggest you try Big Bass Bonanza Megaways by Pragmatic Play. 

Video Slots

You could technically say that Cluster Pays slots are also video slots, and you wouldn’t be wrong. However, there are so many Cluster Pays slot titles nowadays that they have branched out on their own. Still, video slots offer a vast universe of creativity and entertainment. Immortal games such as Starburst and Book of Dead are an example of what you can expect. Games that look good, play good, have immersive soundtracks, and come in a wide range of themes.

Progressive Jackpot Slots

When you think of ever-increasing prize pools, often reaching astronomical sums, you’ll certainly think of Mega Moolah, Hall of Gods, or Mega Fortune. These are progressive jackpot slots that have turned ordinary players into millionaires overnight.

These are highly volatile games, so do not expect frequent wins as you would on a Cluster Pays slot. But if you manage to hit that pot …

Table Games

Online casinos are not always about reels that spin. Blackjack, roulette, poker, and baccarat are gambling games far older than slots and still retain a lot of interest. Here, some degree of skill can impact the results. Take Blackjack, for instance. It is up to you to beat the dealer by getting a hand value as close to 21 as possible without exceeding it.

Live Casino Games

Many online casinos that offer Cluster Pays slots will also have a section with live tables hosted by real, professional dealers and streamed in real-time to your device.

Among the most popular live games, you’ll find game shows like Dream Catcher, Monopoly Live, and Crazy Time, as well as more traditional games, including live blackjack, roulette, baccarat, and poker.