Slot Bonus Features Guide
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In this slot bonus features guide, we uncover the most popular features of online slots. This includes a diverse selection of slot machine features such as free spins and multipliers, to more unqiue features such as cascading reels. Continue reading, as we learn more about how video and arcade slots become alive through their exciting bonus features.

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Slot Bonus Features Guide: An Introduction

Online slots are unique in almost all ways, especially down to their special bonus features. Essentially, these are bonus rounds that present the opportunity of winning in more ways than one to players. Bonus rounds increase the chances of winning and make both video and arcade slots all the most enjoyable to play.

In this slot bonus features guide, we delve into the most popular bonus features in online slots. Once you become familiar with them, you can play jackpot slots for yourself, trying to win the biggest prizes in the most thrilling way.

Slot Bonus Feature Explained

Modern slot machines have a huge range of bonus features, and developers are continually innovating and coming up with new ones. Each bonus works in a slightly different way, but the common one include free spins, payout multipliers, and picking games. Very often, a bonus will combine many different features together.

Here we will look at the most common types of bonus features. When you go to play a game, you will be able to find all the details you need about its features in the paytable and by reading through the following, it will give you the basic knowledge needed to understand exactly what is on offer.

Free Spins

Free spins are the most common bonus feature. As the name suggests, they are spins of the slot machine that you can play for free that give you the chance to win real money (as opposed to playing the game for free in demo mode). In many slots, the free spins will begin if you manage to land at least three scatter symbols on the reels simultaneously.

Slot Bonus Features Guide
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For example, landing three scatter could award 10 free spins, four scatters 20 free spins, and five scatters, 50 free spins. However, this is not always the case and there are many other mechanisms that may trigger the spins. In some games, you may be able to win additional free spins after they have begun by landing more scatter symbols.

Very often, the free spins will come with extra bonus features. For instance, in some slots, all winnings may be doubled during free spins or there may be a special symbol that multiplies the payouts (this is explained more below). Other free spins may come with expanding symbols, special symbols, and more. When applicable, you will always be able to find details of these extras in a slot’s paytable.

Payout Multipliers

Payout multipliers do what the name implies, they multiply the payouts. They can appear in many different forms within a game. For example, there may be a symbol that comes with a payout multiplier attached, such as x2 or x3 multiplier. If that symbol then forms part of a winning combination, the payouts will be subject to the multiplier.

As mentioned above, sometimes in a free spins round, all winnings will receive a multiplier. You may also find increasing payout multipliers and these can be implemented in various different ways.

A basic example may be a free spins round of 10 spins in which the first five have a x1 multiplier, the next three have a x2 multiplier and the final two spins have a x5 multiplier. You should make sure that you are aware of any payout multipliers available in a slot as often they are the key to the biggest wins.

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Bonus Picking Games

Picking games have been a very popular bonus feature for decades. As the name suggests, you will be asked to choose from objects to reveal prizes. Most often, the bonus will relate to the game’s theme; for example, in an Ireland themed slot you may be asked to choose from shamrocks or leprechaun’s hats.

Most often, when you trigger a picking game you will be awarded a certain number of picks. Each of these picks will then reveal a guaranteed prize. However, some games may award an unlimited number of picks, and you can continue to choose objects until you find one that ends the game. You won’t necessarily only be revealing cash prizes, you may also find payout multipliers, extra picks, or even trigger additional bonus games. Some picking games have multiple levels with bigger prizes available at each level. While there is some variation in this, it is never complicated and you will find a clear explanation in the slot’s rules.

Stacked, Expanding and Sticky Symbols

These are three types of bonuses that can be applied to any symbol, both in the main game and in free spins. If a symbol is stacked, it means that there will be multiple instances of it on top of each other on a single reel. This way, it becomes easier to fill the reels with the same symbol, which in turn makes it easier to land high value winning combinations.

Slot Bonus Features Guide
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If a symbol can expand, it means that when it lands on the reels it can grow to fill more rows. Most often symbols will expand vertically up and down to fill the entire reel, but there are games with symbols that can expand horizontally across the reels.


In recent years, it has become very common to find a special type of expanding symbol in free spins rounds. Before the spins begin, one of the regular a symbol is chosen at random to become an expanding symbol. Then, whenever it lands on the reels, it will expand to fill the entire reel. Furthermore, when this happens, the symbol will payout as long as there are enough of them along a payline, even if they are not on adjacent reels.

Importantly, this is not quite the same as a scatter symbol. Scatters will payout regardless of where they are on the reels, but with these expanding symbols, they must be along a payline (for example, a symbol on reels one, three and five on the same payline will award a three of a kind payout).

Finally, a sticky symbol is one that remains in a fixed place on the reels for subsequent spins after it has landed. For instance, you may find a free spins game with sticky wilds. In this instance, every time that a wild symbol lands during the free spins it will then remain in that position on the reels. Sometimes the symbol may become sticky for the duration of the free spins round and at other times, it may be for a specified number of spins.

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Tumbling/Cascading/Rolling Reels

This is the same feature that goes by many different names. In its most common form, every time that a winning combination lands on the reels, after the win has been paid, the symbols in the combination are then removed from the reels. This allows more symbols to fall from above, potentially forming another win and allowing the process to repeat itself. This process can continue indefinitely and in many instances, each successive tumble/cascade/roll will increase a payout multiplier that does not reset until a win fails to land.

Occasionally you may find an inverted version of this. In other words, all the symbols other than the winning combination are removed from the reels. More symbols then fall from above and if it improves the existing win or forms another win, then the process repeats itself until no more wins are formed.

Progressive Jackpots

Progressive jackpots are hugely exciting as they can be worth an enormous amount of money. When playing a progressive slot, a portion of each bet is contributed to the jackpot pool. There are two types of jackpot pools, local and network. A local jackpot is specific to the casino you are playing at while a network pool is contributed to from multiple casinos, and these can grow to be worth millions.

There is no fixed way in which a progressive jackpot is won. In some games, you may simply need to land a five of a kind combination of a specific symbol along a payline. Other games may have a special jackpot bonus game that can be triggered at random or through special symbols. There are even games where the jackpot can be awarded entirely at random on any spin.

It is always important to read the rules carefully when playing a jackpot slot, as some of them may have minimum bets required to qualify for the jackpot and there would be nothing more frustrating than landing the winning combination only to discover you were not betting enough to hit the jackpot.  Furthermore, some slots state explicitly that the more you are betting per spin, the better your chances are of winning the jackpot.

Hold and Win Bonuses

This type of bonus game has exploded in popularity over the last couple of years. The bonus looks similar to a free spins round but works completely differently.

Slot Bonus Features Guide
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Usually it takes place on a special set of reels where each position spins independently. There will be just three things that can land in each position, a cash value symbol, a jackpot symbol, or a blank. You begin with three respins with the triggering symbols frozen on the reels. Each time that a cash or jackpot symbol lands, it too is frozen on the reels and the respins counter resets. The spins continue until either each position is filled or the respin counter reaches zero.

At that point, you win the total value of all the cash symbols and potentially a jackpot prize depending on the symbols that have landed. With these bonuses, the jackpot prizes are normally fixed (e.g. 5000 times the total bet). Not every Hold and Win bonus will work in exactly this way, but they are all very similar.

Gamble Features

Some games will give you the chance to gamble your winnings after every winning spin (although, this is illegal in some jurisdictions). Most gamble features simply ask you to guess if the next card drawn from a pack will be red or black. If you guess correctly then your payout is doubled, if you guess incorrectly then you lose all of your winnings.

You can often gamble your winnings many times in a row up to a predetermined gamble limit, and some games will allow you to gamble just half of your winnings so that you don’t risk losing them all. You will also find gamble features that give you the chance to quadrupole your winnings by correctly guessing the suit of the next card to be drawn. While this can be a lot of fun, you should be careful, as there is a very real chance of losing all of your winnings.

The Bottom Line

To conclude this slot bonus features guide, we recommend picking games that use at least one of these bonuses. If you find online slots with more than one of these bonuses, you can rest assured the gameplay is going to be absolutely thrilling. If you are ready to play these games for yourself, head over to our latest jackpot ratings, where you will find plenty of slots featuring the biggest of prizes.

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