Online Slot Bonus Features Explained

Online slot bonus features are one of the key factors players consider when deciding which games to play. This is because they add tremendous value to your online casino experience.

From free spins to multipliers via mini-games, jackpots and cash drops, online slot bonus features take the fun and excitement – and big win potential – of the base game to the next level.

Some slots will have just one or two bonus features, while others will be packed full of them.

The way in which bonus features are unlocked differs from game to game, and some even allow you to buy the bonus feature instead of waiting for it to trigger.

Below, we take a closer look at the different online slot bonus features, how they are triggered, the impact they have on the player experience and which slots offer the best bonus features.


Online slot developers are constantly coming up with innovative and exciting bonus features, but these are the most common:


As the name suggests, multipliers increase your winnings by a predetermined amount. This could be anything from x2 to more than x1,000 in some slot games.

While some slots offer multipliers in the base game, most multipliers are attached to free spin bonus rounds. Any free spin winnings are multiplied by the multiplier level achieved during the game.

In some cases, multipliers may be applied to your original bet and not your winnings. This means you will receive your stake, multiplied by the multiplier amount achieved, back as winnings.

Free Spins:

Free spins are the most common online slot bonus feature. In fact, there aren’t many slot games that don’t offer free spin bonus rounds.

Once triggered, you will receive a set number of free spins – these are spins that do not use your wagering balance. The number of free spins you receive will vary from game to game.

Free spins are usually combined with other bonus features, such as multipliers and wilds, and can lead to big, mega and even epic wins.

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Jackpots are one of the most popular online slot bonus features among players, giving you the chance to win life-changing prizes from relatively low stakes.

There are different types of jackpots, from progressives to networks via “must drop” jackpots from Red Tiger Gaming which pay out before a predetermined time each day.

In some slots, jackpots will be combined with a bonus game that you must progress through in order to unlock the main prize.

Mini Games:

Some online slot developers have looked to the world of video and mobile games when it comes to developing bonus features and have created exciting mini-games to keep you entertained.

This includes games that require players to complete a puzzle, navigate a maze, win a penalty shootout, find hidden treasure and more. If you complete the game, you win a prize.

One of the most common mini-games is the “Deal or No Deal” pick-a-box format. Players are given a number of “picks” to unlock various prizes – some of which are better and bigger than others.

Money Wheels:

Money wheels give you the chance to spin and win a range of rewards including free spins, multipliers, jackpots and even big cash prizes.

Once triggered, you will be given a set number of spins on the wheel. Once the wheel is in motion, where the pointer stops will determine the prize you win.

Cash Drops:

Cash drops, as you might expect, are cash prizes that land on the reels. They are not one of the most common online slot bonus features, but they are one of the best.

The value of the cash drop will differ from slot to slot and can sometimes be based on your original bet amount, but they can deliver a substantial win


The way in which you trigger online slot bonus features will vary from game to game but in most cases, they are unlocked by scatter symbols or bonus symbols landing on the reels.

The standard bonus feature trigger is three scatter symbols landing on the reels. With some slots, the scatters can appear anywhere on the reels but in others they must appear on specific reels.

For example, the scatter symbols might have to land on reel one, three and five in order for the bonus feature to be unlocked.

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Scatter symbols trigger the bonus round in Plank Gaming’s Neptune Rising slot

Bonus symbols are another way of unlocking an online slot’s extra features. For example, if the game has a money wheel feature, three money wheel bonus symbols must land to activate it.

The good news for players is that not all online slot bonus features are triggered by symbols landing on the reels – some are activated completely at random.

The video below shows the bonus game being triggered in Plank Gaming’s Puffer Goes Wild slot.


Such is the popularity of bonus features in online slots, some developers have launched games that allow you to buy the bonus feature instead of waiting for it to be triggered in the base game.

Big Time Gaming was the first developer to do this with its White Rabbit title, but now the likes of Blueprint Gaming, Yggdrasil Gaming and Scientific Games also offer it.

The cost of buying the bonus feature is usually your stake multiplied by a predetermined amount, but note this multiplier is often quite high. The cost comes out of your wagering balance.


Online slot bonus features provide significant added value to players, ramping up excitement, anticipation and big win potential. So why do developers include these features in their games?

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Liam Mulvaney, CEO of Plank Gaming

"In most cases it is to offer differentiation within the game.

If a game just offers players a standard spin repeatedly without the possibility of achieving something bigger, the game would become very boring very quickly.

Providing bonus features allows us to add something new, innovative and exciting to the game. It also gives something for players to anticipate – especially when it comes to big wins.”


Who Wants To Be A Millionaire
(Big Time Gaming)

Enter the hot seat and choose whether to gamble your free spins for more – there are 50 up for grabs – or walk away with the free spins you already have.

Play at Party Casino

Wheel of Fortune: On Tour

Fill the petrol tank and progress along the map to unlock a range of bonus features including wilds, free spins, multipliers and a pick-to-win mini-game.

Play at Mr Green

Vikings Go Berzerk
(Yggdrasil Gaming)

There are four Vikings whose “Rage Meters” increase throughout the game. Once one of their meters is full, free spins are activated and that Viking will enter “Berzerk Mode” and become a sticky wild.

Play at PartyCasino

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