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A Complete Guide on Slot Bonus Features

Gaming developers are constantly on the hunt for the next big thing in slots and casino game features. Slot bonus features provide punters with new and exciting possibilities of playing their favourite games. Read on to find the best of them in our guide!

Viking Runecraft

Viking Runecraft Logo
 Software: Play’n Go
  •  Return to player (RTP):  96.00%
  •  Volatility:  High
  •  Release date:  2017
  •  Game type:  7x7-reel, 1-line
  •  Features:  Cluster Pays, Free Spins, Replicating Symbols, Cascade Wins

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Viking Runecraft Review

Lava Gold

Lava Gold Logo
 Software: Other
  •  Return to player (RTP):  95.99%
  •  Volatility:  Medium-High
  •  Release date:  2021
  •  Game type:  5x5 reel; Cluster Pays
  •  Features:  Prize meter, free spins, cluster wins, multipliers

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Lava Gold Review


 Software: Yggdrasil Gaming
  •  Return to player (RTP):  94.99%
  •  Volatility:  Medium-High
  •  Release date:  2022
  •  Game type:  5x3-reel, 20-line
  •  Features:  Free spins, multipliers, random cash prizes, retro style

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Achilles - Unavailable

El Paso Gunfight xNudge

 Software: No Limit City
  •  Return to player (RTP):  96.05-96.35%
  •  Volatility:  High
  •  Release date:  2021
  •  Game type:  5-reel
  •  Features:  xNudge Wilds, free spins, Bonus Buy, choice of volatility modes, Jumping Wilds

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El Paso Gunfight xNudge - Unavailable

Longmu and the Dragons

 Software: Other
  •  Return to player (RTP):  95.40%
  •  Volatility:  Medium
  •  Release date:  2021
  •  Game type:  5x3-reel, 50-lines
  •  Features:  Cluster Free Spins, multiplier wheel, cascades, minigame

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Longmu and the Dragons - Unavailable

Jack and the Beanstalk

 Software: NetEnt
  •  Return to player (RTP):  96.28%
  •  Volatility:  High
  •  Release date:  2011
  •  Game type:  5-reel, 20-lines
  •  Features:  Free spins, walking wilds, stacked wilds, expanding wilds

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Jack and the Beanstalk - Unavailable

What is a Slot Bonus Feature?

You’ll find that many top casinos will have tonnes of slots with terrific bonus features in store, allowing you to trigger a prize feature following a regular spin. Bonuses may trigger randomly or may be activated when you land scatter symbols.

Bonus features should activate regularly, so it pays to look around for slots with high hit rates. Average payouts should also be attractive enough to make the spins leading up to a hit worthwhile.

Benefits of Slot Bonuses

An online slots bonus is a great way to enhance your prizes without paying extra. You only pay for playing the base game, after which bonus features are triggered whenever you land special symbols.

What Kind of Features? What Kind of Features?

All the top slots online offer a mix of free spins, respins or prize wheel features. In some games, you can even activate a progressive jackpot which is linked to multiple online casinos.

Where To Find Slots With Bonus Features

Leading slot developers offer a variety of games with lucrative bonuses, all the while offering cutting-edge graphics and animations as you spin the reels!

Let’s face it, you’ll be hard pressed to find a slot without any kind of bonus feature at all – we’re not stuck in the mid-2010s after all. Rest assured that all casinos we recommend here at Top10-CasinoSites will have you covered!

However, it's also important to do your own research as well. We always recommend testing out slots for free if possible (i.e. via the demo version) before going ahead and staking any real money.

Different Kinds of Bonus Features

Below, we've listed some of the most common features slot developers implement to enhance their games.

Free Spins

Free Spins Slot logo

Free spins are an attractive bonus feature popular with most players, and are found in a huge number of slots online.

To trigger them, you'll usually need to land 3 or more “scatter symbols” on the reels. In certain games, you'll also be sometimes granted additional multipliers or enhancements.


A respins bonus is an increasingly common feature in new online slots, usually received after any win or cascade, or by landing scatter symbols.

Some newer slots offer special respins where the spins reset. For example, you may begin with 3 respins, which reset to 3 after each win. Once the respins have run out, so does the bonus feature.


Vikings Go Berzerk Slot

A scatter symbol is simply an icon that pays out a prize wherever it lands on the reels without needing a winning combination. You earn a cash payout for each scatter that appears. The key here is to aim for hitting several scatters at once to get big rewards!


Wild Wild Riches Slot

Most 5-reel slots feature wild symbols, which replace all regular symbols and helps to fill in the gaps on a payline. Some slots pay a jackpot if you land 5 wilds on a payline.

Types of Wilds:

These wilds will stretch to fill the entire reel. This has the potential for increasing the prize payout on that spin.

These are special wilds that appear on top of each other at the same time. You might get a stack of 2 or 3 wilds in one spin.

These symbols remain in place for another spin or for the duration of a bonus round.

This is a feature where a wild symbol appears at one end of the reels and moves along one spin at a time until it disappears from the screen. The wild is active every time it moves.

These are symbols that transform into wilds when they appear on the screen.

This special wild multiplies any payout when it helps to complete a payline. Wild multipliers can double or treble your payout, depending on the game.

These wilds appear in slots that have multiple sets of reels. When one wild appears on a set of reels, it replicates to appear in the same position on all sets of reels.

Nolimit City’s xNudge Wild has a special ability when it appears partially: it nudges up the screen to appear fully on the reels. It’s similar to the Nudge feature that you’ll find in classic slots and fruit machines.


Drive Multiplier Mayhem

Multipliers are special symbols that enhance your payout on a winning spin. Typically, multipliers apply to wilds (jokers that replace other regular symbols). However, multipliers can also appear as dedicated symbols on the reels.

Most of the time, multipliers are applied to free spins bonuses. You may trigger, for example, 10 free spins with a 3x multiplier on every spin.

Some bonus features also give you a choice of multipliers before you play. You may get to choose a free spins amount (e.g. 5–30) and a multiplier to go with the spins (e.g. 3x–20x).


Megaways is an innovative slot mechanic devised by Big Time Gaming (BTG). Here, each reel contains anywhere from 2–7 symbols at a time. The number of paylines therefore changes from one spin to the next. Hit 7 symbols on each reel, and you’re looking at a maximum of 117,649 ways to win on a single spin.

Licensed Megaways Games Licensed Megaways Games

The beauty of Megaways is that multiple slot developers have adopted the mechanic in their games. As well as the original BTG Megaways game, Dragon Born – released back in 2015 – you can load up recent games such as NetEnt’s Gonzo’s Quest Megaways, Red Tiger’s Ali Baba’s Luck Megaways and BTG’s own hit game, Bonanza Megaways.

Each developer adds its own unique twist on the Megaways mechanic, adding additional features such as Falling Wilds, respins, and prize multipliers.

Megaclusters works a little differently. The mechanic was unveiled in 2020 with the release of BTG’s Star Clusters game. You win a cash prize by matching symbols horizontally or vertically. At the same time, matching symbols split into four smaller symbols which in turn offer the opportunity for bigger wins.

You can discover the very best Megaways and Megaclusters slots with our exclusive round-up. We’ll show you in a little more detail how you can make the most from BTG’s amazing bonus features.

Cluster Pays

Cluster Pays, or Cluster Win, slots were popularised following successful apps such as Candy Crush. Instead of traditional paylines triggering payouts, you win a prize by matching groups of symbols in adjoining spaces. Matching “clusters” can run horizontally or vertically but normally must consist of at least 5 symbols to pay.

In addition, winning clusters then disappear after a spin, leaving the symbols above to drop into their place. This can create even more payouts, triggered totally for free!

NetEnt casino games are some of the most beloved in the industry. The developer has produced several Cluster Pays games. Games such as Aloha! Cluster Pays and Shangri-La offer stacked symbols which combine to produce big payouts. You can also trigger a free spins bonus in both games.

If you want great Cluster Pays slots with bonus features, check out some of Pragmatic Play’s games. Sweet Bonanza is probably the closest game you’ll get to a classic mobile app such as Candy Crush. The 6 reels are filled with sweets which award prizes whenever you match 5+ in any direction.

Prize Wheel

The prize wheel evokes classic slots from Las Vegas, such as IGT’s Wheel of Fortune. In a land-based slot machine, the prize wheel is often represented by a physical wheel that spins during a bonus game. However, in online slots, the wheel is animated and governed by a random number generator (RNG).

Prize wheels are usually triggered at random, either after a single spin or by triggering a bonus. The wheel features segments containing cash amounts, multipliers, or free spins. There may also be a jackpot displayed on some of the wheel sections.

Some progressive jackpot slots, such as Microgaming’s Mega Moolah, use a prize wheel to determine their biggest prizes. When you trigger the special feature, you must spin the wheel and line up the arrows in order to unlock the huge progressive jackpots offered.

Instant Win/Click to Win

The Instant Win feature offers you the chance to win extra cash without leaving your regular game. The Instant Win can be triggered at random after any regular spin. Special reel positions are highlighted, and you must select from the hidden icons on the screen. You’ll reveal a cash prize which is immediately added to your bankroll.

Gamble Feature

Gladiator Slot

Lots of classic slots and early 5-reel slots offer a gamble feature. Here, you have the chance to double your win by playing a small bonus game.

First, you are offered two choices: collect your payout or select the gamble feature. Classic gamble features include a Red/Black game where you must correctly guess the colour of the next card drawn. Alternatively, you may play a Hi-Lo number-guessing game or a prize ladder with some skill element: stop the flashing light on the right ladder step to increase your payout.

Pick’Em Bonus

The Pick’em Bonus has been a popular feature in slots for years. You activate the game by landing scatter symbols on the reels. You are then presented with 10–20 secret symbols from which you must pick a handful to reveal cash prizes or free spins.

Win Both Ways Paylines

Yokozuna Clash Slot

Win Both Ways is a fun take on the traditional paylines found in many slots with bonus features. In regular online slots, paylines generally run left to right. You must line up matching symbols starting at reel 1.

In Win Both Ways slots, however, paylines run both left-to-right and right-to-left. For instance, a 20-payline Win Both Ways slot may offer 10 paylines going left-to-right and 10 running from the right.

How to Trigger Slot Bonuses

In most slots, bonus features are triggered by hitting scatter symbols. Typically, you must land 3 scatters in any position on the screen – they don’t have to form part of a winning payline. Some slots bonuses trigger if you land scatters on specific reels, such as anywhere on reels 1, 3 and 5.

Some slots offer a ‘second chance’ if you only land 2 scatters. You may get to spin another reel in order to land that elusive third scatter and trigger the bonus.

Finally, some of these features simply trigger at random. You won’t know when the bonus is going to activate, but the decision is governed by the game’s random number generator (RNG). RNGs are regularly checked for fairness as long as the developer is licensed and reputable.

The Bonus Buy Feature

Why wait when you can skip straight to the action? That’s where a Bonus Buy feature comes in.

With the Bonus Buy, you can pay a set stake and immediately trigger the slot’s main bonus game. The price for activating the feature is clearly displayed on the screen. Simply pay your stake and play the bonus. However, be aware that the Bonus Buy isn’t readily available at UK-facing casinos.

Finding Out if a Slot Game Has Bonus Features

To find out what a slot has to offer, open the ‘Instructions’ or ‘Paytable’ tab to bring up details on the game.

The paytable usually lists every bonus feature in the slot and how you can trigger it. You’ll also see a list of payouts, jackpot prizes, and other information such as RTP.

What To Look Out for When Choosing a Slot Game

It’s important to choose the right games if you’re hunting out slots. Here are some of the criteria we recommend looking for.

What you need to look out for:

Whether you’re into online casino games or slots, it’s important that you enjoy the game. There’s nothing worse than getting bored while playing bonus slots, especially if you spend a lot of money or time trying to activate a feature.

Some slots with features only contain one or two special bonus features. In isolation, it’s fine to have just wilds and a free spins bonus. However, always check the paytables to ensure the top jackpots are worth your playtime.

It can be easier to trigger a bonus feature if the slot has a lot of ways to win. The fewer the paylines, the harder it can be to activate the main bonus. However, a lot of ways to win can also be expensive. It’s important to find a good balance between the number of paylines and how generous the bonus features are.

The biggest slot bonus is the progressive jackpot. Jackpot slots differ in the way they pay out their top prizes. Some games trigger the progressive at random, while others pay out once you’ve successfully navigated a bonus game.

Some progressive slots are more popular than others. The more popular the game, the more money is poured into the jackpot and the higher it becomes. This is an important factor if you’re on the hunt for the biggest prizes.

Every online slot has its own RTP. This is the average payout made to players over the long term. You can usually find the RTP in the paytable, and it gives a good indication of how much is paid back to players over millions of spins.

Volatility is a good indicator of how often a slot pays out. A high-volatility slot will feature a lot of bonuses but won’t pay out very often. A low-volatility slot will pay plenty of smaller cash prizes.

You can sometimes find the slot’s volatility rating in the paytable. Try to look for medium-to-high volatility games to get the best bang for your buck.

Many online casinos offer bonuses and promotions which reward you when you play slots. You can opt in to the top casino bonuses and play your favourite slots in order to win free cash and bankroll your next gaming session!

Top Slot Games With Bonus Features

Not sure where to start? We've compiled a list of our favourite games below to help you out.

Viking Runecraft – Play’n GO

Few Norse-themed slots offer progressive bonus structures like Play’n GO’s Viking Runecraft. You can win up to 5,000x your stake as you climb the levels and try to reach Valhalla.

Viking Runecraft utilises a Cluster Pays mechanic where you win cash by matching groups of runes on the screen. Winning clusters disappear and trigger a free respin too.

In addition, you climb a prize level by clearing a set pattern of symbols on the reels. As you progress, you earn special modifiers based on the Norse gods. For example, Thor will strike lightning on the reels and add wilds. Odin, meanwhile, creates groups of wilds that can enhance your payouts.

While the RTP of Viking Runecraft is only 96.00%, the range of bonuses makes the slot worth playing.

Lava Gold – Betsoft

Lava Gold is an atmospheric slot from BetSoft set in a prehistoric jungle. As you land clusters of matching dinosaur symbols, you’ll fill a special prize meter alongside the reels.

You trigger a free spins bonus when the lava meter is full. In addition, you can land volcano wilds which substitute for all other symbols. Best of all, the free spins begin with a 1x multiplier on wins. The multiplier increases by 1 for every extra win, which means you could hit a 10x multiplier on your final free spin.

Cluster Pays slots are popular in 2022 as the quality of the software improves. You can win a special jackpot if you hit a cluster of 25 matching icons across the reels.

With all of this together with an RTP nudging 96%, what’s not to like about Lava Gold?

Achilles – Yggdrasil

Yggdrasil’s 2022 release, Achilles, is a fun take on the legend of the Trojan War. The 5-reel slot features various modifiers based on icons from the story, such as Agamemnon, Achilles, and the Trojan Horse.

Features include free spins with sticky wilds and the Skinny Greek Soldier Modifier, where rocks are fired across the reels to leave random mystery symbols.

The RTP of 94.99% is a little lower than other Yggdrasil slots, but the breadth of bonus features makes Achilles worth playing.

El Paso Gunfight xNudge – Nolimit City

Nolimit City have pioneered online slots over recent years with the best casino bonus games. El Paso Gunfight xNudge uses one of Nolimit City’s most popular bonus features.

In the Wild West-themed slot, you get to choose a reel setup. The Deputy Badge or Marshal Badge can appear on the reels, determining the volatility of the gameplay.

In addition, the slot features xNudge Wilds. These are 3-high wilds that replace all regular symbols. However, if the wild isn’t fully in view, it can nudge higher up to fill the reel.

El Paso Gunfight xNudge also includes a free spins bonus round. During the feature, Jumping Wilds can appear and will move into new reel positions on every spin.

Longmu and the Dragons – Red Rake Gaming

Longmu and the Dragons is an Oriental-themed slot by Red Rake Gaming that incorporates Cluster Wins with free spins and some amazing graphics.

You can trigger the Moons of Fortune minigame by landing 3+ scatters on different reels. You win 3–5 free spins with special cash prizes awarded depending on what’s displayed on the screen.

In addition, you can enhance your mini-game wins by spinning the Multiplier Wheel. Your prize is multiplied by 2x to 10x, depending on where the wheel stops.

Longmu and the Dragons also features a separate free spins bonus. Whenever you hit 5+ winning cascades during the base game, you trigger the free spins. It’s possible to trigger up to 30 free spins.

Jack and the Beanstalk – NetEnt

Jack and the Beanstalk is one of NetEnt’s most popular slots, offering some of the best bonus features around. You can trigger free spins, and there’s even a jackpot worth 600,000 coins. The game also introduced slots players to the Walking Wild feature.

The free spins bonus is pretty standard, but the Treasure Collection feature makes the game special. During the game, you collect special symbols which earn you special modifiers such as stacked wilds and expanding wilds.

When a wild appears on the reels, you earn a re-spin. During this spin, the wild shifts along one reel to the left. You then re-spin, and the wild keeps moving until it disappears from the reels. Plus, you win a 3x multiplier on any winning payline the wild helps to complete.

Game Providers

So, who are the brains behind all these fantastic bonus features? To find out, check out our below compilation of the most renowned providers in the industry, whose games can be also found at premier cryptocoin casinos or GBP-accepting gambling sites.

Top Providers:

Yggdrasil have built up a solid collection of online slots under their own name and in partnership with smaller studios. They have pioneered mechanics such as Gigablox and Splitz while providing a Buy Bonus option to all eligible players.

Microgaming was one of the earliest providers to use scatters and wilds in their slots, in games such as Thunderstruck and Break Da Bank Again. Also look out for the Pick’Em Bonus in slots such as Bridesmaids.

Scandinavian slots developer, Play’n GO, have been producing bonus slots since the 1990s. They pioneered the Cluster Pays mechanic in slots such as Sweet Alchemy and Reactoonz. More recently, Play’n GO introduced huge paying symbols in games like Gigantoonz to give the Cluster Pays slot a 2022 facelift.

NetEnt are a leading developer of casino software, including the best online slot bonus games, roulette, and live casino games. They have pioneered some of the biggest online slots bonus features, such as cascading reels and walking wilds. Games like Gonzo’s Quest and Jack and the Beanstalk are still hugely popular with casino players.

Big Time Gaming (BTG) are the brains behind the Megaways and Megaclusters mechanics. While BTG licence out their Megaways mechanics to other providers, they still produce some of their own games like the excellent Bonanza Megaways.

How Do You Know if a Slot Game Is Legit?

There is an easy way to know if a slot is above board. Legit slots are designed by online casino providers who have the required online gambling licences. Gaming licences are issued by approved bodies such as Malta Gaming Authority. In addition, legit games are only supplied at online casinos that also have the proper licences in place.

Games must also be tested and are regularly audited by established labs such as eCOGRA. Testing labs perform regular checks on a game’s random number generator and authenticate average RTPs (Return to Player Percentages).

Slot Bonus Features Summary

With continuous advancements in casino software, there has never been a more exciting time to try out different games online! Pick one of our recommendations above to experience the thrill of playing for free or real money with a variety of features, including free spins, wilds, and Megaways.

Slot Bonus Features FAQs

An online slots bonus is a special in-game feature where you can win extra money or a jackpot. You’ll find a list of bonus features and payouts in the slot’s paytable.

You can trigger the best slot bonus features multiple times as long as you pay the correct stake. Some slots also offer a Bonus Buy feature where you can trigger the bonus automatically.

Absolutely. Most online slots are available in Demo Play mode without the need to pay. Simply log in to your casino account and choose the Freeplay mode in the slots lobby.

Yes! You can choose from thousands of mobile slots to play for free or real money on your Apple or Android smartphone. Check out our top-rated mobile casinos here.

Legal slots are developed by licensed casino game developers. In addition, only legit slots are offered at regulated online casinos.

The RTP is the Return to Player percentage. It’s the theoretical payout made to all players over millions of slot spins.

The best providers offer a range of games with smooth graphics and interesting online slots bonus features. Slots must be governed by a random number generator.

Reputable online casinos only supply slots that are independently tested for fairness. RNGs are regularly audited to ensure that every spin is fair and reliable.

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Jake Schembri

Jake Schembri

Author Expert

With well over a decade’s worth of writing experience under his belt, Jake has created content for some of the most prominent casino operators in the industry, most notably Betsson and Betsafe. He enjoys getting into the nitty-gritty of what an operator is all about, leaving no stone unturned when it comes to providing candid, comprehensive, and objective insights.


ticksEditor since: 2023
ticksTotal posts: 240
ticksLanguages: English and Maltese


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