The Top 10 Slots With Bonus Games & Features Online 2021

Everyone enjoys a good slot game, but a bonus feature can make that game even more exciting. Slots with bonus games are so beloved, as they can provide unique gameplay elements and significant rewards to make the game truly stand out. Here are the top-rated slot machines with bonus games available online for UK players.

Online Slot Slot Rating Best Bonus Bonus Rounds Bonus Features Available At Bonus Terms
5/5 Golden Pot 4 Free Spins World, Dragon Destroy, etc. Grand Ivy Full T&Cs apply. *18+. New players only. One bonus offer per player. Minimum deposit £20. Max bonus bet is £5. Bonus spins on selected games only and must be used within 72 hours. Bonus funds must be used within 30 days otherwise any unused bonus shall be removed. Bonus funds are 100% match up to £300 on your 1st deposit, 25% match up to £800 on your 2nd deposit, and 50% match up to £400 on your 3rd deposit. Bonus funds are separate to Cash funds, and are subject to 35x wagering the total bonus & cash. Only bonus funds contribute towards any wagering requirements. Terms apply. BeGambleAware.org.
4.9/5 Up to £120,000 8 Lake of Legend, Misty Vale, etc. LeoVegas Full T&Cs apply. Free spins - no deposit required & new players only. Claim within 3 days of registration & 3 day expiry. Free spins worth £0.10 each on Book of Dead, winnings paid as cash. Deposit offers available across any two deposits. Both expire 7 days after registration & have 7 days to wager once claimed. Deposit £10, £25 or £50+ & wager 35x for a cash reward. Only cash stakes qualify & wagering contributions vary. 5 free spins on Book of Dead with each qualifying deposit, 3 day expiry. BeGambleAware.org
4.8/5 Sarah Spins 2 Chamber of Spins, Wild Desire Betway Full T&C apply. New customers only. Opt-in required. 100% Match Bonus up to £50 on 1st deposit of £10+. 50x bonus wagering applies as do weighting requirements. Debit Card & PayPal deposits only. Irregular gameplay may invalidate your bonus. This offer is valid for 7 days from your new account being registered. Full Terms apply. 18+. BeGambleAware.org. Bet The Responsible Way.
4.7/5 Up to £121,000 2 Free Spins, Gamble Ladbrokes Full T&Cs apply. *18+. New players only. Min bet £10 on qualifying games. 40x wager reqs (bonus only) on selected games. Bonus valid for 30 days. Certain deposit types excluded. Bets covering >70% of Roulette table excluded. T&Cs Apply
4.6/5 Expanding Wilds 2 Expanding Wilds, Both Ways Pay 888 Casino Full T&Cs apply. *New players only • £20 min deposit • 100% up to £100 Bonus + £30 extra bonus • Bonus wins are capped at £500 • To withdraw bonus & related wins, wager 30 x (bonus amount) within 90 days • Wagering req. vary by game • This offer may not be combined with any other offer • Deposit balance is available for withdrawal at any time
4.5/5 Owl Bonus 2 Free Games, Owl Bonus William Hill Full T&Cs apply. *Opt-in required. New customers to Casino page only. Min Buy in £10. Bonus value 100% of Buy in. 50 free spins with 35x wagering awarded after completing buy-in bonus. Max Bonus £300. 40x wagering. Max redeemable £4,000. Bonus expires after 7 days. Stake contributions, country, currency, game restrictions, and terms apply.
4.4/5 Free Spins Race 3 Free Spins Race, Magic Seven Bonus Mansion Casino Full T&Cs apply. *New customers only. Min deposit £20 max bonus amount £500. First deposit: 100% up to £200. Second deposit: 50% up to £300. Wagering 40x for each bonus. Game weighting applies. Cashback: 5% cashback on first and all other deposits during week 1, 10% cashback on all additional deposits taking place in week 2 only. Bonus betting limits: slots - $/£/€5 all other games – 10% of bonus amount
4.3/5 1000x Your Stake 2 Free Spins, Sticky Wins Playzee Full T&Cs apply. 18+. New players only. Valid for 15 days after 1st deposit. Min Deposit £20 Max Bonus Bet £5 Winnings from spins capped at £50 First 100 Zee spins: 10/day. Spins must be used within 24 hours, Funds within 30 days. Bonus funds are separate to Cash funds, and are subject to 35 wagering (bonus + cash). Game weighting restrictions apply. 18+. Full terms apply. BeGambleAware.org
4.2/5 2500x Your Stake 2 Free Spins, Sticky Wilds BetVictor Full T&Cs apply. *New Customers only. Deposit and wager £10 within 7 days of opening new account. Receive £50 bonus = 1x £20 bonus, 3x £10 bonuses for selected games. Up to 60x wagering applicable. Bonuses expire 3 days after crediting. Credit/Debit card deposits only. Geographical Restrictions and T&Cs Apply, see below. Please Gamble Responsibly.
4.1/5 Up to 20 3 Free Spins, Wilds, Avalanche PlayOJO Full T&Cs apply. *First deposit only. 50 Free Spins on the Book of Dead slot. Min deposit £10. Excl. new players in N.I. Each Free Spin valued at 10p. OJO’s Rewards and Game Play policy applies.

This guide will go over all the important details of the slot machines with bonus games. You will learn how to trigger each feature and how to play it properly. Getting to these bonuses is sometimes difficult, but the great rewards and fun gameplay make it well worth the trouble. Most casinos offer such games, so they aren’t difficult to find, but our guide will show you the best slot sites to win at the following incredible titles.

List of the Top 10 Slot Machines With Bonus Games

Finn and the Swirly Spin (Free Spins World) – From NetEnt

The Bonus Game of the Finn and the Swirly Spin Enter a magical world and draw upon the luck of the Irish with Finn and the Swirly Spin. It is on the top of our list for a good reason, as the game is brimming with unique features and fun gameplay. The game also has low volatility, so you’ll get to enjoy its bonus features frequently and can relax with the soothing soundtrack.

NetEnt have outdone themselves by providing fantastic bonus features, such as the innovative swirly reel. Symbols move in a swirly pattern towards the centre, creating wilds whenever they match. If you can get the special key symbol to the end, you can enter a magical world of free spins. Collect more keys to unlock better bonuses and win up to 500x your stake.

Aside from the free spins, you can encounter bonus features during regular play too. For example, Magic Transform turns regular symbols into higher-value ones. This game is among the top slots games with bonus rounds.

Avalon 2 (Holy Grail Bonus) – From Microgaming

The Bonus Round of the Avalon 2 Join King Arthur on his legendary quest to find the Holy Grail in the Avalon 2 slot game. This incredible sequel game features 243 ways to win and an abundance of bonus features. The core gameplay is standard, with five reels and three rows, but it has some of the best slot bonus games.

Getting three Holy Grail scatters will trigger the Holy Grail bonus and send you on a quest with eight different games. Each game has different gameplay, from rolling dice in Lake of Legends to fighting the Black Knight at the Hall of Shadows. Every time you land the three scatters, you advance to a new level until you reach the Isle of Avalon for a Wheel of Fortune game and a reward of up to £120,000.

During regular gameplay, you can rely on Merlin to work his magic and randomly give you a reward if you didn’t win or multiply your existing prize. Enjoy stunning animations with one of the best bonus game slots.

Immortal Romance (Chamber of Spins) – From Microgaming

The Bonus Feature of the Immortal Romance Uncover the dark mysteries of the vampires in the Immortal Romance slot. Much like a vampire, it might appear to be a normal slot with 243 ways to win, but those who unlock the Chamber of Spins will find a rewarding secret. Wild Desire can randomly fill up to five reels with wild symbols for huge wins during normal gameplay.

Getting three or more scatter symbols unlocks the Chamber of Spins, which can be retriggered as you play it. Much like Microgaming’s Avalon 2, the more times you trigger the bonus, the better your prize. Each of the four characters has different abilities, such as rolling reels or multipliers to win up to 12,000x your stake.

What makes this game popular among bonus feature slots is its storyline. As you play, you’ll encounter beautiful animations telling an engaging and intricate storyline about each character. Combined with the stunning vocal soundtrack, you will find a truly unforgettable experience with the best slot bonus games.

Game of Thrones (Free Spins) – From Microgaming

The Bonus Game of the Game of Thrones Slot Machine Choose your allies carefully and win up to £121,000 with the wonderful Game of Thrones slot. Microgaming brings yet another game to the list of top video slots with bonus games. Enjoy the stylish theme of this 243-ways to win slot from the house banner symbols to the glorious theme song.

The Iron Throne is your scatter symbol, and landing three of it triggers the free spins selection. You then choose a house, each with its own bonuses. For example, Stark has 14 free spins, a 3x multiplier and five stacks of Stark symbols. Use the bonuses to lead your horse to victory and claim the throne. These free spins can be retriggered with three scatters.

For more thrills, you can try the Gamble feature. Bet on a coin flip and win extra rewards if you guess right. There are four stages, each bringing bigger rewards. These features help the game become one of the best slots with bonus games.

Starburst (Starburst Wilds) – From NetEnt

The Bonus Round of the Starburst Slot Machine Enjoy the colourful symbols and big prizes in Netent’s Starburst slot. This low volatility slot has only one bonus feature, but the small and frequent rewards make it extremely useful. With ten paylines and a great techno soundtrack, you can expect one of the best experiences from slot machines with bonus games.

Starburst Wilds triggers whenever a wild symbol lands on reels 2, 3 or 4. It will then cover the entire reel and create winning combinations. After that, the reels will re-spin once with the wilds locked in place for a chance at more prizes. This feature can net you a reward of up to 500x your stake.

Another helpful feature is the “both ways” mechanic. This mechanic means that winning combinations are counted not just from left to right but from right to left as well, so you will have twice the chance to win. This game is one of the bonus game slots that is best suited for beginner or low-rollers.

Merlin’s Millions (Owl Bonus) – From NextGen

The Bonus Feature of the Merlin's Millions Slot Machine

Help Merlin research new spells and earn prizes in the great Merlin’s Millions slot. It has five reels and 50 paylines, and you can expect some big wins, even for slot machines games with bonus rounds with the Superbet feature. This feature allows you to add a multiplier to the wild symbols for bigger rewards.

NextGen has created two of the best slot bonus games. The first appears when you get three orb scatters. These orbs activate five free spins, where Merlin can randomly turn entire reels into stacks of wilds. Gathering three Owl Scatters will instead fill the reels with owl symbols. You can collect rewards until the “COLLECT” symbol appears.

Merlin’s book can get you up to 1000x your stake for a truly astounding reward. The great sound effects and fluid animations add a fun character to this game, making it incredibly satisfying when you win. Whether you’re a high or low roller, this game is enjoyable for everyone.

Frankie Dettori’s Magic Seven (Magic Seven Bonus) – From Playtech

The Bonus Game of the Frankie Dettori's Magic Seven

Relive the excitement of Ascot 1996 with the incredible Frankie Dettori’s Magic Seven slot. With 25 paylines and a maximum payout of 194.425x your stake, this is an outstanding game among video slots with bonus rounds.

You can find two fantastic bonuses when you play this game developed by Playtech. The first appears when you land three scatter symbols of the logo. You then pick a horse and win up to 35 free spins if your choice wins the race. The second feature is the Magic Seven Bonus. Landing two ‘BONUS’ scatters will bring you to a racetrack where you pick tiles and reveal rewards. This game continues until you get the ‘Collect’ symbol.

What makes Frankie Dettori’s Magic Seven stand out from other bonus feature slots is the wonderful theme. During bonus rounds, you will be able to see clips from Frankie’s race at Ascot, and the upbeat music will help you feel like a real winner. Have fun with this thrilling race.

Jack Hammer (Sticky Wins) – From NetEnt

The Bonus Game of the Jack Hammer Online Slot

Help the colourful detective stop the mad scientist in Jack Hammer. This 25 payline slot has a unique comic book style and atmospheric sounds, creating an immersive game among other slots with bonus rounds.

NetEnt is known for its excellent bonus game slots, and this one has two exciting features. Getting five or more free spins symbols can get you up to 30 free spins. Alternatively, every time you score a win, the reels will re-spin for a chance at more prizes, with the winning combination sticking in place. This feature continues until you stop landing wins. You can win up to 1000x your stake with five detective symbols.

As this slot’s volatility is low, you can expect to win small but frequent prizes. The low volatility also means you will encounter the bonus games more frequently, so even low rollers can enjoy them. Experience fun mechanics and a great story, with this fun and casual slot suitable for everyone.

Dead or Alive (Sticky Wilds) – From NetEnt

The Bonus Game of the Dead or Alive Slot

Journey to the wild west with the marvellous Dead or Alive slot. This is one of the more difficult slot machine games with bonus rounds as the volatility is very high. But the reward of 2,500x your stake for a nine payline slot is excellent.

There are only two features in this slot, compared to other slot machines with bonus games. First are the free spins. When you get three or more scatter symbols, you trigger 12 free spins, and can even retrigger them once. During free spins, you can benefit from sticky wilds.

Sticky Wilds are the Wanted poster symbols, and they stick only in the free spins round. Getting one or more will not only substitute for regular symbols and have them remain until the end but will also trigger five more free spins. As such, while it can be challenging to land rewards, once you get a lucky streak, you could earn enormous rewards.

Gonzo’s Quest (Free Fall) – From NetEnt

The Bonus Round of the Gonzo's Quest Slot

We finish our list with a quest for the golden city of Eldorado in Gonzo’s Quest. In this unique game, colourful blocks fall from the sky and fill the reels, exploding whenever you win. The biggest payout you can get is 2,500x your stake with the blue blocks.

Your first bonus feature is the Avalanche feature. This mechanic causes all winning blocks to explode, and new ones will fall in their place for a chance to create more wins. Each consecutive avalanche also increases the multiplier in the top right corner so that you can get a true cascade of rewards with enough luck.

Finally, if you land three gold scatters, the door will open, and Gonzo will walk into the city of Eldorado. This Free Fall feature acts as free spins, and you get 10 spins for each bet line containing three scatters. Combined with the multipliers and avalanche feature, you can expect some outstanding prizes and fun animations.

The Top 5 Best Slot Bonus Games & Rounds

What makes slots games with bonus rounds popular is their exciting gameplay and chance for bigger rewards. Although the best bonus varies per person, popular ones are usually a mix of good rewards and fun gameplay. Here are the top 5 bonus games in online slots ranked for 2021:

🥇 Free Spins World Finn and the Swirly Spin
🥈 Holy Grail Bonus Avalon 2
🥉 Chamber of Spins Immortal Romance
🏅 Sticky Wins Jack Hammer
Avalanche Feature Gonzo’s Quest

Each of the best slot bonus games offers goods rewards and fun gameplay, adding extra fun and unique elements to their respective slot. Free Spins World allows you to utilise various mechanics to create huge winnings combinations. The Holy Grail Bonus lets you play through eight different games for more rewards.

The best bonus for you will depend on your playstyle and preference, as some are more rewarding for low-stakes players, for example. You can typically find demo versions at the popular casinos, which is an excellent opportunity to test the bonuses and see which one you like best.

Types of Bonus Feature Slots

Bonus rounds come in a variety of interesting types. Each one offers innovative gameplay and fun challenges to help spice up an already thrilling slot. Below you can find the most popular types used in bonus feature slots and what makes them a favourite staple among players.

Frequently Asked Questions From UK Readers

In this short section, we will answer all your pressing questions regarding slots with bonus games. There are many questions concerning UK players, so we will provide extra information, such as how to trigger the bonuses. Enjoy these fun slots to the fullest without worrying about any unknown details.

🤔 What's an online slot bonus game?

An online slot bonus game is a special game within a slot triggered by specific conditions such as symbols. These games often enhance the slot by introducing a new gameplay element like free spins, where you can keep spinning for prizes without spending money. Some of the best bonus games bring fresh and innovative changes to their games.

🏆 Which are the best slot machines with bonus games?

One of the best video slots with bonus rounds is Finn and the Swirly Spin for its overall incredible experience. The swirly pattern of movement is a unique innovation in the classic slot reel. Combined with its low variance and every winning combination turning into a wild, this is a truly fantastic slot that has earned its popularity.

❓ Which are the best slot games' bonus rounds?

The best bonus rounds for players vary according to their playstyle. Some enjoy getting big prizes with free spins, while others seek a more interactive game. However, Avalon 2 is a popular title among players for its variety of incredible bonus games, such as the Holy Grail bonus. Enjoy a wide selection of interactive bonus games and huge rewards.

🌟 How do I trigger the Jack Hammer slot bonus feature?

Triggering the Sticky Wins in the Jack Hammer slot is very simple. Whenever you land a winning combination on one of the 25 paylines, the symbols will lock in place while the reel spins again. Each new winning symbol will then also lock-in. This feature can also be triggered with three Free Spins symbols for more significant prizes.

💰 How do I win on the Merlin's Millions slot bonus round?

Merlin's Millions is one of the best slots games with bonus rounds thanks to the Owl Bonus. The reel fills up with owl squares, and you click on each to reveal a prize. All you have to do is keep clicking until the 'COLLECT' symbol appears. This is a great way to earn multiple prizes with one game.

📱 Can I play slots with bonus games on mobile?

Yes, all of the best slot machines with bonus games can be played at some of the best casino apps. Enjoy the fun games wherever you go on any operating system and mobile device of your choosing. Just make sure your device is updated, and you have a stable internet connection to prevent any loading issues.