Online Slots: From Classics to New Releases

Online slots are the centrepiece of every UK casino site that we promote on our platform. They take up most of the lobby, attract the biggest audiences, and often deliver the most memorable wins. And here is why. According to the UK Gambling Commission’s latest “Operator Data to March 2025”, slots gross gambling yield (GGY) increased by 11% year-on-year. For that quarter, slots accounted for £614 million of GGY, with about 22 billion spins/bets placed.

From simple three-reel fruit machines to vast Megaways adventures and life-changing progressives, they cover every mood and taste.

Players often start with the familiar — the slot they once had a big win on, or the one with symbols they recognise from high street arcades. But curiosity keeps the market moving. New slots appear weekly, and almost every UK casino highlights them in a dedicated “New Games” section. Not all are genuinely new, of course.

Some are variants or reworks of old favourites, but the mix of genres, features, and stories shows how creative this part of gambling has become.

The Different Faces of Online Slots

The simplest slots still get played. Three-reel classics like Mega Joker (NetEnt) keep the nostalgia alive with cherries, bells and retro wallpaper, but they’re not just for show. With an RTP close to 99%, Mega Joker is among the best-value slots in existence. Its Supermeter Mode, where bets climb up to 200x your coin value, makes it more volatile than it first appears.

Most of the lobby space, though, is taken by five-reel video slots. These are the modern standard, combining strong themes with dozens of paylines, wilds, scatters and bonus rounds. Book of Ra Deluxe (Novomatic) is a good example of a super popular hit in the online slots world. Ten paylines and expanding symbols make it simple enough, but the Egyptian imagery and free spins round have helped it stay popular for years. Thunderstruck II (Microgaming) does something similar with Norse mythology, adding multiple free spin modes linked to different gods.

Then there are the Megaways titles, an invention of Big Time Gaming. They randomise the number of symbols on each reel, creating anything from a few hundred to over 100,000 ways to win per spin. White Rabbit Megaways pushes it further, expanding up to 240,000 paylines in its bonus mode. It feels less like a slot and more like a dynamic puzzle, and explains why Megaways has become a genre of its own.

Finally, the progressives. These are the real money high RTP online slots most associated with record-breaking wins. A percentage of every spin goes into a jackpot pool, which keeps climbing until someone lands it. Mega Moolah (Microgaming) is the most famous, having paid out £13.2 million to a UK player in 2015. Playtech has its own answer with the Age of the Gods series, linking multiple myth-themed slot games to a shared set of jackpots.

Features That Change the Game

Developers of the slot machines for online sites are constantly adding features to keep players interested. Some are now so common they feel standard:

• Cascading reels, where winning symbols disappear and new ones fall into place (Gonzo’s Quest).
• Expanding wilds that stretch across reels.
• Sticky wilds that hold in place for several spins.
• Multipliers that boost payouts.
• Free spins that add a second layer of excitement.

Other online slots take more risks. Wild Cauldron (Quickspin) builds paylines as the reels expand, offering up to 200,000 ways to win. Jokerizer (Yggdrasil) strips everything back to a carnival design, where just two jokers trigger mystery wins. Ugga Bugga (Playtech) breaks every convention, splitting spins into ten mini-reels. It looks odd, but with a 99.07% RTP, it still has a loyal following.

Old Favourites Still Holding On

Despite hundreds of releases every year, some games never disappear.

• Blood Suckers (NetEnt), a vampire-themed slot with 25 paylines, remains a cult favourite for its gory “Vampire Slaying Round” bonus and high 98% RTP.
• Cleopatra (IGT) has been a staple for decades, pairing simple five-reel gameplay with multipliers and free spins.
• Book of Ra Deluxe keeps drawing players back with its expanding symbols and straightforward design.
• Thunderstruck II still competes with newer Norse-themed games thanks to its layered bonus modes and strong visuals.

These classics survive because they strike a balance: familiar enough to feel safe, but with features that still make spins engaging.

What’s New in 2025

Innovation is what keeps the slot market alive. Developers like Pragmatic Play, Relax Gaming and ELK Studios have all pushed out fresh titles this year.

• Zombie School Megaways (Pragmatic Play) leans into humour, blending horror with slapstick and offering wins up to 10,000x.
• Kraken’s Cove (Relax Gaming) uses a sea-monster theme, with “Ship Wild” bonuses that feel genuinely new.
• Elysian Gold (ELK Studios) revisits Ancient Greece with six bonus features and a max win of 25,000x — high volatility but with enough action to keep people invested.
• Blazing Bison Gold Blitz (Pragmatic Play) takes the American prairie theme and adds stacked wilds across 4,096 paylines.

Some of these will stick; others will fade. But together they show how wide the market is and how often developers test new mechanics.

Progressive Jackpots and Daily Drops

For many, slots are about more than steady play. The chance of hitting a huge prize, even if unlikely, is part of the attraction.

Mega Moolah has set the bar for progressives, but Playtech’s Age of the Gods and PowerPlay Jackpots series show how shared prize pools can be spread across multiple themes. Each spin contributes a fraction to the prize, and jackpots can fall at any time.

Daily Jackpots, offered by sites like bet365 and PlayOJO, take a different approach. They guarantee a payout before midnight, creating more frequent but smaller jackpot wins. For players, it means big wins feel a little less out of reach.

Online Slots Themes and Stories

Slots succeed when they tap into cultural touchpoints. Egyptian tombs, Norse gods, vampires and wild west settings dominate, but every year sees new spins.

• Desert Fortunes (NowNow Gaming) updates the Egyptian formula with crisp design and solid mechanics.
• Buffalo King (Pragmatic Play) goes big on wild west wildlife, with 4,096 paylines and impressive graphics.
• Who Wants to Be a Millionaire Megaways (Big Time Gaming) proves how well TV tie-ins can work, adding 117,649 paylines to a familiar quiz format.
• Rainbow Riches Pick ’n’ Mix (Barcrest) is another example of a slot growing into a series, with sequels and spin-offs keeping the brand alive.

Even when themes repeat, the features and style keep them from feeling identical.

Playing Across Devices

One reason slots dominate online gambling is how well they fit different devices.

On desktop, animations and backgrounds fill the screen, making games like Wild Cauldron or Thunderstruck II immersive. On mobile, portrait mode takes over. Titles such as Jokerizer adapt especially well, allowing one-handed play on the go.

Most UK casinos now focus on mobile-first design, whether via dedicated apps (bet365, 10bet, Mr Play) or optimised mobile browsers. This flexibility is one reason real money online slots remain the most-played casino games in the country.

Where to Play Slots Online For Real Money? Our TOPs for UK

The choice of casinos is as broad as the games themselves. Some of the most reliable operators include:

• bet365 Casino – Known for its mix of new releases, classics like Book of Dead, and strong progressive coverage.
• Spin Rio – Bright design and heavy focus on new games, with plenty of Megaways titles.
• Pintit – new sites with real money slots
• 247 Bet Casino – another brand new slots site with 175 real cash exclusive titles
• Mr Play – Strong on jackpots and bonus offers, including Mega Moolah.
• Rialto Casino – Smaller, but with curated slots like Rialto Reels.
• The Vic Online – Brings the atmosphere of the London casino to the web, complete with exclusive bonuses.

These slot sites are licensed by the UK Gambling Commission, meaning all slots are independently tested and payouts verified.

Good Online Slots With High Return to Player Ratio

Note: RTP % indicates the expected payout for every £100 wagered. Higher RTPs provide better value for the player. New slot sites like Moon Games and Vegas Spins offer high payout slots and promotions like up to 777 Free spins.

Blood Sucker

This vampire-themed classic from NetEnt boasts a 98% RTP and is a low-volatility favourite for punters everywhere. There are 5 reels and a 1,014x maximum win. This game is stocked in the bet365 lobby, and once you have played this, there are a few other similar titles that might generate interest, such as Blood Shadow, Wild Blood and Wild Blood II.

Back to Blood Suckers, and if you match three or more symbols across one of the twenty-five fixed pay lines, you will land a win. The famous Vampire Slaying Round is unlocked when you land 3 of the stake and hammer bonus symbols. A gory, ghoulish giant of the genre and great value!

Ugga Bugga

Ugga Bugga from Playtech has a good 99.07% RTP and has an unusual setup. 10 sections, each with 3 symbols, give the game a unique feel. The only way to win is to line up 3 of the same symbols in one section. So essentially, you get 10 times to win every spin.

There are chances to hold and spin, giving Ugga Bugga a pleasant retro feel. Symbols include masks, drums and hats. There is no jackpot, and volatility is low, but Ugga Bugga offers new punters fantastic value and a great foothold in the online casino door.

Mega Joker

Another NetEnt creation, this all-time favourite has a staggering 99% RTP. The background and general feel is camp and fun, with potted palms and vintage wallpaper added to the gaiety.  Symbols include the classic cherries, bells and watermelons. The minimum bet is anything from 1p to £2, so Mega Joker will suit all comers. Available at all reliable casinos, including Rialto, this has quickly become a fan favourite.

A Super Metre Mode allows you to bet up to 200x your coin value per spin. 

Thunderstruck 2

This high RTP slot from Microgaming has a 96.65 RTP% and is set across 5 reels and 3 rows. Bonus features like Wild Storms and the Great Hall of Spins can help you reach a maximum win of 8,100x. The theme covered is Norse mythology, so don’t be surprised to see Thor pop up and cause mayhem.

Book of Ra Deluxe

One of the best payout online slots by Novomatic is another for-the-ages game that pops up everywhere, with a highly respectable 96% RTP. Design-wise, it is a classic 5-reel, 3-row, 10-payline set-up, and punters have fallen for the Egyptian-themed design, replete with symbols of scarab beetles, pharaohs and Horus.

The Bonus round contains the Expanding Symbol that can cover three symbol positions. You’ll go ga-ga for Book of Ra Deluxe which can be played at most online casinos, including All British Casino.

Jokerizer

This slot with a fast payout percentage comes from the Yggdrasil stable and has an RPR of up to 98%. Carnival-based Jokerizer comes in 22 languages and has an enhanced portrait mode for mobile devices, making it ideal for gaming on the go. It is high-volatility, has a maximum win of £60,000, and you only need 2 Jokers for the mystery win in bonus mode.

Undoubtedly a cheeky classic that continues to resonate to this very day.

Wild Cauldron (Quickspin)

Among the best payout online slots in the UK, the Wild Cauldron game arrived in 2020 and is a 6-reel, 4-row dream with 4,096 ways to win. The RTP % of 96.06 is not too shabby either.

Play the bonus round, and you can expand the game to 8 rows and over 200,000 ways to win! Look out for monsters and potions in this bubbling beauty.

White Rabbit Megaways

The next fast payout slot title by Big Time Gaming is a trip into Alice in Wonderland world and has a very decent 97.77 RTP %. With potentially over 240,000 pay lines, this high-volatility thrill ride takes you through the looking glass. The reels are full of grinning Chesire Cats and the Queen of Hearts. Curiouser and curiouser. Here is a list of the best Megaways slot sites.

Dead or Alive 2

This is a new riff (2019) on the gunslinger classic from NetEnt, with a very decent RTP % of 96.82. It is only a 5-reel, 3-row structure with 9 pay lines, but it can pack an over 111,000x pay-out punch. There are scatter wins, sticky wilds and the famous High Noon Saloon and Train Heist Free Spin games. 

Buffalo King

Looking for the top payout online slots UK casinos can offer? This is another wild-west classic from Pragmatic Play. With an RTP % of 96.06, punters love the option of personalising their game via the player interface. There are 6-reels, 4-rows, and stakes can range between 40p and £60.

The graphics and vividness of the background are superbly rendered, and Eagles, coyotes, and cougars abound in this high-volatility thriller. Mr Play has stocked a few versions of this, including the originals and Megaways incarnation, so check them out!

Blazing Bison Gold Blitz: High Volatility & Rich Features

Blazing Bison Gold Blitz is a high-volatility video slot, providing an opportunity for massive wins, although they may be less frequent. It offers six reels with a whopping 4096 ways to win. With an RTP of 96.00%, this game provides a favourable return rate. The real attraction, however, is the game’s features. Wild symbols can substitute for other symbols to create winning combinations, and Free Spins offer more chances to win without additional stakes.

Cleopatra: Balancing Frequency & Features

Cleopatra presents a medium volatility video game, balancing frequency and size of wins. It features five reels and 20 pay lines, with an RTP of 95.02%. Cleopatra video slot also offers several exciting features. Multipliers can exponentially increase your wins, Free Spins provide additional chances to win without extra bets, and Wilds can fill in for other symbols to create winning combinations.

The best gambling websites for playing video slots on our list are: Unibet, bet365, Spin Rio, Videoslots.com and GrosvenorCasinos.

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