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Best Online Slot Games Ireland

Last Updated: 08/02/2023

Looking to play the best real money online slot games at the best slot sites in Ireland? The variety is huge, and games have different advantages: progressive jackpots, high RTP, bonus features, and theme/design. To help you find the best slot games, we have put together an in-depth guide on the various types of online slot games you can play, as well as the top online slot sites where you can find them.

Most Popular Online Slot Games – Must Try

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Mega MoolahOh My Spins Casino 88.12% Medium Play now
Gonzo’s QuestPartyCasino 95.97% Medium Play now
Age of the GodsOh My Spins Casino 95.02% Medium Play now
Book of DeadOh My Spins Casino 94.25% High Play now
Great Rhino MegawaysOh My Spins Casino 96.58% High Play now

Types of Online Slots

Over the last few years, the online slot games sector has grown increasingly sophisticated, making them one of the most popular casino games at casino sites. Before, players who wanted to wager on online slots had to deal with low-quality graphics, tired themes and lag times that made every spin feel like an eternity. Now, however, Irish bettors have a thrilling array of high-quality slots to choose from. While there is an endless variety of themes and bonus features to cater to every player’s taste, online slot games can be broadly divided into five key categories:

Video slots | The bread-and-butter of an online casino’s game library, video slots dominate the online slots industry. These classic online slot machines began as classic 3-reel games, but have since expanded into more elaborate 5-reel slots. Video slots contain a whole host of exciting features like wilds, free spins, bonus rounds and slot symbol scatters. They even come with live-action backgrounds and innovative animations to keep you entertained for hours. The best video slots of 2023 include Kingdoms Rise: Captain’s Treasure, Wheel of Fortune, Starburst and Mega Joker.

3D Slots | Video slot players who want to kick their gameplay up a notch can do so by playing on a 3D slot. Don’t let the name deceive you - you won’t need a pair of 3D glasses to play them. Instead, 3D slots games are characterised by updated graphics, stronger narratives and a more immersive overall experience. Top 3D slots of 2023 include The Rift, Turning Totems, Gonzo’s Quest and Jungle Jim El Dorado.

Progressive Jackpot Slots | Otherwise known as “progressive slots” or just “progressives”, these casino slot games have proven spectacularly popular since first appearing in Microgaming’s 2009 slot game, Mega Moolah. Offering the opportunity to win huge prizes from relatively small stakes, progressive slots work by contributing a small portion of each slot player's stake towards the jackpot. This jackpot continually rises until a player finally triggers it. Recently, there have been several instances of players receiving seven-figure and even eight-figure prizes. Top progressive jackpot slots of 2023 include Divine Fortune, Age of the Gods and Mega Fortune.

Fruit Machines | Often referred to as “fruties”, these simplistic slot games are designed to mimic the physical slot machines you find in bars and arcades across Ireland. In their most basic form, online fruit machines feature 3 reels and a single payline in the middle. Symbols typically include classic casino imagery like fruit, bells and the number 7. Players get the option to hold or nudge reels, adding a further layer of intrigue and excitement. Some of the top fruit machine slot games Irish players can enjoy include Fruit Shop, Booming 7 and Fruit Fiesta.

Branded Slots | As Netflix subscriptions soar and the demand for themed games increases, so too has the demand for branded slots at Ireland online casinos. These quirky slot machine games are similar to video slots, but they follow a narrative based on a famous movie, TV show or band. Some of the best branded games of 2023 include Game of Thrones, Britain’s Got Talent, Rocky and Guns’N Roses.

Before getting into details on slot machines, we’ll start by jumping straight into our list of the best casino slot games online. Our experts review thousands of online slot games and below are our top picks:

Mega Moolah – RTP: 88.12%

One of the most famous slot games, Mega Moolah by Microgaming is the slot that can change your life in a single spin. Known for its progressive jackpot that can reach millions of euros (with a €1 million standard jackpot), it is easy to forget the game behind the prize. 

Mega Moolah is an exciting slot game in its own right, but there’s no doubt the progressive jackpot looms large over every spin of the reels. Speaking of reels, Mega Moolah plays on a 5x3 configuration across 25 paylines. With a free spins bonus round, this is more dynamic than other progressive slots. That is why Mega Moolah has remained a firm fan favourite since its release over a decade ago. 

Gonzo’s Quest – RTP: 96.97%

One of the most popular slot machine games available, NetEnt’s Gonzo’s Quest can be found at most online casinos in Ireland. While it launched in 2011, Gonzo’s Quest is both a classic and contemporary. NetEnt helped to create the modern blockbuster slot with features and graphics ahead of their time. 

Regular updates have meant Gonzo’s Quest has moved with the times. At the core of the game is an excellent slot mechanic running on 5 reels and 20 paylines. Jump into the Mayan jungle from as little as 20c per spin and enjoy the Avalanche reels that build successive wins up to a 5x multiplier. Also, look out for the Free Falls feature that brings up to 15x multipliers for avalanches. 

Age of Gods – RTP: 95.02%

Since its launch in 2016, Age of Gods has been one of the premier online slot games. Playtech built a game that is loaded with features, has thrilling gameplay, and a progressive jackpot. The vibrant and lively Greek mythology theme also lends gravitas to the game. You play over 5 reels and 20 paylines with four jackpots up for grabs (Athena, Hercules, Poseidon, and Zeus.)

To get one of these jackpots you will need to enter the Age of the Gods Bonus to collect one of the 4 free spins features. During these free spins, you will have multipliers up to 5x and 5 wilds on each spin. As wilds and multipliers expand, it is possible to build massive prizes.

Book of Dead – RTP: 96.21%

If Indiana Jones had an online slot, it would look like this. With its ancient tomb raiding theme and Dr Jones-like main character, Book of Dead recalls the famous Steven Spielberg movies. Play'n GO’s classic slot is one of the best examples of the adventure theme and has been grabbing new payers since launching in 2014.

Sparking plenty of clones, Book of Dead remains the pick of the bunch thanks to its above-average RTP and crazy volatility. That means you can grab frequent wins while also grabbing the occasional biggie. You spin on 5 reels, 3 rows, and 10 paylines and will be aiming to open the free spins round where you get up to 20 free spins that you can retrigger. 

Great Rhino Megaways – RTP: 96.58%

Great Rhino Megaways by Pragmatic Play is a modern classic that made its debut in 2020. It builds on Pragmatic’s growing reputation for excellent visuals with innovative features. Slot players spin on 6 reels covering up to 200,704 paylines thanks to the Megaways mechanic. It also has a Tumble feature where winning reels fall away to be replaced by more symbols. 

As you stack winning combinations, the prizes can get large, even in the base game. Even so, the free spins round is where the massive wins await, with up to 15 spins on a 10x multiplier available. In this bonus round, you also get Unlimited Win Multipliers that increase on each winning spin. 

Basic Slot Rules

Finding your perfect match is easy thanks to our handy comparison tool. Find the online casino that suits your taste, click on the link to visit the site and set up an account by following these steps:

  • Click the button that reads “Sign Up”, “Join Now” or “Register”.
  • Provide your personal details, select your username, choose a strong password and select EUR as your currency.
  • Agree to the terms and conditions and confirm your age.
  • You will need to verify your email address by clicking on a link, and confirm your ID by following a KYC procedure. You generally need to provide a copy of your photo ID and proof of address.
  • Choose your online slot bonus (if applicable). Make sure to read the terms and conditions of the bonus you select.
  • Visit the cashier and make a real money deposit using your preferred payment method.
  • Select a casino game that appeals to you, paying careful attention to the payout table. If your welcome bonus has a free spin element, make sure to choose a slot from the list of applicable slot games.
  • Set your bet and hit the spin button. Set the maximum bet per line if you are playing on a progressive jackpot slot.
  • Continue gambling until you decide to make a withdrawal. To do so, head to the cashier.
  • Choose your preferred withdrawal method, enter your amount and confirm. A typical online casino will require that you withdraw using the same method you used for your deposit.
  • Since requests take time to process, withdrawals are never instant. However, the wait times should be made clear in the terms and conditions.

Slot Rule Variations

Online slots are a diverse group of games that do not really fit into a single niche. Rules can vary depending on the features of the game, its jackpot, paytable, and genre. For example, slots will have different betting limits that control the minimum and maximum wager you can make per spin. To make it easier for players, software providers add gameplay sheets to all online slots to give an overview of the rules.

How Slot Games Work

In many ways, casino slots games are the video games of the casino industry. These are games where you bet on the outcome of a “spin”. That spin occurs on a set of reels that cover a specific number of rows and paylines. Reels must spin and match a predetermined set of symbols if you are going to win. Reel outcomes are always random, which means you need no specific skills to play online slots games. 

Understanding the Reels

Reels are the spinning component of a slot game and are the heart of the experience. Reels feature various symbols that have a value attached to them. Some symbols are more valuable than others and you need to match symbols to create winning combinations. During gameplay, the reels on a slot spin and stop on a random combination of symbols, which may or may not be a winning combo.

Slot Paylines – How Do They Work

In simple terms, a payline is the line on which a payout is given if there is a winning combination. Every slot has X amount of paylines, whether it is 1 or 200,000 (10 to 25 is most common). You can only win prizes on these paylines. This means you can only win on the paylines you wager on. So, if there are 20 paylines and you bet on 10 of them, you can only win if a combination lands on one of the 10 active paylines. 

Slot Game Bet Sizes

Slot games Irish players can access at online casinos have a wide spread of bet sizes. Games allow you to wager anywhere from €0.01 to €250 per spin, with a normal spread of between 20c and €100. Most software developers will use bet limits that are welcoming to all kinds of players. That means budget players and high rollers can enjoy most online slot games. 

Slots Game Bonus Features

Spinning reels endlessly on a game can get boring quickly, which is why iGaming software providers add all sorts of features to their online slots. You can find exciting base game dynamics, rewarding high-value symbols, free spins, Respins, and bonus rounds. It is these features that keep online slot games interesting.

Bonus Games & Free Spins

While not all slots have bonus games, most do because they are great for maintaining excitement during gameplay. More importantly, a bonus round will act as a barrier of exclusivity for winning the most lucrative prizes. Players need to land a specific combination of high-value symbols to enter a free spins or bonus round. 

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Wild Symbols

A standard high value on most online slot games is the wild. In its basic form, the wild will substitute any symbol and replace it with a useful symbol on an active payline to build a winning combo. Some slot games online will add extra features to wilds, such as Expanding Wilds. These are wild symbols that expand across other symbols or a whole reel to form winning combinations. 


Another high-value online slot symbol that you get in the base game is the scatter symbol. Sometimes a combination of winning scatters will offer a payout in the base game. However, most online slots use scatter symbols as a gateway into a bonus/free spins round. Usually, you need three, four or five scatter symbols to open the bonus and the number you have determines how many free spins you receive. 


Developed by Australian slot creator Big Time Gaming, the Megaways mechanic is an expanding reels feature popular on many slots games. Each Megaways reel holds a differing number of symbols (e.g., 3x4x4x3) with the number of symbols decided at random before a spin. If the maximum number of payways are open, you can have potentially hundreds of thousands of ways to win. 

Cluster Pay

Cluster Pay is a mechanic created by NetEnt for its Aloha online slot, but has since become available on hundreds of games. With this feature, slots hold matching symbols across all reels, lines, and positions, essentially expanding the symbol to cover multiple lines/reels. Importantly, the symbols must sit next to each other on all four sides for a payout. The bigger the cluster you build, the larger the prize. 

Progressive Jackpot Slots

Progressive jackpot slots are games that do not have a fixed top jackpot. Instead, the jackpot expands over a network each time a bet is made on the slot. This means all versions of the same slot across all online casinos and all player bets. Over time, the jackpot can become massive – running into millions of euros – until one lucky player with one random spin wins it. Once the jackpot is hit, the progressive accumulation starts again. 

What Makes a Good Slot Game?

There are hundreds of good slot games available, dozens of excellent ones, but only a smaller collection of genuinely top-tier slots. Some games are good because they do one thing amazingly well, while others are excellent because they offer a few crucial factors. As for the top-tier slot games, they tick every box and offer a complete experience. 

  • Graphics/Sound: Slots are the entertainment games of the casino industry, and immersion is hugely important. A quality slot will have outstanding visuals featuring innovative graphics and animations. Furthermore, the audio track will be dynamic and interesting to make the game even more immersive.
  • Theme: There are dozens, if not hundreds, of different slot themes out there. Some have become gold standard genres, such as mythical cities, ancient civilizations, adventure, fruit machines, and so on. When looking for a good online slot, the best developers will do the theme/genre justice.
  • Payout: The Return-to-Player (RTP) number shows how much a game will pay back to players on average. An RTP of 96% is average for online slots, so any game over this number will provide more frequent wins that may be smaller. Lower RTP slots will provide less frequent wins but may pay out bigger prizes.
  • Features: The best slots do not always need to be loaded with features, but it certainly helps. Basic online slot games can be great, but developers need to work harder to make the base game exciting. Top slots often have functional and enticing features such as free spins, multipliers, bonuses, and more.

Best Slots Software Providers

The online casino industry is powered by a wealth of extremely talented software providers. The sheer volume of developers fighting to release the year’s most exciting online slot game results in a win-win for the player. Not only do you get a huge selection of both real money and free slot games to choose from, but the fierce competition results in slot games that are continually improving with the latest cutting-edge technology. These are the most prominent casino slot games providers:

Microgaming | The Isle of Man-based firm is one of the world’s largest providers of online slots. It supplies hundreds of desktop and mobile slots, including Mega Moolah, Game of Thrones, Mermaids Millions and Thunderstruck II.

Playtech | What do Superman, Top Gun and American Dad have in common? They are all online slot games produced by Playtech, an innovative software developer known for creating exciting and high-quality branded slot machines. The software giant is also famous for producing Age of the Gods and Frankie Dettori’s Magic Seven, among many others.

NetEnt | This Swedish software supplier is responsible for creating some of the best online casino slot games of all time, including Starburst, Gonzo’s Quest and Mega Fortune. It has also produced a line of incredibly popular branded video slots, one of which is Gordon Ramsay’s Hell’s Kitchen. Not only are NetEnt’s slot machine games a huge hit with punters, but NetEnt casinos are also very popular among Irish players.

Play’n GO | Yet another developer with Nordic roots, Play’n GO is a Swedish software company with a myriad of successful casino games to its name. Some of Play’n GO’s most notable hits include Troll Hunters 2, Book of Dead and Mystery Joker.

IGT | International Game Technology is a multinational software firm headquartered in London, with further offices located in Las Vegas, Rhode Island and Rome. A pioneer in the field of branded video slots, IGT is the brains behind such popular games as Family Guy, Da Vinci Diamonds, Pharaoh’s Fortune and Cleopatra.

SG Digital | After acquiring top slot developers NYX Entertainment and NextGen, the digital division of Scientific Games has become famous for producing a range of thrilling casino slot games with exclusive bonus features. Top titles include Raging Rhino Megaways, Lucky Lanes and Prisma Blast.

Novomatic | Celebrating its 40th birthday in 2020, Novomatic began as a producer of physical slot machines for brick-and-mortar casinos. Now, this Austrian software provider works with several of the top online casinos in Ireland to release new video slots on a regular basis. Notable games include Sizzling Hot, Book of Ra and Lord of the Ocean.

Betsoft | Equally as famous for its broad selection of table games as for its extensive library of online slots, Betsoft is a software firm with a particular focus on mobile casinos and cinematic 3D slots. Alongside quirky releases like The Slothfather and Good Girl Bad Girl, Betsoft also offers an exclusive full-featured casino management platform.

Slot Payout and RTP

One of the most crucial elements any slot player must familiarise themselves with is the Return to Player (RTP) percentage of a game. The RTP refers to the amount of wagered money that a particular video slot, progressive jackpot or casino game will return to the player over a prolonged period of time. Essentially, the RTP refers to the house edge. Barcrest’s Rainbow Riches slot, for example, has an RTP of 95%. This means that the average player will eventually get back €95 for every €100 staked.

But alas, it’s never quite that simple. Since online slots are a game of chance, there is no guarantee that a machine will pay out in a certain pattern. Some players may generate a profit while others make a loss. Though the RTP gives you an idea of the returns you can expect, you shouldn’t use it as the sole basis for your gameplay. That being said, you should try and find slots with as high an RTP as possible. NetEnt’s Mega Joker has an RTP of up to 99%, while Jackpot 6000 reaches as high as 98.8%, making them some of the best online slot games for Irish players.

When testing out the free slot games at a top online slot games casino, you will be presented with a payout table. Here you will find the symbol values, special values and paylines, along with explanations of game features and any relevant jackpot information. Prizes will usually be listed as a cash amount or a multiplier. For example, if you see “100x” appear on the reels, it means you stand a chance to win 100 times the outcome of your single-line bet. Other paytable features include details of the bonus round (if there is one) and the minimum/maximum prizes. You can use this information to determine your projected payouts when playing real money slots.

Slot RNG (Random Number Generator)

A random number generator is used to calculate the result each time you hit spin on an online slots game. An RNG is also used on physical slot machines found in casinos and arcades, and it is also used to determine the results of online casino table games like roulette and blackjack. Every time you set the reels spinning, the RNG software underpinning the game will produce a number at random.

This random number goes through the game software and produces a tangible result, leading to a win or a loss for the player. All licensed online casinos in Ireland fall under the jurisdiction of the Malta Gaming Authority, which monitors the RNG technology that Irish casinos use to ensure the result is not affected by activity outside of the game engine. Whether you’re playing on a video slot, progressive jackpot or a real money table game, RNGs make sure that the outcome is fair and random every single time.

Slots Selection at Online Casinos

There are several trustworthy casinos that offer attractive welcome bonuses, slick software and great customer service. What often sets them apart is game variety. No two casinos are the same, and you will find a much broader choice of exciting slot games at the best online slot games sites. With a wealth of options to choose from, players in Ireland can browse through a variety of online casinos and register at a site with a great selection of online slot machine games. 

While some players prefer a smaller, more streamlined selection of carefully curated titles, spinning the reels of the same set of slot games can brow boring after a while. The best online slots sites list thousands of different games, stocked by multiple software providers that range from industry titans like NetEnt and Microgaming to small, independent studios.

History of Slot Machines

  • 1895: The first mechanical slot machine was invented by Charles Fey; it was known as the Liberty Bell.
  • 1907: Herbert Mills developed the Operator Bell, the first slot machine to use fruit symbols.
  • 1910: Slot machines were now entering mass production. Europe alone had 30,000 machines.
  • 1931: Nevada legalized gambling leading to the rise of Las Vegas and the slot machine.
  • 1963: Bally launched the first fully electronic slot machine, Money Honey.
  • 1976: The first true video slot arrived, created by Walter Fraley and called Fortune Coin.
  • 1986: IGT developed the first land-based progressive jackpot slot called Megabucks.
  • 1994: Microgaming became the first developer of online iGaming software, including slots.
  • 1995: Internet Gaming Inc became the first online casino.
  • 2000+: Since the turn of the century online casinos and slots have become more sophisticated, overtaking land-based games as the gambling preference for people around the world.
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