If you've spent any time within the online casino sector, then you'll be fully aware that there is a huge range of games to choose from. Slots have the biggest games selection of them all and it's not uncommon to see hundreds, even thousands of slots available.
It's made the industry what it is and whilst it keeps us on our toes in that we try to review as many as we can, it gives you, the players, as a good a range as you've ever had. Online casino software production has become an integral part of the casino industry, with the best game developers conjuring slots games for almost every online casino on the internet.
However, those of you who are eagle-eyed will notice that some casinos offer a very similar range of online casino games. In fact, some casinos will have the same range of games to choose from. This is because the casinos don't actually develop slot games in house and instead, get third-party casino software providers to do this for them.
This allows the casino to then pick and choose the casino software providers that it wants to use based on the database of games they have on offer. Most casinos will generally take the full range of slots games, but not always, citing that some do not fit into the product that they want to offer.
Throughout this article, we talk more about how these casino games software providers work and how they can offer some of the most engaging slot games in the industry. We will look at what works and what does not, but most importantly give you the tools to work out what's best for you. There is plenty of information about the iGaming software industry out there, but here we endeavour to sum up the best slot providers and slot software developers.
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One of the key areas that we wanted to address at SlotSource was to create a team that is dedicated to slots. These guys are able to work within some of the biggest slot software providers in the business and as a result, we can look through who's hot and who's not. When reviewing these slot game providers, here are some things we take into account:
- Game selection
- User experience
- Game design
Each online gaming software provider is different from the other. Unlike casinos, game providers have a unique range of online casino games that only they have access to. These can be slots games that are made in-house and those that are created alongside a brand.
The history of the company is something that we look at closely. We want to know their background in gambling software and what they have in their arsenal that sets them apart from the competition. At the minute there is a nice mix of long-standing game providers and a host of new-age businesses jumping on the bandwagon of platforms such as HTML 5.
What a lot of people don't know is that each of these companies needs to be licensed to make their games. For them to work with companies, they will need to be licensed by the UK Gambling Commission (UKGC) or the Malta Gaming Authority (MGA).
It's their role to then look over each online slot game that is produced and make sure they are fair and hit the numbers that are reported. The fact of the matter is that, if they fail to do this, they will not be able to publish that slot machine.
Next up we like to see if the online gaming software provider has any awards from within the industry. Generally, if they have been acknowledged by their peers then this is going to highlight they are creating good online casino games. If a wide variety of casino games is important for you when signing up for an online casino, we'll leave some recommendations below.
Once the look into the business side of things is complete, it's now time to move into the games that are on offer. It's not just the volume of games here, although this is important. We like to look at the quality for the most part and make sure that however many games are offered are of the highest standard, as well as if they are offering new online slots when they hit the market.
Innovation within the sector is now as big as any. We have shifted a huge amount of time and resources into reviewing just this area, trying to highlight what these companies are doing to break the mould and try to become the best casino software provider.
RTP (Return to Player) percentages are another key area that takes up a lot of our time. The higher this number, the better for the player, for the most part at least. Those companies that are happily taking a smaller piece of the pie are ones that are going to score well for the player. RTP is something to look closely at if you plan on playing real-money slots.
One thing we will point out in terms of RTP is that the best online casino slots aren't necessarily the ones with the highest RTP. There is a need to strike a balance between this number and the volatility of a slot that then makes an online slot "great".
Design and in-game features are the next sections that we look at. Do the games look good on a range of devices and do they offer a nice range of features that keep players coming back? Given there are so many games to choose from these days, if the answer is no to just one of these questions, then the slot game will not score well.
Seeing which casinos are hosting a game provider is another easy factor to see how good they are. If most of the top casinos are stocking their products, then you will likely see that they are worth investing in.
To wrap up our review on game providers, we move away from slots and see what other types of games they are offering. After all, the package here is important and if they standout in another area, we want you to know about it.
We want to stress that each of our reviews is constantly changing. The best game developers are bringing games out weekly, so these all contribute to the overall score. It's worth bookmarking this page where we will highlight which online casino games are new and from which casinos you can access them.
Meet Our Software Provider Expert
James has been involved with the online gaming and gambling industry for over 10 years. During this time he tested, previewed and reviewed hundreds of slot games. James loves discovering the next big thing, be it a brand new feature, a mega jackpot or being first to preview a new slot blockbuster. He doesn’t always agree with the public opinions and finds some popular slots massively overrated. His favourite ‘’underdog’’ slot is Microgaming’s Hot Ink.Read More
Regulation for any casino game is incredibly important, but even more so for slots given the sheer volume that's on offer. Before any game comes to an online casino, they are tested for fairness and only then are they legally allowed to be added to a gaming catalogue.
There are lots of companies that work within this sector but ultimately, they need to be tested and comply with a rating from the UK Gambling Commission. They make sure things like the mentioned RNG and RTP are both as have been reported and are fully fair.
eCogra is one of the most recognised independent testing bodies within the casino industry. The London firm has made it their job to test all games and make sure that they run as they should. Whilst there is no official tie to the UK Gambling Commission, the pair do work closely together and eCogra will flag games to them that don't meet the criteria.
You will notice that most reputable casinos work with eCogra and they will highlight this within the casino. The same standards are followed with the game developers as well, which again, can be checked on their website.
Other testing agencies that offer unbiased certification of slot games include Quinel, iTechLabs and NMi Metrology.
What we will add is online gaming software providers are very conscious that even a single game that flags with eCogra or any testing facility is incredibly bad for business. There is no need to pull the wool over player's eyes given the margins that they get already, but as you can imagine, there are some that have and likely will try to in the future.
It's worth noting that the industry is as safe and fair as it's ever been regarding testing and fairness. The process to develop and license new games is not an easy one, with the right people looking to make sure that players are safe.
Slots make up the bulk of the games for the vast majority of game developers. They are relatively easy to make, and they can make slight adjustments to games to make them unique.
Over the years new innovations such as 3D slots and VR slots have been introduced to the market as software providers look to set themselves apart from the competition, and new features are constantly being worked on.
The theme is one of the most common and easiest things for a developer to change. The range now is crazy and some weird games are kicking about, with everything from lumberjacks to mermaids and monkeys to deep-sea divers.
Features within the games are another pretty customisable area. For this, things like paylines, bonus rounds and free spins make them stand out, with the more the better as far as we are concerned.
RTP is another factor that we love to see improved on and generally the higher the better. However, there needs to be a balance here between the RTP and the volatility of the game to avoid simply winning your stake back with each bet and getting nowhere fast. Most players would likely rather lose a little more for the thrill of hitting big.
Branded games have soared over the last 5 years and this, for us at least, is one of the most interesting sectors within online slots. This is because the game developer now has a brand image to take into account, but also likely a bigger budget to make these games as good as they can be.
You may notice from the list of providers and slots earlier in the article that lots of the games we recommend are that of branded games. This is because they are generally better than your standard games, although not all have great RTP, so keep an eye out for that.
The youth of today would call these guys the "OG" of the gaming world. They originally set up as a fully-fledged casino back in 1994, before then turning their eye to that of game development. They are featured on more casinos than any other within the industry and one of very few that power some casinos on their own. With hundreds of online casino games to choose from, they are one of the biggest, with standout games including that of Mega Moolah (progressive jackpot), Jurassic Park and Game of Thrones.
The closest rival to Microgaming? Maybe. But NetEnt is more than just a second-place game provider and have been one of the best for several years now. Based in Sweden, the company have been able to produce a number of games that are now very much brands of their own. Two that stand out are that of Gonzo's Quest and Starburst. Both games are now heavily linked with many bonuses and welcome offers, with Starburst being the go-to game for most casinos who offer free spins bonuses. NetEnt has also been able to create one of the highest RTP's of any slot, with Mega Joker running at a massive 99% RTP.
Another Swedish company that has been about since 1997, Play'N Go are not newcomers to this sector. However, it's only been over the last 5 years that we have seen them take their online casino games to the next level. Their hard work has paid off and games like the Rich Wilde series and Troll Hunters are about as big an online slot as you will find in the business. They are best known for their stunning graphics and bonus rounds, making their games some of the most exciting on the market right now.
Another behemoth in the industry is that of PlayTech, boasting a massive 700 games in their catalogue and counting. They have been able to make a huge company from their success and they have over 5,000 employees based around the world. In terms of online casino games, it's the branded games that have allowed the company to set them apart from the rest. There are countless ones on there, but links with the likes of DC Entertainment has seen games include Justice League, The Dark Knight, Superman, Age of Gods and many, many more.
Possibly the most underrated slots game developer in the game, Yggdrasil is killing it right now. They don't have the biggest range of online casino games to choose from, but they take quality over quantity to a new level. Opening their doors in 2013 means they are still relatively young, but they have taken the technological advancements of platforms like HTML 5 to new levels. Their Vikings Go series along with the likes of Blood Moon Wilds are not just some of the best slots on their platform, but in the industry.
One of the middle-of-the-road game providers that are used as more of a filler than anything too dominant in the industry. They are another that is based out Sweden, but they work on a more limited budget and size than any of the aforementioned providers. However, they have some more than decent online slots, with the standout being that of Wild Torso. The slot was able to pick up Game of the Year at the EGR Operator Awards back in 2017, fighting off a lot of stiff competition from much bigger companies.
IGT is as big as they come when it comes to casino slot providers. They are the only one to have toppled the 1,000 mark when it comes to slots alone and also one of few that can power a full online casino on their own. The brand is huge and they have over 12,000 employees who are based all over the world. They still run a lot of brick and mortar slot machines, but in terms of their online portfolio, the best is that of Da Vinci Diamonds, Family Guy and Cleopatra Plus.
One of the best game developers that is as well known for their land-based games as their online slots, Novomatic have been running since 1980. The company have been able to make the move from land to online and whilst they haven't seen the success that they might have hoped online, they are still pretty well known. The range of online casino games is a little limited, but their biggest game is by far that of the Book of Ra (rhyme unintentional). The game has been linked with a huge range of free spins offers from dozens of casinos over the years. Other standouts are that of Sizzling Hot, Dolphin's Pearl and Lord of the Ocean.
With a catalogue of around 30 slots in total, Nolimit City is one of the smaller brands that are hooking up UK players with casino games. They do pack a punch, however, and they are incredibly interactive working seamlessly on mobile and online platforms.
NextGen was originally set up down under in Australia and over the years have jumped about between acquisitions and takeovers of their own. What this has allowed the company do is invest large sums of money into their game development which has now paid dividends, as they've got a great arrangement to choose from. Gorilla Go Wild and Jackpot Jester are two of their biggest games. They both include a huge range of their features and bonus rounds, showcasing what NextGen is capable of.
Above we've included a range of the bigger developers in the industry, but there are dozens more that we could talk about a well. These are smaller companies, but they play an important role still in making casinos as unique as they can be.
We spoke earlier about HTML 5 allowing companies to develop better games that work online and on mobile, but it's also made it much easier to create these games as well. This has opened the door for what we like to call "independent game developers" who are not part of a bigger company.
They lack a little when it comes to the size and number of games, but as there are less to work on, it means that the quality is often really high. It's not uncommon for smaller developers to pick up wins for best-slot-type awards for this very reason.
What holds them back is trying to break into what is a pretty closed shop at the top of the tree. Casinos like to have a good stock of slots on offer, so when a company is pitching a catalogue of 20 to 30 online casino games, it means more work for the casino to then get others in to pad out the rest of the site.
That being said, the smaller providers have to start somewhere, and we have been mightily impressed with some of the games that have been produced over the last few years. Below we have included a list of some of these casino software providers:
As the mobile sector continues to grow, so does the time and resources given to it from slot developers. We are now getting to a point where games are being created with a mobile-first approach for the first time, such is the impact that mobile casino is having within the industry.
Developers have to be able to offer their games on both an app platform and a mobile browser platform. This is because many casinos can access both, which is why platforms like HTML 5 are so important as it allows the developer to do this.
What we are seeing is that the quality of these mobile slots is going through the roof. Some are even being made with a one-finger setup, meaning you can use the game as if you were scrolling through your social media accounts with one finger, instead of a landscape view as if you were getting ready to play a game. Just as many people are playing at iPhone and Android devices as there are on more traditional desktops.
We are fully expecting to see the range of mobile slots continue to rise. However, it is worth noting that not all games will be copied across. Games that are older and get little to no gameplay just aren't worth the time and money to make the change from online to mobile. This is something you need to be aware of, especially if you are clearing bonuses on mobile.
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Progressive jackpots are what attracts most people to slots. They are one of the ways that you can win life-changing sums of money with a single spin. Some game suppliers specialise in progressive jackpot slots, just like another game provider might be more adept at developing a video slot. While the best game developers should offer all types of slot games, some specialise in a certain field of online gaming software.
These work as a cross-developer platform mostly and by this, we mean that the jackpots are run via the developer and not the casino they are hosted on. This means that a huge number of players get access to them and that's why the jackpots are so big.
One of the biggest of the progressive jackpot group is that of Microgaming. Their single biggest game is Mega Moolah with a top payout of almost €19 million from a single game. Other notable progressives include Major Millions, King Cashalot, Treasure Nile and Poker Ride.
NetEnt has a massive range to choose from here with over 80 progressive jackpot games spread out over several casinos. Its biggest wain is almost €18 million which came on the Mega Fortune progressive. Other notable games include Hall of Gods, Mega Fortune Dreams, Arabian Nights and Caribbean Stud.
PlayTech has a more diverse range of progressive games and they include several table games within their section. As one of the biggest slots operator of them all, it will come as little surprise to hear that, but in terms of their biggest jackpot win, it's down on the others at "just" €9 million on Jackpot Giant. Other games include Beach Life, Gold Rally, Gladiator and Funky Fruits.
The smallest of our pick, Yggdrasil are down on numbers, but for us, have the best jackpot games of any of the competition in terms of playability and graphics. The one to watch is that of Joker Millions which as a top prize of €7.8 million.
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In general, most of the top or more significant Slot Providers produce at least one slot per month, and our team at SlotSource test and review them so that we can recommend the best ones to our readers.
We also have a handy Slots Calendar which we built specifically for online slots fans to keep up to date with the latest drops, which we immediately send one of our experienced team to review for your own convenience. We recommend bookmarking that page so you never miss out on the latest slots releases, as well as details on upcoming games.
Slot Software Providers FAQ
🎰 Do slot software developers make free games?
Some casinos will allow you to access what is known as demo games, which allow you to play for free. This is not a feature that players in Ireland can access or casinos that accept Ireland-based players will be able to offer.
🎰 Why some slot providers are better than others?
It comes down to the quality of games on offer and usually the budgets that are invested in each game. The likes of Microgaming, NetEnt and PlayTech have huge budgets which not only allow them to make good games but lots of them.
🎰 Are all slot software developers safe and trustworthy?
As long as they are licensed by the UK Gambling Commission and linked with bodies such as eCogra, then yes, they are safe and trustworthy. Rest assured, we do a full background check on all of the casino software providers that we review.
🎰 Do slot developers need to be licenced in Ireland?
Yes, they must be fully licensed with the UK Gambling Commission or the Malta Gaming Authority. Without the stamp of approval from either of these two authorities, a casino software provider will have little chance of featuring at top online casinos.
🎰 Which Game Providers produce the most profitable Jackpot slots?
There is a wide range, but the biggest is that of Microgaming, NetEnt, PlayTech and Yggdrasil. It's tough to say which slot game provider might offer the most profitable slots, as most will have a mixture of different games with a variety of RTP rates (Return To Player).
🎰 Where can I play slots from software developers you mention?
All of the top-recommended slot sites we list on SlotSource stock at least one of these game providers. This includes the likes of Party Casino, PlayZee, LeoVegas, Casino Nation and 888 Casino - but feel free to check out the reviews of any individual operator that tickles your fancy.
🎰 Which slot provider is considered the best?
It’s tough to say, but Microgaming is probably regarded as one of the biggest and the best. This is based on the fact that more casinos use their product than any other game provider. A casino software provider's popularity can vary from country to country depending on the type of slots they have on offer.
🎰 Does slot software need to be downloaded?
No, you can access these via your browser or mobile device. When online slots first hit the market, it may have been a case where you might have needed to download software to play them, but modern technology has all but eliminated this.
🎰 Do online casinos feature all slot providers?
No, they will choose just several providers to power the casino. The number will differ, but usually anywhere from 5 through to as many as 30. Different casinos will partner with different software game providers, so check out your chosen slot site's library before signing up to make sure they have teamed up with your favourite slot developer!
🎰 Which Game Provider has the most slots?
PlayTech is the biggest in the industry right now with over 1,000 slots alone. Other industry leaders would include the likes of NetEnt, Microgaming and Yggdrasil. Remember, however, that slot software developers will release new titles all the time, so their libraries are always expanding.
🎰 Do all slot software providers make mobile slots?
Most of them do, yes. However, not all games from their catalogues have been copied across to mobile basically because not enough people play those games to warrant the cost of changing over, but in general, most slots are optimised for mobile devices.
🎰 Which Software Provider is known for largest winnings?
In general, Microgaming is considered one of the leaders for providing players with the largest wins, with plenty of progressive slots in their library including the infamous Mega Moolah that can pay out millions with just one spin - a real life-changing sum of real money!