Guide to Online UK Slot Machines

On this page, you will learn everything about Playing online UK slots, giving you more knowledge about the game, how it works and the best slot bonuses, before registering an account.


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Table of Contents

starIntroduction to Online Slot Machines

Slot machines are the only thing a horde of punters looks for in an online casino. They offer an unmatchable variety of vibrant themes, playstyles, and attractive bonuses like No deposit free spins, not to mention the limitless winnings that you can bring home. 

The numbers of slot machines are already huge and it keeps increasing every year across all categories. This leaves players confused as to which game they should pick and which games they should avoid. Everyone wants to make the most out of their limited gambling hours. 

That’s what this comprehensive Betkingcompare slot guide will do for you.

Online Slot machine guide

starWhich kind of slot machines exist?

Many myths and misunderstandings exist, in the way people understand online casino slots. Maybe you are one of those or just one of the newbies or a veteran trying to learn better about slot types. Either way, you have truly come to the right place.

starJackpot slot machines

Jackpot slot machines give the online casino players, the possibility of the biggest winnings accessible in the online casino community. Jackpots can easily grow to hundreds of pounds, which is why this type of slot machine can be very rewarding, and hereby tempting for players that are seeking the biggest winnings. It is important to remember that the progressive payouts only pay at the max bets.

Progressive slot machines are connected across multiple machines, games ad casinos, making the collected jackpots even bigger. After the progressive jackpot has been won, the game resets, and the jackpot will be built from scratch. The big winnings following the progressive slot machines makes them one of the most popular types of slot machine online.

On our casino review page, you will find free online jackpot slot machines, but still, have to remember that most online casino welcome bonuses don’t apply to jackpot slots.

If are you looking for an online jackpot slot machine, we recommend you to visit Mr Green or LeoVegas. Both have a great selection in their online and mobile casino, which constantly is in the amount of hundreds of thousands of pounds.

Both casinos are offering welcome bonuses for jackpot slots, but you should talk to their support, read our casino guides, or read the terms and conditions at first. Thus making sure you won’t miss out on a big jackpot due to some paper troubles.

star5-reel video slot machines.

A different type of online slot machine is the 5-wheel video slot. These are often referred to as 5-reel slots. The sounds, images, and graphics of video slots are appealing, sophisticated and designed to improve the gaming experience significantly.

As with 3-wheel slot machines, the video slots have a row of different symbols, but in contrast to the 3-wheel slot machines, there can be more than one payout line. Some video slots can have up to 100 payout lines, that you can bet on. Video slots are also based on RNG. But, most importantly they hold a lot of extra game features, like free spins and bonus games. You can read more of this below.

Video slots have multiple advantages in contrast to 3-reel slot machines. Stuff like bonus rounds, free spins, multipliers, and an endless possibility of payment options. Winnings on video slots are often in the big end, the maximum payouts and progressive jackpots can be won by a single bet.

Video slots are also a good way of beginning for new players that enjoy modern designs accessible for both computer and mobile units. You can also spend your welcome bonus on these games.

This category of slot machines has one strong leader: LeoVegas. They are always at the top when it comes to new online slot machines, free spins bonuses and free cash bonuses. this makes the players able to try more different games. Video, free spins, and bonus slot machines are fun to play, they are modern looking and a rewarding way of playing online casinos in the UK.

LeoVegas has a nice display and a strong selection of more than 400 games, inviting you to try more different casino games. Both are free to play and for real money.

starClassic slot machines

Classic slot machines may have a more humble appearance, than the majority of the new younger and more advanced counterpart slot machines, but they are still just as popular in the online gaming community. With a more simple and old-fashioned-looking appearance, the online retro slot machines still create a nostalgic feeling among many players, often due to the well-known fruit symbols, lucky-number seven, traditional-looking bars and bells.

These retro slot machines may not have as many free spins, and free cash bonuses, as their advanced descendants, but that doesn’t mean, you can’t win the jackpots at classic slot machines.

There have been major jackpot winnings at the old-fashioned slot machines just as long as the game has had its origins. The original, retro slot machines also called fruit machines, bell slot machines, and one-armed-bandits have been making poor people rich since they were invented in the 19th century.

Actually, the very first slot machines did not give any winnings at all. Well, at least not in the form of money. The whole idea revolved around giving out chewing gum. Did you hit three cherry symbols, the reward was chewing gum tasting like cherries. The same thing applied to oranges, melons, etc.

starFree spins slot machines

Experienced players usually look for easy casino free spins as they provide a longer gaming experience, due to the more spins being given away.

In the long term, free spins at online slot machines can give you the possibility of playing for free, as certain symbols land on payout lines, thus giving you additional spins. These bonuses are also a trend we have seen rising the recent years and will be expected to continue in years to come. Especially the top UK online casinos are giving more and more promotions containing bonus spins for the players on specific days as well.

You might say that these slot machines give more value for money. But they might not be the best option if you really want to blow the bank for money, as the prizes usually are in the small end. You can try the different slot machines with bonuses for free below,  before deciding on your favourite slot machine on the internet. Or before selecting your online casino of the best choice.

starModern made classic online slot machines

The same excitement and joy are also to be found at the modern versions of the old classic retro slot machines and one-armed bandits.  This is one of the reasons many still favour these old classic games, even though modern video slots, 3D slots and jackpot slots co-exist in the online casino world.

If you ever, in connection to online gambling, experience bigger joy from the more traditional casino feeling, you should check out our selection of free retro 3 bar-slot machines and the more refined classic 5-wheel slot machines on this page.

With better access to online slot machines, you have a better opportunity if play your favourite classic slots for free, or for real money, no matter where you are or when you have the time.

The selection is vast so you can be sure, you will find a broad assortment of slot machines fitting your taste, needs and budget in Betkingcompares listings of free classic slot machines to play online. It’s been made, so you can make a quick, easy but well-determined decision.

Whether you are choosing a NetEnt slot machine with a fruit theme, Microgamings popular retro slot machines with big jackpots or another classic machine from a different developer, we are certain, you are going to have a lot of fun. So let’s get going, hunting the cherries and diamonds – good luck to you, too!

starBonus slot machines

Bonus slot machines are famous for the incorporation of a featured bonus round.

This bonus round is released by certain combinations and symbols on an active pay line. The integrated bonus games are typically designed to complement the theme of the game, using lifelike graphics and sound effects, that make the slot machines more alive. Many bonus slot machines are even interactive, and function like small arcade games, that have multiple games within.

Bonus slot machines are appealing to fans of online casino games, and hereby attract thousands of players on a daily basis. Whether it is a game on a bonus slot machine or not, there’s usually one decisive reason for many players choosing slot machines online to play on a regular basis. This is caused by the combination of joy and winnings from the bonus slot machines, as this type of game usually offers big winnings and free spins to winning players.

starMulti-level bonus slot machines

Multi-level bonus slot machines are a different type of popular online slot machine for many players. The multi-level bonus slot machine consists of more levels, where each gives higher possibilities of bigger winnings and more rewards.

As you have succeeded in one level, you can move on to the next, until completing the series. If a level fails, you won’t be able to move on to the next.

LeoVegas also holds first place when it comes to multi-level bonus slot machines in the UK. Their big selection of computer-based mobile slot machines makes them leading within this type of extra features game. The best welcome bonus for multi-level bonus slot machines in the UK is a signup offer including free spins, so that you may try as many games as possible.

X of Y-bonus slot machines are winnings, you can obtain a certain number of special symbols on the wheels. This type of slot machine game is different from the free bonus slot machines, as the appearance of the X of Y-bonus feature doesn’t depend on the position of a wheel after a spin, but on the other hand the required amount of a specific symbol on a different screen.

When playing X of Y-bonus slot machines, it is expected, that you choose en of more objects from a group of objects and then add the winnings from each together. The X of Y-bonus slot machines can also be played on different levels. You will have to succeed at each level before moving on to the next.

starWhat are the best slot machines for you?

In order to win the maximum amounts from the given no of spins on a slot, the first step is knowing yourself as a player. And to do so you will have to further analyse if you are a beginner or veteran or maybe somewhere in between. Depending on that should you choose a slot to play here is how:

Slot machines for the beginner

Is it possible to be good or bad at playing online slot machines?

It really isn’t a question of whether you are good or bad at playing online casinosA newbie in an online casino tends to play the low-volatility slots. These type of games normally gives more, and small, winnings so that you can keep playing.

Depositing £20 as a new beginner, you would probably want to enjoy your money for as long as possible, exploring the different casino games and services. Maybe the casinos don’t support mobile play or are having bad customer support?

Slot machines for the experienced player

The high volatile slots can payout high winnings. At some times even higher than jackpot games! This has to do with the online progressive jackpots at UK casinos. A UK jackpot never gives more than £100.000 whereas high-volatile slots are limitless and can pay our millions. 

The negative side of the high-volatile slot machines is the fact that you can play them for a long time without any winnings, and hereby lose your money quickly. But once hitting a good combination, you will win BIG!

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starHow to select the best casino for playing slots?

Picking an online slot site can be an easy task, as it can be very hard to find the right one. Mainly there are some criteria to look into:

  1. Always introducing the latest new slot machines
  2. A big selection of different slots for mobile and computer.
  3. A big welcome bonus with small wagering terms.

Our review ratings don’t reflect the above-mentioned factors. They are reserved for live casinos, mobile casinos, and other options. Below you will find the best-performing slot sites in the UK in 2023.

starMobile casino slot machines

All the slots that you play on a casino website can also be enjoyed anywhere anytime on your mobile device using Mobile casino apps with the same smoothness and quality. Not only that you can enjoy exclusive mobile bonuses as well. Like in LeoVegas mobile casino app, you can play 2 games on one screen simultaneously and get 10 no deposit free spins on registration.

starAre Online Slot Machines Rigged?

Before starting your favourite type of online slot machine, we recommend that you look into how the math behind the game actually works. This might not be the most fun reading, but it is for sure, knowledge that can be measured in gold. Especially for inexperienced online casino players. To this point, it is important to understand that, the casinos are NOT dabbling with the machines. In this post, you can read about myths and misunderstandings when it comes to the slots.

In all online slot machines, there is a computer component often referred to as the random number generator (RNG). The purpose of this is to ensure random number sequences in the intervals of milliseconds all day long, each day.

RNGs produce random series of numbers every time you hit the spin button or the max bet button.

Any online casino in the UK has games controlled by RNGs deciding the outcome of the slot machine. These outcomes are dependent on a combination of algorithms and software. These systems deciding the outcome are never based upon spins that happened in the past. They only decide one future spin ahead.

Controls are being made by The Gambling Commission and the international organization eCOGRA. eCOGRA is an international test-specialists for different types of online products and ISO certificates.

In other words: the online UK casinos cannot cheat you!

starFairplay and RTP in Slot machines

Online slot machines that are developed by trusted companies and are available at a licensed online casino can be fully trusted. Especially, casinos with UK Gambling Commission or the Malta Gaming Authority Licenses.

These casinos often use random number generators (RNGs) to ensure that the outcome of each spin is completely random and fair. These RNGs are regularly audited by independent third-party companies to ensure their fairness.

Are slot machine RTPs fair?
Absolutely. The RTP is a fair indication of the overall fairness of an online slot game. It’s a percentage that indicates the amount of money that a player can expect to get back from a particular online slot game over a long period of time.

As per strict guidelines of the Gambling Commission and Section 240 of the Gambling Act 2005, every slot machine must show “the proportion of amounts paid to use the machine that is returned by way of prizes; or the odds of winning prizes from use of the machine”. In short, every slot is required to display the RTP percentage up-front.


The UK Gambling act 2005

star Reputed Slot machine Game Providers

Mentioned below are the popular slot machine game providers in the UK right now:

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  • NetEnt

Founded way back in 1996 in Latvia Malta, NetEnt studios boasts a huge production of over 200 games including the record breakers Starburst and Gonzo’s Quest. You will see NetEnt studio’s game titles in over 170 online casinos, giving enticing welcome bonuses. They are by far the most popular and player’s favourite when it comes to high-quality online slot games.

  • ELK Studies

Situated in Stockholm, ELK studios is one of the “Quality over Quantity” studios. The studio is the home to insanely famous slot sequence Nitropolis. Since its inception in 2013, it has developed over 40 games that you will see in top online casinos in the UK like Mr Green, where you will get an attractive welcome bonus to start with. 

  • Microgaming

Microgaming is an Isle of Man-based gaming studio that has more than 600 online casino games under its name, a majority of them are online slots. The studio is popular for slots like The Dark Knight Rises, Thunderstruck 2, Immortal Romance, and Piggy Riches Megaways. You can visit Karamba Casino to give Microgaming slots a try.

  • Williams Interactive

William Interactive has its roots attached to game development since the 1950s. The studio is seen in over 107 top online casinos and has birthed 83 slot games. You will find William Interactive coming out with new slots rarely but when they do it’s a treat for players. 

  • Play ‘N Go

This Swedish game development company was launched in 2005 and developed 238 slot machines to this day including the wildly famous Book of dead and Reactoonz. You can play Play ‘N Go studio slots at any popular UK casino. 

  • Playtech

Launched in 1993, Playtech is ranked as one of the top three gaming providers in the world. The studio gave popular slots like Thor, The Mummy, and Ghost Ride. You can enjoy Playtech slot games in a vast variety at Video Slots casino

Reviews of Slots from the best Slot developers

starAt which online UK casino should I open an account today?

This can be a tricky question to answer especially if you haven’t any reviews of top UK slot sites. Eventually, you will have to find a casino holding a welcome bonus matching your interests in play. If you are into slot machines with bonus features, you should aim for the casinos with the most recent and often-game announcements.

If you have come this far, we salute your decision of becoming a better online slot machine player. Now, you have learned the basics of RNG, eight different types of slot machine games, and which casinos match their casino bonuses with your preferences.

But there is still a thing we haven’t told you

You can play at more than one UK slot site at a time. You don’t necessarily have to have only one favourite. When signing up at multiple casinos, you will receive more regular daily free spins bonuses, and promotions. And you will be able to draw advantage of the social aspects of casino games, play the most recently introduced casino games, and if you are really smart – even be able to play casinos online for free.

Good luck! And don’t forget to visit Betkingcompare once in a while, as we are always on the move looking for that next free £20 no deposit UK casino bonus only for you!

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    FAQs: Online Slot Games UK

    Rajeev Editor

    Ask us a question

    1. What are the most popular online slots?

    Some of the most popular slots titles include the ones from Quickspin, NetEnt, and Play'n GO. Among the exhaustive list, the best progressive games are the ones from Microgaming. Look for Mega Moolah and Mega Fortune for some of the best experiences.

    2. Are online slots in the UK safe?

    The safety and security of online gamers have always been paramount. But with the rise of online gaming comes more regulations and licensing requirements are making it possible for players to trust newer online casinos.

    5. Can I win more money by playing online slots in the UK?

    The return-to-player is higher when playing online slots, as payouts are higher due to their lower operating costs.

    Online slots are also more secure, as they can be accessed from anywhere.

    3. Can I play slots in the UK on my mobile?

    Yes. Mobile gaming is the future, and it can be played on virtually any device. Whether it’s a mobile browser or a tablet, there’s a wide range of games that you can play through.

    4. Is it simple to register for slot sites?

    Just enter your details on the sign-in form and the casinos will follow up with you shortly.