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Online slots UK

By Ville Saari. Updated:

On Bojoko, you can find the best online slots for you. Online slots are the modern version of slot machines you've seen in brick-and-mortar casinos. They range from classic fruit machines to the latest video slots and jackpot games.

The problem is that there are just so many slots in the world right now. It would take over a decade to try them all out even if you played a new game every day. And that is not counting all the new releases. This is where we come in and help you find those games that are worth playing.

We have detailed reviews of over 2000 slots available at UK casinos. Use our selection tool to find the UK online slots to suit your taste.

Find the biggest selection of online slots

The amount of online slots offered by UK-licensed casinos has climbed steadily, but there are still huge differences in the size of game selection. The best slot casinos constantly add studios and games to their roster. We have compiled a list of casinos with the biggest selection of online slots in the UK. Go nuts!

guide to online slots uk

Bojoko helps you find the best slots

There are thousands of slots available online, but it's not always easy to find reliable information about them.

Our online slot listings have tons of data to help you decide what to play. They cover the basics, including the release date, RTP and volatility. In addition, there's plenty of information about the special features. Finally, every slot listing features the stats section, where you can see how this game fares compared to others.

The listings are completed by an honest analysis from our slot experts. Every single game doesn't have an expert review yet, but we're working our way through the list, starting from the usual suspects. For more information, check out our Slot reviews page.

Find the best slots

How do slots work?

When it comes to basic mechanisms, most online slots resemble the physical slot machines. As a legacy of the old "one-armed bandits", there are many familiar elements:

When you start a round, the reels begin to spin. You want to line up similar symbols to consecutive reels, starting from the left. If you get enough of the same symbol on a payline, you win. How much? That you can find on the paytable, accessed via the info pane.

Before each round, you have the option to adjust the size of your bet.


The main game area consists of vertical reels stacked together. The most prevalent layout is 5 reels with 3 symbols showing on each.

However, there are both bigger and smaller layouts. The traditional 3-by-3 reel setup is still popular in classic slots. The biggest go up to 6-by-12 or 9-by-9.


The winnings are based on getting symbols on the reels in pre-specified combinations. The highest paying symbols are usually chosen to match the theme of the game. The low-paying symbols are usually:


Slot machine paylines

Most games feature specific paylines on which you need to get rows of symbols. In most games, the paylines only go from left to right, meaning your winning combination needs to start from the leftmost reel. The longer the row of symbols you get, the bigger your win.

The number of paylines varies. Few games may even have only one paylines; most feature about 20, and some boast hundreds or even thousands of paylines.

When the number of lines exceeds the 100-mark, you can usually stop looking at the actual paylines. Instead, game suppliers speak of e.g. "243 ways to win". As long as there are the same symbols on the consecutive reels starting from the left, you're in for some winnings.

In the early days of online gambling, some slots had the option to choose the number of active paylines. However, it's quite rare now.


Online slot info button

The info pane button is usually located in the corner of the game screen and marked with one of the following symbols: i, ? or 🏆.

From the info pane, you can view the:

Check out the info pane and you'll better understand what's happening in the game.


Apart from certain jackpot slots, you can select how much you want to bet per spin. The total bet size is affected by:

slot bet size

EXAMPLE: There are 9 active paylines with 1 coin per payline and 10p coin value. Your total bet per spin is 9 x 1 x 10p = 90p.

This may sound complicated, and some game suppliers have made choosing the bet size unnecessarily confusing.

Many game providers like to goof around with coin wins. Having a thousand coins clattering to the virtual money tray may sound appealing. However, with coin size at 1p, your joy may be short-lived.

Some suppliers have taken a different approach. Instead of tweaking the coin amounts and sizes, you can just pick the total bet from a list.

After choosing your bet and starting the game, there aren't really any decisions you can make, par from certain bonus features. If you want a little more player involvement, crash gambling is the next step up.

Slot special features

Videoslots are the most popular game type of online casinos. In addition to unique themes and dazzling graphics, they come loaded with special features. These include different versions of:

Below, you'll find detailed descriptions of all special features. Use our UK slot list to filter games based on your favourite features.

Wild symbols

The wild symbol helps you create more winning combinations. It works in a similar way as the joker in poker. Whereas the joker replaces the missing card in your hand, the wild symbol fills in for the missing symbol on the payline.

The wild symbol replaces any base symbol of the game. If the same wild is on multiple paylines, it can simultaneously stand-in for several winning symbols.

However, the wild symbol doesn't replace special symbols, e.g. scatters.

In addition to standard wilds, some games feature more specialised wilds:

Scatter symbols

Scatter symbols are the slot special symbols that unlock free spins, bonus games or coin wins.

Unlike ordinary symbols, scatter symbols don't need to land on a specific payline. You only need to get a certain number of them on the reels. In many games, you need 3 scatters to launch the free spins or the bonus round.

Free spins

Free spins is a confusing term. It can refer to free game rounds that casinos use to attract new players. On our free spins page, we tell you how to get no deposit free spins. This is one of the most common forms of casino bonuses.

In-game free spins are a completely different cup of tea. You don't get them as a bonus from the casino; you win them by playing the game. You usually need to land 3 scatter or free spins symbols on the reels to start this feature.

You always get a certain amount of free spins. In some games, the exact number of scatters landed may affect the spin amount. In others, you can win more spins during the feature itself.

The spins are given in the same bet size you used on the round where you unlocked the spins.

EXAMPLE: You play with a £1 bet and win 20 spins. Every one of these spins is worth £1, landing you a total of £20 worth of spins. While you're playing the free spins, they don't use up your real money balance.

When the free spins start, the appearance of the game often changes to make them distinct from the main game. The free rounds may also have some extra perks compared to the base game. Here are a few examples:

There are also free spins games, where you can decide the exact nature of the feature. For example, you may choose between a larger number of spins with fewer extra perks and a smaller number of spins with more winning potential.

You may need to hit the feature several times to unlock all the options.

Bonus games

Bonus games are special features which often offer much bigger wins than the base game. You usually need to land a certain number of scatters on the reels to start the bonus game. In some slots, you can launch the bonus feature by paying a lump sum. This is known as Buy bonus.

Bonus games differ a lot from each other. Some may require decision making or quick reactions. The simplest and most common version is the pick-n-click type of game. You reveal coin wins, free spins and other rewards by clicking treasure chests.


Re-spins let you spin some or all the reels again without placing an additional bet.

Just like there are many kinds of wilds, there are also various types of re-spins:

Sticky wins

The sticky win isn't exactly a re-spin, but it resembles this feature class a lot. When you win, the winning combinations stay on the reels for an additional round. You need to place a standard bet, though.

Other features

Expanding reels

Expanding reels copy themselves on one or more neighbouring reels or add completely new places for symbols. This helps create longer, more valuable winning combinations.

Colossal symbols

Colossal symbols are bigger than the standard 1-by-1 symbols. They help create big clusters of the same symbol.

NetEnt's Spinata Grande is one of the most popular slots with colossal symbols.

Win both ways

In most slots, the paylines only go from left to right. You'll only get wins, if:

When you have a slot with wins both ways, the paylines can go from right to left and left to right. This practically doubles the number of wins.

The most famous slot with wins both ways is NetEnt's mega-hit Starburst.

Try different types of online slot machines for real money

Best online slots

Real money slot machines are the favourite game category for most casino players. There are many different types of online slot machines available at UK casinos.

Below, we'll cover the main aspects of these games. Discover your favourites and play slots online.

Modern video slots

Modern video slots constitute the bulk of the online casino slot games in the UK market.

Bursting with cool themes, features and graphics, these games can be very elaborate. They often feature storytelling, engaging animations and prolonged features to keep players on the edge of their seats.

There are many options to choose from, and it's not always easy to find the perfect game by trial and error. On Bojoko, you'll find:

Return to the slot selection tool to find more slots, or try our casino selection tool. You can also check out our page dedicated to New slots published in 2022.

Fruit machines

Fruit machines are some of the simplest slots available. Modeled on the physical, coin-operated pub slots of times gone by, the online versions give the fruit machine a modern spin. These are generally based on American machines, and not the fruit machines you would find in your local pub. Those games are also available, but are rarer.

Online fruit machines can be divided into two categories:

Progressive jackpot slots

Progressive jackpot slots feature a jackpot that grows until someone wins it. Whenever you make a bet on a progressive jackpot slot game, a portion of the money goes to the slot machine jackpot. The pot grows continually until some lucky player hits the winning combination.

Progressive slots offer the most lucrative potential out of all casino games out there. You can play them at most UK-licensed online casinos.

Penny slots

Penny slot machines are the budget-friendly solution for many slot fans. With a minimum bet of only 1p per payline, you can spin for hours without making a big dent in your bankroll.

Most slots now have fixed paylines. Before you venture out to play penny slots online, you need to make sure to pick a slot that allows you to select the number of active paylines.

Return to our online slot list and apply the Penny slots quick filter to see slots you can play for 1p per spin.

High limit slots

High roller slots are the best option for slot fans with deep pockets. The maximum bet goes up to hundreds or even thousands of pounds per spin. These high limit slots are a natural choice for players who aren't afraid to risk big to win big.

On Bojoko slot reviews, you can see the maximum bet and pick accordingly.

Mobile slots

Mobile slots are the mobile-friendly version of the desktop slot games. Usually, the game is 100% the same, whether you play it on your computer, smartphone or tablet.

Sometimes, the controls may be optimised for a tiny screen, making it easier to use with just one hand. Some slots are also optimised for both screen-orientations (landscape and portrait mode).

In 2022, all new releases are published on mobile. The support for Flash - a technology which used to dominate the desktop slots - was ended in December 2020. That's why practically every game studio has switched to the mobile-friendly HTML5 technology.

On Bojoko, you can find HTML5 slots by using the filter called Support all devices.

Some of the old, obscure games are going to disappear from the game libraries for good. However, many studios are re-launching their older classics in a mobile-friendly format.

Best payout slots

High RTP (Return to player) slots have the smallest house edge of all online slot games. The RTP percentage tells you the share of your bets you can expect to win back.

These are averages calculated over thousands of spins. The results within a single gaming session may vary significantly.

We have listed the best payout online slots in the UK based on their RTP. Go back to the slot list and apply the Highest RTP quick filter. You'll see the top 10 best payout online slots available in the UK.

Compete in slot tournaments online

A slot tournament is a form of casino competition that is available in some UK casinos. There are different types of slot tournaments online. In some categories, you have to hit the biggest coin win in one or over several spins; in others, you need to wager the most in a certain slot.

You can find all the casino competitions and slot tournaments on our Casino offers page.

Read online slots reviews

We have just completed a major overhaul of Bojoko online slot reviews. They are a great source of detailed, accurate information about real money slots in a format that is easy to digest.

In addition to basic information, our slot listings feature:

Check out our Slot reviews page to learn more about the review criteria and the testing process.

How to find slot casinos

Find a slot casino from our list

1. Find a slot casino from our list

We here on Bojoko have a massive list of slot casinos. You can use ready-made filters to narrow your search down or use personal filters to fine-tune it to find the best casino for you.

Read the reviews from our experts and other users

2. Read the reviews from our experts and other users

After you have chosen a slot casino, you can read what our experts and other users have written about it. Their first-hand accounts will give you a clear idea of what it's like to play there.

Go to the casino

3. Go to the casino

Every review page has a big green ‘PLAY HERE' button that will take you to the casino. That button will also activate any special bonus offers we might have for that particular slot casino.

Register and play

4. Register and play

When you get to the casino, you need to register an account. Just fill out the required information and verify your email if needed. Then you can just deposit and play your favourite slots.

Find slot casinos

Slots and responsible gaming

Gambling is always a risky activity and slots in particular are a risky game category. Understanding the games and the mathematics that go in them will help you become a more responsible player.

Slots are a great product for casinos, as they are fast games with a decent casino edge. This means that the player will likely play a large number of rounds and thus end up losing. The longer you play, the likelier it is that you lose.

Slots often have mechanics that will push you to play more. Maybe a bonus game that gets better every time you activate it or a symbol you need to keep collecting. These little hooks are there make sure you don't stop. They are there to plant the idea in your head that maybe the next spin will win big. By identifying these mechanics, it is easier to stay in control.

It is also easy to lose track of your spending when you are playing slots. A single spin is just a few seconds and with turbo mode you can spin twice every second. It is easy to see why a game like that would become a problem. Every spin has a negative statistical outcome, which means that it is in the casino's interest to make sure you spin more.

How are slots licensed in the UK?

Getting a slot from the developer's desk to the player's hands isn't as easy as you might think. There are a lot of regulatory bodies who need to make sure that every single part of the game is fair and square. This is no place for cheaters.

In the case of Great Britain, the regulator who watches over everyone is UKGC, United Kingdom Gambling Commission. They make sure that every cog in the machine is doing what it should and that the player is getting a fair treatment.

A license is always for the protection of the players.

The whole process takes many steps. Every single link in the chain needs to be checked and made sure that they work by the book. Simply put, to get a game to a player, the following needs to happen:

  1. The developer needs a remote license
  2. The slot needs third-party testing and a license
  3. The casino needs an operating license

When all these are done, then you as a player can go and play the game knowing that everything is trustworthy. The game will not try to cheat you, the randomness is actually random and that the casino doesn't manipulate any results.

On Bojoko, you'll only find online casinos licensed by the UK Gambling Commission.

Can a slot licence expire?

Some licenses are valid until they get manually revoked. For example, a developer's remote license can be taken away if UKGC gets complaints and looks into it.

A slot's license on the other hand is not indefinite. They are good for a year or two, depending on the details. After that, the developer needs to reapply for the license. This is usually a walk in the park, as the game might have not been changed since the first license application. If the game has been updated in any way, then it needs to be looked over again by a third-party tester.

When a game goes to third-party testing, every single bit of it is looked at. At the time of this article, UKGC uses iTech Labs to test the slots. They go over everything, and I do mean everything. The slot needs to pass rigorous testing and even the source code of the game is analysed.

EXAMPLE: Twin Spin Megaways needed to comply with 28 different requirements to meet the licensing standards, including things like rules and artwork, RTP, functionality, result determination, transaction displays etc.

Some other games might even need a couple of more, depending on the features and what kind of a game it is.

All of this is done for you. If UKGC wouldn't keep a watchful eye over the developers and the casinos, they could offer any kind of games they wanted. No one would ever know if they were fair and that the player even has a chance to win anything.


Online slots are the modern version of the physical slot machines you've seen in brick-and-mortar casinos. They are the most popular gambling games online and all UK-licensed internet casinos have them.

Online or internet slots have many advantages over the brick-and-mortar casino slot machines. These include:

  • Bigger game selection
  • Higher RTP = smaller house edge
  • More betting options
  • Bigger jackpots
  • More features

Check out our selection tool to find casinos with the largest selection of versatile online slots.

Online slots are very simple to play:

  • Log in to an online casino
  • Pick a game
  • Pick the bet size
  • Click the spin button

The reels start to spin together and stop one by one. Whether you win or lose depends on symbols you land on the reels and the active paylines of the game.

You can see the paytable and rules for each slot by clicking the information button once you've opened the game.

We explain this in more detail above, in the section How do slots work?

No. However, online slots have a built-in house edge. In the long run, you're likely to lose more than you win while playing them. That's why every player takes a conscious risk playing them. Just like any other form of gambling, you shouldn't play with money you're not prepared to lose.

Slots are built to be as unpredictable and random as possible. Every spin is a random event, completely independent of the results of the previous rounds.

This unpredictability is powered by a random number generator (RNG). Every RNG in use on licensed markets such as the UK is tested and authorised by independent testing agencies to guarantee fair play.

To put it bluntly, there's no way to beat a slot machine. You can win, but it's all random and there's nothing you can do about it.

Some players believe they can determine when a slot is going to pay out. Others use different betting strategies to maximise their chances of winning. This is nonsense.

Slot machines have no memory and the odds stay the same from one spin to the next, even after a jackpot is won.

Instead, you can enjoy slots for a longer time without losing too much. Manage your expectations and your spending well in an online casino:

  • Play for the right reasons. Gambling is a form of entertainment, not a way to make money
  • Set aside a gaming budget you can comfortably lose - and stick to it!
  • Keep your individual bets small relative to your overall gaming budget
  • Don't chase your losses or raise the stakes after a bad run
  • If you win big, withdraw your winnings

You'll find more info on our Responsible gaming page.

RTP or Return to Player is the payout percentage of the slot. Slots available in UK-licensed online casinos usually have an RTP of around 96%.

EXAMPLE: In a slot with an RTP of 96%, on average you win back £96 for every £100 wagered.

The RTP is an average that realises over the course of thousands of spins, meaning you probably won't win exactly £96 within a single game session.

RTP can also be used to calculate the house edge, i.e. what are the odds in casino's favour. 100% - RTP% = house edge. In the example above, the house edge is 4%.

We explain RTP and the house edge in more detail on our Casino games page.

Volatility (a.k.a. variance) describes how much the game results vary between rounds.

Low volatility slots churn out small wins at a steady pace. High volatility slots give bigger individual wins, but you may have to wait for a long time between hits.

Volatility is the opposite of hit frequency: high volatility slots have a low hit frequency and vice versa.

Use our slot selection tool to filter slots based on volatility.

When you play slots for real money, choosing the game is always a matter of personal taste. You may already have some solid favourites, but trying something new makes a world of difference.

These are the main factors to take into account when picking the best slots to play:

  • RTP
  • Volatility
  • Minimum & maximum bet
  • Special features
  • Mobile usability
  • Theme
  • Jackpots

Use our slot selection tool to find games to suit your preferences.


Find casinos with the best online slots


Ville Saari

Article by:

Ville Saari

Ville is an industry veteran, who has written thousands of gambling-related reviews and articles since 2009. He is an IT engineer with a passion for game and strategy optimisation, and to teach the world to play better.

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