How To Play Slots

By James Langley on is dedicated to helping customers find the best place to play online. Your safety and well-being is a priority, which is why all of our expert casino reviews are 100% honest and unbiased, and we highlight the key terms and conditions of every casino bonus we advertise. Whilst we accept commission from the casinos on our list of recommendations, and this may affect where they’re positioned on our lists, we only recommend casinos that we truly believe are safe and fair. is dedicated to helping customers find the best place to play online. Your safety and well-being is a priority, which is why all of our expert casino reviews are 100% honest and unbiased, and we highlight the key terms and conditions of every casino bonus we advertise. Whilst we accept commission from the casinos on our list of recommendations, and this may affect where they’re positioned on our lists, we only recommend casinos that we truly believe are safe and fair.

How Online Slots Work

Before we get into how to play slots, it’s useful to understand some of the fundamental aspects of the game. Online slot machines are gambling machines with three or more reels, which spin once a virtual button, or lever is triggered. They work much in the same way as traditional slot machines: you deposit your money, hit the spin button and wait for your symbols to match.
Some online slot machines have the same three reels, but other online slots feature five and sometimes even over nine reels. As with traditional slot machines, you must match symbols. While some online slots require a single match straight across three reels, others allow multiple symbol matches across different lines in different directions, and symbols needn’t necessarily be next to one another to win. These lines are called paylines, and you can choose how many different paylines to bet on, and how much you wish to bet.
Your bets will take the form of coins, which can be worth as little as £0.01 in real money, but you can adjust their value as you wish. Minimum and maximum coin values will differ between casinos. Symbol meanings, bonus features, winning combinations and win amounts will vary across games and details of these can usually be found in the paytable for each game.

How to Play Online Slots

Now that you understand the basics, it’s time to learn how to play. We’ve broken down a standard online slots game down into these five straightforward steps:

  • Pick your Game and Wager – Choose the slots you want to play, and decide how much you wish to bet per line. Do remember, though, the bigger your wager, the bigger the potential win. Tip: Start betting small until you get to grips with the game.
  • Pick your Lines – The lines you bet on are called paylines, and the symbols will appear along these lines. The more paylines you bet on, the higher your chances of getting a winning combination. Bear in mind that, if you set your coins at 1p for each line, and bet on ten lines, you will bet 10p on every spin. This money will be debited from your online balance automatically. Tip: Increase your chances of getting a winning combination by experimenting with your bets between each spin. Increase and decrease the number of lines you bet on, as well as the amount you bet on them.
  • Click Spin – This is the simplest part of playing online slots, simply click the spin button. You can stop the spin whenever you like, as RNG will have already predetermined the outcome. In other words, the timing of your spin will have no effect.
  • Win or Lose – Once the reels have stopped spinning, you will see if you you have matched any symbols. Your winnings, in line with the hit-rate for that game, will be credited to your online balance automatically. The hit-rate is the amount you can win on each spin. You may be given the option of playing a bonus reel or ‘free spin’ to boost your winnings. Tip: Wilds and Scatters can also be winning symbols. Wilds can stand in for any other symbols, and Scatters will generate different rewards, depending on the game.

The Different Types of Online Slots

The best slot sites in the UK cater to everyone with their collection of slots games, but what exactly can you expect to find? Let us take you through the different types of online slot games.

3 Reel Slots

These are most similar to traditional slot machines. For these slots, paylines usually form across the middle of the reels.Typically, a payline on a 3 reel slot will require three matching symbols.

5 Reel Slots

5 reel slots have the potential for a larger number of paylines around the screen, giving you more of an opportunity to get winning symbol combinations.The paylines on these slots will often light up in different colours to mark out your winning combinations clearly.

Bonus Slots

Though not available at all online casinos, bonus slots have just one possible payline in the middle of the screen. You will need to achieve the bonus symbol to win your bonus payout on these slots. These bonus symbols will vary from casino to casino.

Feature Slots

Some online casinos provide users with the chance to play feature slots, which include special symbols (often called ‘scatter’ symbols). You will need to get a specific combination of these symbols to achieve a bonus win – these will differ from game to game.

Progressive Slots

Progressive slots can work alongside any of the slots mentioned. These slots will have a jackpot that increases gradually as you play the game, which means there is more at stake the longer you play.

Mobile Slots

These have been specifically designed to give you the same slots experience on the move, whether you choose to play in a mobile web browser or download an Android or iOS app. If you’re looking for some of the highest quality Flash and HTML5 mobile slots, the award-winning Play’n Go slots might be for you. Alternatively, if you’re into classic, retro-style slots, reminiscent of Vegas real-world casinos, with the option of playing branded slots on occasion, IGT casino slots are the way to go!

Slot Gameplay Mechanics

Online slots are by far and away where you’ll find the most choice in an online casino library. And with thousands of different games to choose from, it can be challenging to get to grips with the weird and wacky mechanics you might come across. Don’t worry — we’ve got a primer below to help you get up to speed!

Bonus Rounds

At their core, slots bonus rounds are essentially any part of the gameplay which is separate from the main game. They’re usually accessed once a player completes a specific action. 

Free spins are one of the most common bonus rounds you’ll come across. These are typically unlocked by landing at least three of a certain symbol — often the scatter — on the reels, with more symbols equating to more free spins. For example, landing three scatters might trigger a bonus round of 10 free spins, while four scatters gives 15 spins, and five scatters gives 20 spins.

One of our favourite titles with bonus rounds is Thunderstruck 2 by Microgaming. Here, the Great Hall of Spins feature includes four exciting bonus rounds. The round is triggered by landing at least three scatters, filling a progress bar which unlocks the different rounds:

  • Valkyrie gives players 10 free spins with a 5x multiplier attached;
  • Loki has 15 free spins and Wild Magic, which transforms symbols into extra wilds;
  • Odin unlocks 20 free spins and the Wild Raven feature, which turns random symbols into 2x and 3x multipliers;
  • Thor gives players 25 free spins with Rolling Reels, where consecutive wins increase a multiplier from 2x to 5x.

Avalanche Reels

First introduced in NetEnt’s seminal title, Gonzo’s Quest, avalanche reels is a thrilling mechanic where lucky players can rack up long chains of wins. The premise is simple — each time a winning combination lands on the reels, these symbols are removed with new ones falling into place, giving players an extra chance to win off the same spin. 

Avalanche reels are known by many other names, including tumbling reels, cascading reels, and rolling reels. A few other games to include this mechanic are Lara Croft: Temples and Tombs by Microgaming, Da Vinci Diamonds by IGT, and Bonanza by Big Time Gaming.

Fixed and Variable Paylines

Paylines are one of the foundational elements of any slot game. After all, they directly impact how much you could win on each spin. The number of paylines varies from game to game and is dependent on how many reels and rows there are. Some titles feature fixed paylines, where you can’t change how many are in play. Starburst, for example, has 10 fixed paylines — although these are win-both-ways, paying both left to right and right to left. 

Book of Dead by Play’n GO, on the other hand, has 1–10 variable paylines. That means players can decide how many paylines to bet on per spin, allowing them to finetune their stake. While you should always gamble in accordance with your own budget and limits, it’s worth keeping in mind that the more active paylines, the more chances to win per spin.

Cluster Pays

Cluster pays slots throw out the traditional notion of paylines, instead letting players tot up wins whenever enough matching symbols land adjacent on the reels. These games are often played on an expanded reel set which is more like a grid, requiring at least five symbols in each cluster to trigger a payout.

Dragons Clusterbuster by Red Tiger is one of our favourite titles in this category. It’s played on a 9×9 grid where players hit when five adjacent symbols connect. The game also features avalanche reels, a mechanic that often goes hand in hand with cluster pays. 


Another slot mechanic switching up the payline structure is Megaways. Here, each reel can hold between two and seven symbols, which changes randomly between each spin. In Megaways slots, symbols don’t have to connect on a payline — they must simply appear on adjacent reels from left to right.

Invented by Big Time Gaming, this feature first appeared in the developer’s 2015 title, Dragon Born. There are six reels in this game, so there can be anywhere between 12 and 42 symbols in play. With the maximum of seven symbols on each reel, there are a staggering 117,649 ways to win! 

Megaways has found its way into hundreds of slots since, with many popular titles getting their own Megaways spin-offs — including Gonzo’s Quest Megaways and Big Bass Bonanza Megaways. 

Nudge and Hold

Ever been one reel off landing a big winner, but that final symbol just doesn’t want to tick into place? With the nudge mechanic, players will get to shift a reel one or several positions, hopefully completing a winning payline. 

A similar feature you might find is ‘hold’, where players can lock certain reels in place while respinning the others. Say you’re playing a five-reel slot and you landed a winning payline on all but the middle reel. You can hold the others in place and respin reel 3 in the hopes of connecting the payline and landing a win. 

Pragmatic Play has released a number of slots with the Hold and Spin feature, including Dragon Hot, Rock Vegas, and Cash Elevator.

Pick Games

Pick games are a type of bonus round where players are presented with a number of hidden symbols or prizes, which are uncovered when they choose which ones to reveal. The number of options and picks varies by game.

Blood Suckers 2 from NetEnt features the thrilling Hidden Treasure pick game, activated by landing three Golden Door bonus symbols on adjacent reels. Players then get to select from various coffins and chests. What’s inside determines whether you’ll unlock the free spins round or return to the main game. 

The Rainbow Riches series also has a number of pick games, where players can win instant cash prizes or payout multipliers. 


Most commonly found on fruit machine-styled classic slots, the gamble feature lets players double or nothing their payout each time they win. It’s that simple!

NetEnt’s Jackpot 6000 slot includes this feature, with players getting the choice to play a game of heads or tails whenever they land a winning combination. Of course, you’re welcome to collect your winnings if you don’t fancy taking the risk.

Understanding Wilds

Wilds are always a welcome sight on the reels. These special symbols can substitute for any other, giving you a little extra help to complete winning combinations.

At their simplest, they behave like any other symbol, sporadically showing up on the reels and hopefully landing you a win. But there are a range of more complex features available in the best slots titles. Let’s take a look!

  • Sticky or Locked Wilds – When these wilds appear on the reels, they’ll remain in place while the other symbols spin around them, giving you some extra chances to pick up a win. Sticky wilds usually remain locked for a set number of spins, typically 3–5; 
  • Stacked Wilds – Essentially, stacked wilds are where multiple wild symbols appear on top of together on a single reel. Many games with stacked wilds replace them with supersized symbols that take up several spaces. In some games, they’ll take up the whole reel and will even nudge into full view;
  • Random Wilds – Slightly more unpredictable, these wilds appear on the reels randomly throughout the game. Sometimes they’re triggered by special events or features, or may only be available during a free spins round;
  • Walking or Shifting Wilds – Walking wilds is a thrilling mechanic where the symbol stays on the board, moving horizontally or vertically across the reels with each spin until it reaches the edge. As it goes, it’ll present different opportunities to land winning combinations;
  • Transferring Wilds – Transferring wilds are a bit like walking wilds, moving with each subsequent spin, but the position they end up in can be anywhere on the reels. These wild symbols usually stay in play for a certain number of spins;
  • Expanding Wilds – Expanding wilds can present some big win potential. When they land on a reel, they’ll literally expand to cover multiple spaces. Most often, they’ll expand vertically and turn an entire reel wild, but you’ll occasionally find horizontally expanding wilds too. 

The Odds of Winning

In comparison to other casino games, such as blackjack or roulette, when it comes to online slots, odds have less of an impact on your potential success, and calculating odds can become difficult, taking features that increase your winnings, such as jackpot, multiplier and bonus rounds into consideration. Having said this, it is possible to work out the odds of getting a winning combination.

If the slot has three reels, which each have twenty symbols, the calculation would be 20x20x20, which reveals that there are 8,000 different potential symbol combinations. Providing you know how many times the same symbol appears on each reel, you can then calculate how likely you are to match that symbol.

If the symbol only appears once on each reel, the calculation would be 1/20 x 1/20 x 1/20, which reveals a probability of 1 in 8,000 on gaining a three symbol match.

In general, the most simple slots have better odds of winning, but this is usually accompanied by smaller payouts.

Can I Increase My Chances of Winning?

Given that online slots are controlled by random number generators (RNG), which ensure that the results of all spins are completely at random, there is little more you can do to improve your chances of gaining a winning combination than betting on more paylines and spinning more times.

You might also consider return to player percentages (RTPs) and slot variance when it comes to your understanding chances of landing a win. RTPs, sometimes called payout percentages, refer to the amount you can win back from an overall spend, and are usually between 90-99%.

These are different to hit-rates, in that they are averages which are calculated over millions of spins. Slot variance (also known as slot volatility) refers to how the slot is programmed to payout. Low volatility slots will give lots of small payouts often, whereas high volatility slots give larger payouts less often. In general, low payout percentages can cause you to lose money faster, while higher payout percentages maximise every bet you make. Similarly, if you are playing slots that pay bigger but less often, you will score winning combinations less frequently than on slots that are designed for smaller, more regular payouts.

Ultimately, though, the house edge means that casino will always have the advantage over the player. The house edge is the percentage of money that a player will lose to the casino overall, and can be calculated in line with the RTP. If the RTP is 96%, for example, the house edge will be 4%.

How Wins Translate into Real Money

So you’ve been getting lucky on the online slot machines, but what is the relationship between these online coins and real money?

In most cases, online slots will not refer to specific currencies, but rather coins. These coins will correspond with your local currency, and their value will depend on on how much you wish to bet each time. You will often have the opportunity to change the value of your coins, depending on how much you wish to bet, and possible coin values will vary between different online casinos. When it comes to NetEnt, for example, coins will automatically be valued at £0.01, and players have the option to increase this value up to £1.00 per coin.

If you managed to get a rub of the green and land a winner, you won’t always be able to access your funds right away. If you’re using bonus funds to play, you’ll often find that you have to meet wagering requirements in order to make your funds available for withdrawal. Wagering requirements are simply the amount you will need to bet in order to release your bonus winnings into your main account balance. Of course, there are plenty of no wagering bonuses available, too. While these offers don’t provide the same huge bankroll boosts that matched deposits often do, they’re a great option for players looking to get their winnings quick. It’s simply a matter of finding what works best for you.

When your funds are ready to withdraw, you’ll be able to cash out using a range of different payment methods at the UK’s top online casinos. You can rest assured knowing transactions are secure too, if you stick to playing at a licensed site. Popular payment methods include major debit card providers, as well as e-wallets like PayPal.

General Slots Tips

We’ve covered everything you should know to start playing online slots. Here is a summary of how you should approach the game:

  1. Start Simple. There are many of complex, multi-reeled online slot machines, but we recommend that beginners stick to simple 3 and 5 reel slots;
  2. Slots is a Game of Chance. Unfortunately, there’s little skill involved when it comes to online slots. Playing a game that you’re comfortable with and fully understand is the best you can do;
  3. Choose Online Casinos Wisely. Be sure that you are playing with trusted online casinos that use RNG. Choose from our list of recommended UK-regulated casinos.
  4. Bet Responsibly. Remember that a winning streak will not last forever. Set a budget before you begin playing and stick to it. Never bet more than you can afford to lose and, most importantly, enjoy it!

Frequently Asked Questions

  • Yes. Most online casinos provide users the opportunity to play their games without using any real money. You may need to create an account first, though.

  • No. All regulated UK casinos determine their probabilities using RNG, which means no time of the day is better to play online slots.

  • Yes. As long as you are playing with a licensed UK casino, you and your money will be protected under UK laws and regulation.

  • All online betting should be fun! You should always be playing for enjoyment, rather than simply chasing the highs of winning. If you think you might be playing for the wrong reasons, there are plenty of ways to seek support.

  • No. When it comes to UK regulated casinos, random number generators (RNG) determine the probabilities of winning, as well as payout percentages. These RNGs, which are checked by a third-party, mean that all results are determined at random. The RNG has no memory of previously generated results, nor any way of predicting what is to come next.

  • This will depend on the game you wish to play and your specific requirements. Check out our list of recommended UK online casinos, all of which are regulated according to UK law.


James Langley

James is a Content Writer and casino expert at, joining us in 2021 and totting up three years’ experience in the online gambling space so far. He regularly contributes in-depth guides and reviews for the site, alongside editing and refining copy. James is also responsible for tinkering with different elements of TopRatedCasinos to make it even better for our users, and has a hand in designing some of the new features we add to the site. Outside work James is a guitarist, all-round music enthusiast, and long-distance runner.

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