Best Slot Sites in 2021
Looking for the top slot sites in the UK? Our experts have handpicked the very best that stand out from the competition.
Discover the finest slots bonuses and popular games with the highest payouts. From demo slots to tournaments and exclusives, we reveal how we rate the best slot sites so you can make an informed decision.
Top 13 UK Slot Sites
These casinos rank highly based on what we look for. We analyse what each one has to offer and go into detail on the different types of slot sites available.
They all list similar games but some will have different gaming providers to others. This will make for a unique experience, especially with some operators producing their own exclusive titles.
Best Online Slot Sites by Category
Each player will have their own preference when looking for online casinos with the best slots. But who offers the better ones? Discover the top slot sites by category.
Some players will want games with particular bonus features, and others may want titles from a specific supplier. We’ve expanded on each of the categories below to help you make an informed decision.
Online Slots Bonus for New Players
The best welcome promotions are often those that have a bonus relating to slots. With many offers having a 100% wagering contribution set for them, it’s no surprise to see slots utilised frequently.
Free spins bonuses are the most popular ones you’ll find associated with different types of slots. Players will typically come across UK casinos offering promotions for Starburst or Book of Dead, but many bonuses are also valid on Microgaming, NetEnt, and Big Time Gaming slots for example.
Slot Sites with the Highest Payouts
The best slots sites for payouts are typically those that have a wide range of games to choose from. Although much depends on the providers listed at each UK casino, to have numerous slots listed with an RTP (Return To Player) of 96% or more is recommended.
Most licensed UK casinos list the percentages on their site. Players can commonly find these figures by going to the informational section of each game, but this can be time-consuming.
Some operators go one step further for their customers and have a dedicated page that lists the RTP for each slot they have. STS Casino is one example, and it makes life so much easier if you want to know the details for multiple games.
100% up to £100
18+ New customers only • Deposit method restrictions apply • Min £10 deposit • Bonus code CWBUK100 required on deposit • The max bonus available is £100 • 35x bonus & deposit wagering within 7 days • Selected slots only • Full T&Cs Apply. #ad
Slots with the Best RTP
It’s not easy knowing what online slots pay out the most. The higher the RTP, the better in terms of having more chance of winning over a longer period of time.
Here are 10 leading slots with some of the highest payout percentages:
- Goblin’s Cave – 99.32%
- Mega Joker – 99%
- Jackpot 6000 – 98.9%
- 1429 Uncharted Seas – 98.6%
- Dr Jekyll Goes Wild – 98.20%
- Jackpot 3×3 – 98.10%
- Jokerizer – 98%
- Ragnarok – 98%
- Blood Suckers – 98%
- Rainbow Riches Fortune Favours – 97.75%
Best Low Wagering Slot Site
An operator may have 2000+ slots available, which looks great on the surface. But if the promotions come with unrealistic terms, it’s suddenly a casino that might not be of interest. Players want to see a slot site with low wagering requirements on their bonuses.
50 FREE SPINS
50 Free Spins
New 18+ UK Players • Min deposit £10 • Spins valid only on Starburst • Spins expire in 7 days • Payment method restrictions apply • 10x wagering req's on free spin winnings • Full T&Cs Apply. #ad
Some of the best slot sites will have no wagering bonus offers, although these are much rarer than most other promotions. This is simply where you can withdraw any potential winnings from free spins without having to turn the amount over.
Betfair has 50 wager-free spins as part of their welcome offer, but make sure you read the full terms before committing as it requires a promo code.
No Deposit Bonus
18+ new customers only • No deposit bonus requires promo code CASF51 • Min deposit for deposit bonus is £10 • Deposits made with e-wallets (Neteller, Moneybookers etc.) are not valid • Wagering requirements (x45) apply • Some games contribute less to the wagering requirement, some games contribute nothing • The maximum stake on your Casino Promotional Balance is £5 • Full T&Cs Apply. #ad
No deposit slot sites are quite rare but they offer players the opportunity to try out some popular games after registering and before a real money deposit is required.
These types of offers are often free spins on leading games such as Book of Dead or Starburst. But there are one or two that have a monetary bonus that players can use on numerous slots. 777 Casino is one example where new players are rewarded with a £77 no deposit offer.
77 No Deposit Free Spins &
18+ New UK players only • Free spins £0.25 per spin, claimed within 48 hrs, expire in 14 days, wins capped at £20, exc. JP win • £20 min deposit • Bonus wins capped at £500 • 30x wagering within 90 days • Full T&Cs Apply. #ad
Best PayPal Slot Site
PayPal is a popular payment choice at a UK slot site. Payouts are often processed within a few hours, and the security levels are so high that no personal information is ever compromised.
The top operators will include PayPal in their welcome offer. Not all sites list them, but if they do, there are some that exclude e-wallets from promotions. Always check the terms of the offer to see if this is the case.
Here’s a useful list of some of the best PayPal slot sites where you can use the popular e-wallet to claim a welcome bonus:
Best Mobile Slot Sites
With well over half of all UK players now preferring to bet on a phone, it’s essential that online slots are fully optimised for smartphones and tablets.
Thankfully, the majority work extremely well on smaller screens. However, a lot will depend on the technical specifications of what you’re using to play them on. Here are three of the best mobile casinos that have both Android and iOS apps to play slots:
Best New Slot Sites
It’s possible that you’ve already got an account and played at many of the top slot sites. With newcomers appearing regularly, trying a new slot site could be beneficial.
There are many advantages to playing at one of the latest UK casinos, including:
- Intuitive mobile apps
- Modern interface
- Vast number of slots
- New software providers
- Fairer bonus terms
- The newest games available to play
Here’s are three of the best new slot sites to consider signing up with:
Sites with Exclusive Slots
Offering exclusive games is a way for the best UK slot sites to stand out. But the exclusivity can differ in terms of timeframes and what’s available.
Here are three common types of exclusive slots that some leading casinos will offer their players:
- Early access to certain games before they’re released to other UK casinos.
- A provider who develops games for just one or a limited number of operators.
- A bespoke game variation such as a branded Megaways slot.
888casino is a prime example of a top slots site that offers plenty of exclusive titles. 888 has over 75 unique slots and games for players to pick from, which is one of the largest offerings on the market.
£88 No Deposit Bonus
18+ New players only • £88 is granted in FreePlay (FP) • FP must be claimed within 48 hrs of receiving the email and expires after 14 days • FP wins are credited as bonus and capped at £15, exc. JP win • Bonus wins are capped at £500 • Wager 30x bonus within 14 days • Wagering req's vary by game • Full T&Cs Apply. #ad
Demo Slot Sites
Plenty of UK casinos offer free online slots that enable players to test different titles before committing with their own funds. Some require a deposit before any can be played, but the majority simply require a successful registration.
Follow these simple steps to begin trying new games by using free demo slots:
If there aren’t any demo slots available for whatever reason, it’s worth considering a bonus from our list above. Promotional offers can often be used to try new titles without having to use real money of your own.
Tournaments are growing in popularity and are a carry-over from land casinos. Although the majority of events are open to anyone, some are exclusive to VIP members only.
The premise of each event is always the same – the person with the biggest balance wins after a predetermined amount of time.
But how do they work? Each one will be different depending on the operator. But generally, a specific game is chosen, and you may have to pay a small fee to enter, although free tournaments at slot sites are appearing more frequently.
Players then get to enjoy FreePlay slots with a certain number of credits. You’ll either have the chance to win a share of the prize pool or it’ll be a winner takes all scenario. Some UK slot sites have tournaments every 15 minutes, and others may offer them daily or hourly.
Best Online Slot Games Library
The best slot games are based on personal preference in reality. You may prefer Starburst whereas another player may prefer Gonzo’s Quest for example. A varied list of suppliers will give you a large choice of slots to play, and some will offer more than others.
The likes of Novibet and Videoslots both offer well over 3000 slots, which is an unrivalled amount. Some operators may list thousands, but the sign of a top casino is one that has the best slots in terms of RTP, popularity and bonus features. Some of the leading titles are listed below.
Another good indicator of a top slot site is the number of brand new titles they have listed. With over 100 released each month, the best operators will have games as soon as they’re released.
Finally, the best games library wouldn’t be complete without some of the leading progressive slots. Jackpots are important to many players. The likes of Mega Fortune and popular jackpot slot Mega Moolah both have top prizes that regularly reach millions of pounds.
How We Rate Slot Sites
Our experts have been reviewing and assessing casino operators for 10+ years. We go through the whole sign up process as a new player to understand exactly what areas they excel in and any areas for improvement.
Let’s explore the important aspects of what makes up a slot sites review.
With plenty of UK slots sites around, some are better than others in terms of the software providers they have available. Here are three of the best that stand out from the competition with the number of choices available from the leading suppliers:
The best online slots are all listed with these casinos. But it’s important to note that we don’t just rate the operators based on how many titles they have.
Here are some of the most popular software providers for slots at UK casinos.
Based in Sweden, NetEnt is one of the leaders in the industry when it comes to slots. Their innovative games with great graphics and appealing themes are what makes them stand out against the competition.
Some of their most popular slots include Starburst, Gonzo’s Quest, Jack and the Beanstalk, and Mega Fortune.
Microgaming has been producing some of the best slots since 1994. They boast a catalogue of well over 1000 titles the overall gameplay is great compared to some of the other leaders in the field.
Their top picks include top jackpot game Mega Moolah, Thunderstruck II, House of Fragons, and Immortal Romance.
Launched in 2007, Play’n GO is a Scandanavian brand that likes to produce slots with higher than average RTP percentages. Top titles you’ll come across at the best slot sites include Book of Dead, Vikings Go Wild, Riddle Reels, and Wizard of Gems.
With over 500 slots in their portfolio, Playtech is a popular choice for players who enjoy the TV show theme. They offer impressive Omnichannel products which allow slots like Age of the Gods to be played by many at the same time as part of their live casino package.
Some of the most popular Playtech slots include Buffalo Blitz, Age of the Gods, Monty Python’s Spamalot, and Pink Panther.
IGT is one of the veterans of the industry. Beginning life in the 80’s producing slots for land casinos, they’ve since made the switch to online gaming and have been creating innovative games for players for over 15 years.
Top slots from this provider include Cleopatra, Black Widow, Wheel of Fortune, and Da Vinci Diamonds.
Existing Promotions and Bonuses
As well as appealing welcome offers with fair terms, it’s important to keep existing players engaged with ongoing promotions. We analyse operators to find top slot sites that have a wide range of appealing benefits, including:
- Slot tournaments with cash prizes and free spins
- Prizes for topping a weekly or monthly leaderboard
- Free spins on games from particular slot providers
- Random cash drops on certain slots
- Free spins on new slots
Having these types of promotions and perks often separates the great casinos from the good ones.
Being able to choose from a number of payment options is important to any player. Debit card deposits are usually accepted, but it’s crucial for any top slot site to offer additional methods, especially mobile-friendly ones.
The most popular deposit and withdrawal options include:
- Debit cards
- Apple Pay
The best slot sites cater to those who bet on mobile, which is why you’ll see them offer the likes of Apple Pay and popular e-wallet MuchBetter.
It’s also important to keep an eye on the minimum deposit amount. Commonly, it’s set at £10, but there are some UK operators that have £5 or £20 as a minimum. The latter could put low stakes players off.
What sets many operators apart from the rest is the withdrawal times. The best will process payouts within hours or minutes, but there are some that take days.
On average, expect debit card transactions and bank transfers to take around three working days. E-wallet payouts take approximately 12-24 hours.
Generally, there are no extra costs involved, but players should consider any fees for depositing and withdrawing. Any additional charges will be clearly stated on the deposit screen, but the best slot sites won’t add any.
Reliable Customer Service
It’s often a prerequisite with players that casinos must offer 24/7 live chat. Any without support around the clock could discourage new customers from signing up.
It’s also important for operators to have a reliable support team in place. Not only to show trust, reliability and professionalism, but it also contributes to a site’s overall success.
There are numerous ways players can get in touch, including:
- Live chat – The favoured choice and the quickest way to contact support.
- FAQs – An in-depth section that’s easily accessible on the website will help to answer the most common queries.
- Phone – Although quite rare, a UK freephone number is preferable.
- Email – Operators will list an email address or include a contact form on the site for players to contact support.
- Social Media – More casinos are offering help via individual Facebook and Twitter accounts nowadays, which is useful for those looking for quick replies.
- Online Services – Skype and WhatsApp are used by some UK casinos.
- Call back – Even without a contact number, some sites offer a call back option for anyone who prefers to speak over the phone.
Live chat is the most popular option as it’s convenient and timely. Casinos will often email you a transcript of the chat too so that you can keep a record of the conversation.
The response times are just as important as the choice of options. If you’re waiting 20 minutes in a live chat queue, the customer service levels suddenly fall below your expectations. The best online slots sites will connect within a minute or two at peak times.
All casinos listed here hold a valid licence from the UK Gambling Commission (UKGC) and potentially others. This regulatory body ensures all operators follow the Licence conditions and codes of practice (LCCP).
Failing to adhere to the strict rules and regulations that have been set out could result in fines or even the suspension of a licence. The UKGC’s goals include:
Furthermore, any operators that hold the eCOGRA seal of approval demonstrate compliance to the highest standard.
This independent body ensures all games are random and fair. These are the places where you should be playing.
Make sure you read our trusted and unbiased reviews too. We’re honest with our views and we thoroughly review any newcomer. Rest assured you will always enjoy the top online slot sites in the safest possible environment.
Here are some of the leading UK slot sites that are approved by eCOGRA:
- 777 Casino
- Paddy Power
Website and App Features
The overall feel of a site and its mobile app is important to consider. How easy is it to navigate? Is there a native iOS and Android app available to download? Is it responsive? There are many questions that casinos need to answer positively, and the best slot sites excel in most areas.
Some of the leading UK operators will also have more than one app. For example, William Hill has a main casino app and separate ones for table games, slots, poker and bingo. This enables players to focus on their preferred type of game without having to spend time searching for what they need.
William Hill Casino
100% Buy-in Bonus
Opt in required • New customers to Casino page only • 1x per customer • Min. Buy in £10 • Bonus value 100% of Buy in • Max. Bonus £300 • 40x Wagering, Max Redeemable £4,000 • 50 Free Spins with x35 wagering will be awarded after the Buy in Bonus is completed • Max Redeemable £1,000 • Bonus expires after 7 days • Full T&Cs Apply. #ad
Regarding navigation, it’s essential that players are able to find their favourites with ease. This can be done with the use of filters. Not all casinos offer them, but filters simplify a player’s search.
An example of a top slot site with good filters is SlotsMillion. With a site that works seamlessly on desktop and mobile, the options players have available to them are arguably the best on the market. You can filter slots by:
- Type – Classic, new, video, 3D or jackpot slots.
- Software – Select a listed provider to show all of the games they have available.
- Features – Many options to choose from including free spins, special wilds, multipliers, and tumbling reels.
- Theme – Pick from the likes of Christmas slots, mythology, animal slots and much more.
- Paylines – Filter from 1-15, 16-25, 26-50 or 51+ ways to win
Many casinos don’t go into as much depth as SlotsMillion but having filters makes it easier for players to find what they need.
100% up to £20 & 100 spins
New customers only • Min deposit £10 • 40 spins upon first deposit • 2x30 spins 24 and 48 hours thereafter • Spins coin value: £0.01 • Winnings from spins are bonus funds • 48x wagering required for any bonus funds • Within 7 days for deposit bonus and 24h for winnings from spins • Max bet £3 • Game restrictions apply • Full T&Cs Apply. #ad
How to Find the Best Slot Sites
To get your casino journey off to the best possible beginning, it’s important to understand how to get started with the best online slot sites. Here’s our useful step-by-step guide to help you:
Pick a casino from our list of the best slot sites.
Browse our expert reviews that go deeper into everything a casino has to offer its customers.
Head to the casino of your choice by clicking through to their site.
Register with your chosen casino and complete any necessary ID verification checks.
Get the welcome bonus by following the on-screen instructions.
You may be required to deposit a minimum amount and enter a promo code to get the welcome offer.
Play slots to meet the wagering terms and try demo mode if it’s available.
Tips for Choosing the Best Online Slots Sites
To help you pick a UK slot site, here are a few helpful tips from our industry experts:
Knowing how online slots work before playing them is very important. It helps players understand the mechanics behind each one and how bonus rounds are triggered.
Always consider the following prior to betting on any:
- Payout rates
Payout rates and variance are two key factors that we’ll explain shortly but features, visuals, and the main theme are also important points of note.
You need to decide whether you prefer bonus rounds and extended game time or a simple spin of a reel. 3D graphics, dynamic sound, and HD video make for a great betting experience. Some themes are based on popular TV shows or video games, which might spike your interest.
Additionally, it’s always worth taking advantage of any slot sites that offer freeplay. This will allow you to test out each one without having to use any real money.
The best slots for winning have an RTP of 96%+. The exceptions here are jackpot slots as the prize is much bigger. They tend to sit at around the 93-94% mark.
This refers to a game’s frequency in producing winning combinations as well as the size of your potential wins.
If you’re playing a title where you don’t win too often but it has a larger prize, that’s a high variance game. If the slot you’re playing is spinning smaller winning combinations more often, then this is a low variance game. The best slots for winning more frequently are lower variance and popular with players.
What’s also important to understand is the range of special symbols. They include wilds, scatters, and multipliers. Let’s expand on each of these for you.
These are like jokers in a pack of cards. A wild symbol is essentially anything you want it to be in order to create a winning payline.
Wilds come in a few different shapes and sizes, including:
- Stacked Wilds – This is where the symbols appear on top of one another. It can form an entire section on a reel.
- Sticky Wilds – These remain on the screen and hold their position for a certain number of succeeding spins.
- Expanding Wilds – Every standard symbol of a particular type is substituted for a wild, which expands across the length of the reels. The number of winning combinations increases dramatically.
- Overlay Wilds – These variants stack up in a certain way at the end of a spin. They replace standard icons and help activate free slots spins or bonuses.
To unlock an exciting feature, three or more scatter symbols need to appear after a spin. They don’t have to be on the payline either, they can be anywhere on the reels.
Always check the paytable guides for each game. They will tell you how many need to show for an online slots bonus to materialise.
It does exactly what it says on the tin – multiplies your winnings. They’re very similar to scatters but with the added perk of increasing payouts. These range from 2x right up to 1000x and more!
One further benefit is that they multiply your total for the round and not just the payline it sits on. This type of symbol often appears when using free spins on slot site bonuses.
Most Popular Types of Online Slots
There are four main categories of online slots that you need to be aware of. They range from three-reel classics to progressive jackpots with exciting bonus rounds. Let’s break down each one.
Classic Three Line
Three-reel slots have been around for years. This old school classic is simple to understand. You just need to match three symbols on a single payline to win.
They don’t boast innovative bonus features or impressive graphics. But they’re still extremely popular at the leading UK slot sites. It proves that the charm of a game more than a century old still has a lot to offer.
Our experts have tested many of these games. Below we list highly rated 3-reel slots available online:
- Couch Potato
- Mega Joker
- Bermuda Triangle
- Funky Monkey
- Roman Riches
Modern slots have multiple paylines that give players more ways to win. The amount is typically around 20-25 lines. But some go as high as 100.
They offer a wider variety of themes compared to the classic single line equivalent. But please note, just because there are numerous winning combinations, it doesn’t necessarily mean your chances are enhanced.
It’s always worth checking the RTP (Return to Player) percentage of casino slots before you start betting. This is a good indicator of your winning probability.
Many of the most exciting games available at UK casinos come in the form of video slots. Players can expect the following benefits:
Software providers are constantly releasing innovative gameplay due to the lucrative bonus rounds, fantastic visual effects and higher payouts.
Megaways is growing in popularity all the time among new and experienced players. It was created by world-renowned developer Big Time Gaming back in 2015. They’ve since taken the casino slots world by storm.
In simple terms, it’s a random modifier that alters the number of symbols on every reel each spin. This means that there can be tens of thousands of ways to win. Some of the most popular Megaways slots available for you to enjoy include:
- Extra Chilli Megaways
- Holy Diver Megaways
- Primal Megaways
- Bonanza Megaways
Thanks to state-of-the-art technology and the creative minds of the game suppliers, the incredible graphics and imaginative storylines are only going to get better.
If you’re looking for something that gives players the possibility of winning millions, consider these online slots. With such a huge prize on offer, the odds are pretty low. But that’s where the game fairness at UK casinos comes into play.
Due to Random Number Generators (RNGs), most titles give everyone an even chance. However, progressives are slightly different. Your win probability depends on the provider.
Some of the most popular progressive jackpot slots include:
- Mega Moolah (Microgaming)
- Mega Fortune (NetEnt)
- Hall of Gods (NetEnt)
- Jackpot Giant (Playtech)
- Arabian Nights (NetEnt)
Best Online Slots in the UK
The best online slots in the UK are available at most sites. Experienced players have their tried and tested favourites. Some prefer games that have the best RTP, whereas others enjoy the bonus features.
Here’s a list of the most coveted titles that you can get stuck into straight away:
- Immortal Romance – A Microgaming classic with a vampire type theme. The RTP is just under 97% and there are four unique bonus rounds to enjoy.
- Book of Dead – An extremely popular title that’s been included in slots free spins UK bonuses for years. Explore an ancient Egyptian tomb Indiana Jones style.
- Starburst – Another game that features heavily in promotions at UK slot sites. A NetEnt creation with five reels, 20 paylines and stunning graphics.
- Gonzo’s Quest Megaways – Launched in July 2020, this title is already loved by many. There are up to 117,649 ways to win. Uncover avalanche multipliers, earthquakes and unbreakable wilds.
- Mega Moolah – Purple monkeys and beaming lions make this game exciting. These give you the chance to win big. There are four progressives jackpots to win on the wheel of fortune bonus game.
- Street Fighter II – One of the newer online slots. With a ton of features and retro graphics, it feels like the much-loved arcade classic. In terms of slots with bonus games, this is up there with the best.
- 1429 Unchartered – This title is packed with quality visuals and great features. It also comes with a superb RTP of 98.6%. With stacked wilds and free spins frequently awarded, it’s very popular among UK players.
- Jammin’ Jars – One of the most popular UK slots with an RTP of 96.83%. Players have a chance each spin to multiply their win by 20,000x.
- Bonanza Megaways – A six reel slot from Big Time Gaming that offers up to 117,649 winning combinations. It’s a top Megaways choice.
- Age of the Gods – A leading series of games that’s offered at most online slot sites by Playtech. Players can also play this slot with others in real-time at live casinos.
Slot Strategy and Tips
With so many slot sites offering strategies and ways to win, it’s tough to know where to turn. Our advice is to steer clear of anyone guaranteeing success for a price. Avoid scams like this.
Instead, heed the online slots tips provided by us. We cover this topic in great depth on a separate page. To give you a taster, here are a few worthwhile approaches to consider:
You should now be familiar with the best slot sites in the UK and how we rate them. Whether you prefer progressive jackpots or a classic three-reel version, operators will offer a plethora of different options.
Understand how to get started, explore the best online slots bonuses, and give FreePlay a go if you can.
What is the best slot site in the UK?
The best slots site is one that offers you a safe environment to bet and fair bonuses among other important factors. We’ve assessed the UK casinos to bring you the top 13 on our page.
Which online casino has the best RTP?
The top online slot sites for payouts are those that have slots with the highest Return to Player (RTP) percentages. For example, Goblin’s Cave has an RTP of 99.32% and Mega joker sits at 99%. Any casinos listing these should be considered.
The higher the figure, the more chance you have of winning over a prolonged period of time. However, always use these numbers as a rough indicator as they are calculated over hundreds of thousands of spins.
What are the best free online slots?
There are plenty of slot sites in the UK that offer FreePlay. Some of the best include Gonzo’s Quest, Cleopatra, and Rainbow Riches.
Please note that you must be registered and verified at the casino before you can access demo slots.
Which slot app is the best?
The top slots game apps in 2021 are those that offer safe and exciting gameplay in HD. William Hill is a top example of an operator with intuitive apps for each of their casino products.
Do slot sites offer slot bonuses?
Yes. Many of the best slot sites will offer free spins as part of a welcome bonus. Additionally, players can get numerous other promotions after the signup offer has been claimed.
What slot sites are there?
There are plenty of slot sites in the UK and some are better than others. On our page, we have a helpful step-by-step guide on how to find the best slot sites.
Are these slot sites safe?
All sites listed at Casino Deal are safe and hold a valid UK licence. Many go that one step further and display eCOGRA’s logo as a seal of approval. It proves that their game results are all random and fair.