Slot sites are among the most popular casino websites on the planet.
However, because there are so many top slot websites it can be tricky knowing which are the best ones for you to invest your time and money in.
That’s why OnlineCasinos.co.uk has reviewed all the UK’s best slot sites.
We’ve played the games, checked the bonuses, found out what the payouts are, and assessed all the other things that you care about.
All you need to do is read through our guide, decide what the best casinos are for you, then head over to the websites and play their great slot games.
10 best slot sites
PlayOJO
Mr Green
bgo
LeoVegas
Grand Ivy
888
Playzee
The Sun Vegas
Dream Vegas
Betway
Top slot sites reviewed by OnlineCasinos.co.uk
- PlayOJO
- Mr Green
- Dream Vegas
- LeoVegas
- Grand Ivy
- 888
- Playzee
- The Sun Vegas
- Jackpot247
- Betway
- Mansion
- Casimba
- All British
- GentingBet
- Roxy Palace
- Gala
- 32Red
- Grosvenor
- Bet365
- Casino.com
- bgo
OnlineCasinos.co.uk’s expert thoughts on the 10 best slot sites
PlayOJO: king of the UK’s slot sites
Mr Green: huge collection of slots games
bgo: great free spins offer
LeoVegas: combination of great payouts & lots of games
Grand Ivy: excellent variety of video slots
888: trustworthy slot site
Playzee: outstanding loyalty programme
The Sun Vegas: exceptional new slot site
Dream Vegas: ace mix of new & classic slots
Betway: ace slots games & lots more
Gold medalist 🥇 PlayOJO: UK’s best slot site
Credit: PlayOJO Casino
OnlineCasinos.co.uk slot sites rating ⭐⭐⭐⭐⭐
PlayOJO Casino is number one when it comes to the UK’s best slot sites.
It has the most games, lowest wagering requirements for its bonuses, and one of the finest apps of any casino. It’s perfect for people who love to play the slots.
Top 3 features of PlayOJO Casino:
Close to 3,000 slots titles 🎰
No wagering requirements 💷
Lots of jackpot games 🤑
Credit: PlayOJO Casino
Slots bonus package ⭐⭐⭐⭐: 50 free spins 🎰
The website is also incredibly user friendly. Indeed, you really feel like PlayOJO pulls out all the stops to make sure its new and returning players have the best time when they try their hand at its many brilliant games.
Vist PlayOJO Casino now to find out why it’s at the top of our list of the best slot sites.
Bonus offer terms and conditions
First-time depositors only. Min. deposit £10.
Maximum amount of Free Spins is 50.
Game: Book of Dead - Spin Value: £0.10 each.
Excluding new players in Northern Ireland.
OJO's Reward and Game Play Policy Applies. Read now.
18+
Silver medalist 🥈Mr Green: huge collection of slots games
Credit: Mr Green Casino
OnlineCasinos.co.uk slot sites rating ⭐⭐⭐⭐⭐
Mr Green has an incredible selection of games that make it the envy of most slot sites.
It features a vast array of slots. Vegas slots, jackpots, instant wins, interactive titles, and retro options are among the many games that you can play.
Top 3 features of Mr Green Casino:
Diverse collection of slots games 🎰
Real Thrill slots bonus competitions 💷
Great blog with helpful gaming tips 📚
Credit: Mr Green Casino
Slots bonus package ⭐⭐⭐: 50 free spins 🎰
Perhaps the best thing about Mr Green is the exclusive games it offers. The site has some exceptional titles that are regularly updated and offer a gaming experience you don’t get from any other casino.
Head over to Mr Green Casino now and start using one of the best casino sites in the world.
Bonus offer terms and conditions
When you stake £20
Opt in required per day. 1x per customer per day. Min. £20 must be staked on Starburst™. Free spins on Starburst™ only. Max. 5 free spins at £0.10/spin with 35x wagering. Bonus expires 24 hours after issue. Game weighting, game, country, currency, player restrictions and terms apply.
Bronze medalist 🥉 bgo: great free spins offer
Credit: bgo Casino
OnlineCasinos.co.uk slot sites rating ⭐⭐⭐⭐⭐
bgo Casino has one of the best free spins offers of all the slot sites we’ve reviewed.
The casino gives you the chance to win up to 500 free spins once you sign up for an account. You need to deposit a minimum of £10 to be eligible for the offer and then take on the site’s Mega Wheel.
Top 3 features of bgo Casino:
Daily slots tournaments 💷
Good selection of new slots games 🎰
Weekly rewards hub 💸
Credit: bgo Casino
Slots bonus package ⭐⭐⭐⭐⭐: 500 free spins 🎰
bgo Casino’s tournaments are one of the things that really sets it apart from the other casino sites. It holds 12 each and every week, giving you the opportunity to battle against other players to win rewards.
Check out bgo Casino now and see for yourself why it’s one of the top slot sites in the UK.
Bonus offer terms and conditions
UK only. win up to 500 free spins from mega wheel on 1st deposit. 24-hour expiry. Max bet £2.50, max spins win £8 per 10 spins, max bonus win £150, selected games & 65x wagering on winnings. No neteller/skrill. full T&Cs apply.
LeoVegas: combination of great payouts & lots of games
Credit: LeoVegas
None of the other slot sites we’ve assed match LeoVegas Casino for the combination of games and the level of payout offered to gamblers.
It features over 600 games and has an RTP of 97.60%, making it not only a fun website but one where you could earn some cash.
This means that LeoVegas is the best option for casual betters who play for fun and more serious gamblers who want to win some money.
Grand Ivy: excellent variety of video slots
Credit: The Grand Ivy Casino
If video slots are what you look for in your slot sites then Grand Ivy Casino is perfect.
Grand Ivy Casino has a superb range of games and its site makes it easy for you to find the ones you want. It does this by letting you filter by the software provider or name of the game.
So, if you’re a fan of video slots then pay a visit to The Grand Ivy Casino today.
888: trustworthy slot site
Credit: 888 Casino
888 Casino is a slot site that’s reliable, trustworthy, and safe.
You can be sure you’re safe when you play slots at 888 Casino because it was voted the Best Casino Operator at the 2020 Gaming Intelligence Awards and 2019 EGR Awards London.
These are awards that only truly secure casinos can win.
Try the 888 Casino website now to see with your own eyes just how trustworthy it is.
Playzee: outstanding loyalty programme
Credit: Playzee Casino
Playzee Casino is a slot site that really looks after its loyal players.
It rewards its returning players with the Zee Club, a scheme that gives perks like unique bonuses and free spins.
You become a member of Playzee Casino’s loyalty program as soon as you create an account. You then work your way up the ranks as you play your favourite games.
See what Playzee Casino has to offer to learn if it can become one of your top slot sites.
The Sun Vegas: exceptional new slot site
Credit: The Sun Vegas Casino
The Sun Vegas Casino is one of the best new slot sites you can use in the UK.
You can pick from over 600 brilliant slots to play and if you do decide you fancy a change then you’ll adore the site’s incredible 3D roulette offering.
Follow the link to The Sun Vegas Casino to learn why few slot sites can compete with it.
Dream Vegas: ace mix of new & classic slots
Credit: Dream Vegas Casino
Dream Vegas Casino is a slot site that is ideal for all types of slot fan, with its superb mix of retro games and new titles.
Starburst and Book of Dead are among the classic slots games you can try, while Saxon and Blinged are some of the finest new titles you’ll find at any casino.
Make your way to Dream Vegas Casino now to experience a slots site that gets its games catalogue spot on.
Betway: ace slots games & lots more
Credit: Betway Casino
Betway Casino is one of the slot sites that goes beyond fruities and jackpots.
Not only does it feature some brilliant slots titles, but it also has an exceptional poker offering (including a cardroom), great live gaming, and outstanding sports betting options.
If you want a slots site that offers a bit more then try Betway Casino now.
3 top slot sites for free spins
Slot Site | Free Spins Rating |
bgo | ⭐⭐⭐⭐⭐ |
LeoVegas | ⭐⭐⭐⭐ |
PlayOJO | ⭐⭐⭐⭐ |
Every slots site worth its salt will offer free spins and we found some great offers when comparing the very best sites.
However, there was a clear winner: bgo Casino.
Credit: bgo Casino
You can earn up to 5x the amount of the next highest casinos, putting it streets ahead of the competition.
The catch is that you have to earn these spins by competing against the site’s Mega Wheel, so the amount you get depends on how well you play.
An honourable mention goes to PlayOJO. This is because the free spins you get from the site come without wagering requirements. This means you don’t need to invest your own money to get the full benefits of the offer.
Slot site with the best free spins offer: bgo
Credit: bgo Casino
You can earn up to 500 free spins at bgo
Bonus offer terms and conditions
UK only. win up to 500 free spins from mega wheel on 1st deposit. 24-hour expiry. Max bet £2.50, max spins win £8 per 10 spins, max bonus win £150, selected games & 65x wagering on winnings. No neteller/skrill. full T&Cs apply
3 top slot sites for free spins games
Slot Site | Games | OnlineCasinos.co.uk Rating |
PlayOJO | 2800 | ⭐⭐⭐⭐⭐ |
Mr Green | 1694 | ⭐⭐⭐⭐⭐ |
bgo | 1093 | ⭐⭐⭐⭐⭐ |
Games are one of the main reasons to head to a slot site – sure, you want to win some money but you need to place a bet on a game to do so.
Because there are so many slot titles out there, we think it’s crucial to compare how many games are offered by the leading slots sites.
And which site has the most? PlayOJO Casino, with an enormous 2800.
Credit: PlayOJO Casino
PlayOJO Casino’s huge games category puts it more than 1300 games ahead of second-placed Mr Green.
This means that it was a no-brainer to pick PlayOJO as being the best slot site for games.
Slot site with the most games: PlayOJO
Credit: PlayOJO Casino
PlayOJO Casino has around 2800 slot games
3 top slot sites for payout
Slot Site | Games | OnlineCasinos.co.uk Rating |
Mr Green | 99.90% | ⭐⭐⭐⭐⭐ |
Betway | 98.10% | ⭐⭐⭐⭐⭐ |
bgo | 98.00% | ⭐⭐⭐⭐⭐ |
First and foremost, playing slot games should be about one thing – having fun.
Slot games are like every other game, you play them to be entertained and your enjoyment should begin with simply participating.
However, like every other game, slot games do have an objective – to win. And the reward you get for winning slot games is money – your payout.
Payouts for slot games are measured in RTP and Mr Green is the site that offers the most attractive figure, with a high-end RTP of 99.90%.
Slot site with the highest payout: Mr Green
Credit: Mr Green Casino
Mr Green Casino has a high-end RTP of 99.90% for its slot games
Most popular slot games you can play
Credit: Wikimedia
Games are the key to the best slots sites. They’re the reason you visit them, the things that bring you fun from your gambling sessions, and the way you can win some cash.
The top websites offer hundreds, even thousands of slot games, and this makes it tricky to know what the best ones are.
That’s why we’ve highlighted the five most popular slot games you can play.
Our 5 most popular slot games
Starburst
Leprechaun Hills
Centurion Free Spins
Game of Thrones
Casper’s Mystery Mirror
Starburst
Credit: YouTube
Payout: 96.10%
Paylines: 10
Jackpot: 250
Software provider: NetEnt
Leprechaun Hills
Credit: YouTube
Payout: 96.47%
Paylines: 40
Jackpot: 6
Software provider: Quickspin
Centurion Free Spins
Credit: YouTube
Payout: 95.00%
Paylines: 20
Jackpot: 500
Software provider: Inspired
Game of Thrones
Credit: YouTube
Payout: 94.86
Paylines: 243
Jackpot: 30
Software provider: Microgaming
Casper’s Mystery Mirror
Credit: YouTube
Payout: 95.50%
Paylines: 40
Jackpot: 500
Software provider: Blueprint Gaming
Why free spins are key to the top slot sites
Credit: Wikipedia
Free spins are great for new gamblers who are deciding what slot sites they want to sign up to – they give you a chance to try out games without paying a penny.
While free spins might sound like a great deal (and in many ways they are) they do come with some conditions that you need to be aware of:
Free spins are generally for specific slots games
Free spins can be dished out in daily doses – not all at once
Free spins often have a time limit on them
And the thing to note is that free spins only apply to new gamblers. This means that if you’ve already signed up to a slots site you are no longer eligible to get its free spins offer.
What is RTP & how does it work for slot games?
Credit: Flickr
It’s important to think about the payouts you're getting from the casino sites you bet at.
This is because it’s not a lot of fun if you don’t win the games you play and having fun should always be the priority when you’re playing the slots.
How do you measure the payout in slots? By the RTP (return to player). Here’s an example of how that works:
If a slot site has an RTP of 99.99%, this means that £99.99 of every £100 wagered is returned to players in the long run.
But, continuing with the example, what you need to know about RTP is that just because you spend £100 it doesn’t mean that you’ll get £99.99 back.
This is because the RTP of a slot site covers every player and every bet placed – and some bets win and some lose.
Top slot sites for mobile gambling
Credit: Pexels
Mobile gambling is something that gamblers expect from slot sites – with more internet traffic coming via mobile than desktop, gambling websites need to have a mobile offering to be truly online.
Unsurprisingly, pretty much every slot site we compared has an app.
The apps created by slot sites replicate their website offering as closely as possible, with many being a mirror version of the site – for example, the number of games is often near-identical when comparing the app and website.
Credit: Pixabay
Because the mobile and online offering is so similar, this means the apps of slot sites must be judged on something different – how easy they are to use.
Many of the slot sites we reviewed have apps that are a breeze to use, honourable mentions going to:
LeoVegas
32Red
Mr Green
Betway
PlayOJO
Of these, one slot site stood out above the rest: PlayOJO Casino.
We think that PlayOJO Casino has the best app of all the slot sites we compared, but that’s not the only reason we think it’s great for gamblers – it also has some great roulette, poker, blackjack, and (of course) slot games.
You can learn about all the reasons we think it’s a top slot site by reading our full review of PlayOJO Casino.
How OnlineCasinos.co.uk reviews the best slot sites
Credit: Pikist
OnlineCasinos.co.uk is a team of gambling enthusiasts who love to play casino games.
This means that we want the same things that you do from the slot sites we bet at:
Great games
Real bonuses
Competitive payouts
Safe and user-friendly site
Brilliant app
We begin by looking for gambling regulatory icons on websites, so that we know that the site can be trusted to look after your sensitive data.
Once we know a site is trustworthy, we check to see how many games you can play on both the website and app. And we play the games too, so that we can be sure that you’ll get a great experience from the slot sites we’ve recommended.
We’re very proud of our review process. Not just because we spend huge amounts of time testing the casinos and detailing our thoughts, but because we know that we’re recommending great slot sites to our fellow players – that’s you.
What are the different sort of slots that I can play?
Credit: Pikrepo
The top slot sites have hundreds, even thousands of different games you can play.
Video and retro slots are often the most popular slot titles at these sites. However, they aren’t the only options available to you because there’s a selection of different slots you can play.
These are the key slots you can choose:
Progressive jackpot slots
Credit: PlayOJO Casino
Progressive slots increase in value each time you wager some money on them. This means that you have the potential to really boost your winnings.
One thing to note about progressive slots is that they’re often highly volatile.
So, while you can earn larger wins from these games, you can find that you need to make lots of bets before getting close to the jackpot.
Real money slots
Credit: LeoVegas Casino
Real money slots are games that you play for your own money, they’re the ones that give you a chance to earn some actual cash.
Because you’re investing your own cash on these games you’ll need to manage your bankroll carefully, to make sure you don’t spend more than you can afford to.
It’s a great idea to set a limit before you play. That way you know exactly what your limits are and it's easier to stick to them.
Free slots
Credit: Mr Green Casino
Free slots are games you can play without spending any money, making them ideal for testing your skills before wagering your cash.
Many slot sites offer free versions of their real money slot games.
While each casino is different, you’ll often find the free version of the game advertised next to the real money one – there will generally be a button that says something like “play for free”.
Retro slots
Credit: bgo Casino
Retro slots are the classic games you’ll find at casinos.
You’ll be able to spot these slots because they are designed to look like the classic fruity machine games that are used in land casinos.
Retro slots also generally use three or five reels and one payline. This makes them simpler to play and means that they’re ideal for new players.
Video slots
Credit: The Sun Vegas Casino
Video slots are the most popular games you’ll find at most casinos, particularly ones that specialise in slots.
Video slots are incredibly varied, offering a range of reels and paylines, along with a broad range of themes.
Some of the themes you can expect to find include films and TV shows, games, and fantasy.
What are the best slot games providers?
Credit: Max Pixel
The best slot sites feature games from a huge range of providers, with some of these casinos using over 30 different software companies to supply their slots titles.
While there are many great providers, there are a few industry leaders you should look for.
3 top slot game providers
Playtech
Microgaming
NetEnt
We’ve assessed each of these great slots games providers in our casino software review.
It lists some of the top games made by each of these companies, so you can get some tips before you visit your favourite slot sites.
How can I find a safe slot site?
Credit: PeakPX
The first thing any gambler should expect from the top slot sites is that they are able to have fun. The next thing they demand is that the site is safe.
You can confirm that you’re gambling at a safe website by looking for the icons of licensing and legislation organisations.
Any slot site that operates in the UK has to be regulated by certain gambling organisations and national authorities, even those that are registered outside of the UK – like in Sweden, Malta, or Gibraltar.
Slot sites want their players to know that they’re safe to use and the way they confirm this is by putting the icons of gambling regulators on their websites. There are some key icons you need to look for and these are the most important ones.
Gambling organisation icons to look for at slot sites
UK Gambling Commission
Credit: Gambling Commission
Any slot site that is allowed to operate in the UK is ultimately regulated by the UK gambling commission.
Government of Gibraltar
Credit: Wikipedia
If a slot site is licensed in Gibraltar then you’ll know this to be the case by the Government of Gibraltar logo on its website.
Malta Gaming Authority
Credit: Malta Gaming Authority
If a slot site is licensed in Malta somewhere on its website you’ll be able to find the logo of the Malta Gaming Authority.
Spelinspektionen
Credit: Spelinspektionen
You’ll know if a slot site is licensed (or able to operate) in Sweden because the Spelinspektionen logo will be displayed on its website.
Responsible gambling icons to look for at slot sites
We’ve been clear that fun is the main reason you should gamble and you should never lose sight of this, rather than focussing on whether you win or lose – even the best gamblers can lose and even the worst ones can win.
How you measure fun is up to you.
You might decide that fun looks like lots of brightly coloured slots, or you might decide that it looks like a slot game with a competitive RTP. But the key is that you gamble responsibly.
Slot sites want their gamblers to know that they have a commitment to responsible gambling and they do this by putting the icons of relevant organisations on their websites.
These are the responsible gambling icons you should look out for on slot sites:
GamCare
Credit: GamCare
GamCare is a UK charity that offers support to people who believe they have a problem with gambling. It’s an organisation that people can speak to and seek the support that they need.
GAMSTOP
Credit: GAMSTOP
GAMSTOP is a self-exclusion organisation that allows gamblers to block themselves from slot sites and other betting websites.
People can contact GAMSTOP and register their intent to self-exclude from a specific site for a set amount of time. This means that during this timespan the person will be blocked from using that site by the site itself – it’s like they have a temporary ban.
You can contact GAMSTOP to find out if your preferred slot sites offer self-exclusion.