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Best Casino Slot Machines to Play

Starburst Slot

Online casino games are super popular across the UK with their fast entertainment and gameplay and the chance you get to win some amazing prizes. There’s such a choice today. From your classic 3 reel and 5-reel slots to 3D slots and progressive jackpot games.

When it comes to assessing the best casino slot machines to play, it does depend a little on your preferences in terms of what types of slots you want to play. Whether you rate bonus features, yearn for jackpot wins, or insist on good mobile friendliness or a combination of these factors in varying degrees, this blog considers best UK online slots by RTP, payout, bonus games, best casino sites and mobile usage. So let’s dig deep into those factors now.

Rainbow Riches 


Having a good RTP or ‘return to player’ rate relates to when players get paid and is calculated as a percentage. The % RTP is the expected wager percentage a game will return to player in the long run. This refers to averages. Some will bag big wins, others won’t. Progressive pots give hefty prize payouts but pay out way less frequently, other sites have smaller payouts but more frequently.

While best casino slots on huge RTPs include Monopoly Big Event (RTP 99%) due to its increased multipliers and guaranteed win spins and Rainbow Riches Drops of Gold with its high 97.75% RTP (available when players use the Big Bet feature giving players 5 linked accumulative spins with an upgraded ‘Super Rainbow’) - don’t be put off by lower RTP levels for progressive jackpots.

Starburst has an RTP of 96.10% with low volatility but comes with chances of winning up to 500x your stake with its 5 reel 10 payline structure and wilds, joined by some other high RTP scorers like Blood Suckers (98%), Mega Joker (99%) and Chilli Heat (96.50%). MRQ, Merkur and 888 Casino are among those modern casino slot sites with the highest RTP games.

Chillie Heat Slot

In general look for an 95% RTP or higher, however progressive jackpot slots with lower RTP doesn’t translate into lower profitability. Some examples are in the table below which include some of the top progressive jackpot sites in the world that have RTP percentages in their high eighties. ‘Good’ RTP differs depending on type of casino game you’re playing - and progressive jackpots are the exception to the rule.

Mega Joker 

99% RTP

Jackpot 6000 

95% RTP

Mega Moolah

88.12% RTP

Major Millions

89.37 RTP

1429 Unchartered Seas

98.5% RTP

* All values are subject to change at any time.


At the end of the day, slots that pay out generously is a good place to start when ranking best casino slot machines to play. It’s nice to fill pockets and purses after a flutter on a casino site but there is never any guarantee. In terms of looking at best casino slots with high payouts, there are many that attract thousands of players at a time with alluring jackpots. Top paying jackpot wins can be found in games like Mega Moolah Mega also known as the Million Maker, Mega Fortune Mega, WowPot Mega and Jackpot Giant where wins can go as high as nearly 19 million euros (many of the top ones have been on Mega Moolah Mega).

Interestingly, one of the biggest winners recorded was playing on a mobile phone at the time. Top recorded wins range from 11m up to 19m euros. Big payers often listed in reviews are Mega Fortune (NetEnt) with an £18m win in 2013. Mega Moolah (Microgaming) - 8m euros, Hall of Gods (NetEnt), 6.7 million euros and Arabian Nights (NetEnt) with its 2.6m euro prize and Gladiator 2 million euros prize.

Another consideration on best payout slots are newer jackpot slots on the scene. Fresh titles that payout well to consider spinning on include Temujin Treasures, a Mongolian-themed Pragmatic Play video slot rewarding you with 4 jackpots total, worth up to 888x your stake and a high payout rate of 96.55%. Kingdoms Rise Battle Beast, a fantasy Playtech game with 4,096 betways and three large jackpots worth 10,000x your stake. Also, El Dorado Infinity Reels, with its Mayan-theme, by Yggdrasil with a top jackpot that adds a multiplier of 888x.


You should always go for a casino with a good reward system, for example, welcome bonuses, cash to recoup losses and free spins at high paying jackpot slots. Weigh up payouts against ability to set risk levels. Progressive slots with high volatility mean less frequent payouts with higher stakes, lower risk brings frequent smaller payouts.

Bonuses can be looked at in terms of VIP perks too. Some casinos reward players as they play which ups wins. Weigh up RTP against bonus features of games. Another key factor is to check terms and conditions of paying out on bonuses. Often the wagering requirements are high, and this makes a difference on playthrough on wins so check terms always and look for site trustworthiness. Many casino sites offer great welcome bonuses for example.

Some of the most popular games are popular for their bonus rounds. Such as, Cleopatra (IGT) where players can trigger a free spins bonus round with 15 free spins up for grabs with a 3x multiplier – simplistic but a good payout! Zeus (WMS Gaming) has potential wins from free spins that make it super popular. Buffalo (Aristocrat) has a bonus round where you get free spins with a twist where you can land a mega multiplier of up to 27x. Beverly Hillbillies (IGT) gives a bonus round called The Millionaire Mile some say the most exciting ever released, where the player spins the ticker to navigate round the trail to try to win as much cash as possible. Another worth a mention is The Walking Dead (Aristocrat) with extra wheels giving it depth. Elvis the King (IGT) has lots of free spins. Rainbow Riches; a pots of gold bonus, road to riches bonus and wishing well bonus, all super popular.


What are the best casino slot machines when it comes to playing on your smartphone? Games need to be well designed and fun to play on your mobile phone when you are on the go. They should be easy to play and great to look at, have good usability and be great eye candy. There are many casino sites offering responsive games that work well on mobile, where no app is required. In fact, most of the newer casino slots are responsive to mobile. Older games may not be.

There are even sites that focus on mobile and make it easier than other sites to load up cash and withdraw using phone pay features. Such sites include ‘Pay By Mobile Casino’ which does what it says on the tin – allowing you to play 1000+ games on your phone (and desktop) this suits many players on the go today.


There are several things to look for when it comes to assessing best casino slot sites, it does kind of depend on what you are looking for in a casino slot game though. Some people like table games with a real dealer as well as slots and some like pure slots sites. Fast payout sites include MrQ, most popular Merkur Slots and 888 Casino and many more. The best thing is to decide what it is you like most in a slots game and then go from there. Choose one that is highly rated and holds licenses by regulated well known bodies such as the UK Gambling Commission. Also check things like minimum deposits and withdrawal rules, wagering requirements and game categories on offer. Another factor to consider when looking at casino slot sites is customer support quality. Always check the terms and conditions before playing any of the games.


When it comes to assessing the best casino slot machines to play today, it really does depend on what you are looking for in a casino slot. At the end of the day, slots that pay out generously is a good place to start when ranking best casino slot machines to play but there are also other considerations that are important too like RTP, bonus features and mobile usage.

Whether it is payout (something like Mega Moolah being the king on payout), high RTP (e.g., Monopoly Big Event) ‘on the go’ convenience (e.g., Pay By Mobile) or bonuses (e.g. Cleopatra, Zeus), hopefully this blog has helped you consider some of the key factors that go some way towards being a good yardstick with which to measure your casino slot machine games against. Remember to check terms and licenses and things like deposit and withdrawal rules and when you are sure of those - there’s a lot of variety, you won’t be spoilt for choice. Why not check out some of the great games at Kong Casino while you are at it?

*All values (Bet Levels, Maximum Wins etc.) mentioned in relation to this slot game are subject to change at any time.