What are the videoslots with the biggest Jackpots? There is constant competition between the big casinos and developers to establish new and successful videoslots. This leads to constant improvements and new products flooding the market. There are a few large parties who can be considered the top of the line though.

Mega Moolah

This game was mentioned once before, as they broke a world record in 2021 with a jackpot of over 19.4 million euros. They held two previous records as well, with a jackpot of 17.88 million euros in 2015 and 18.9 million euros in 2018. As such it is one of the only videoslots to claim a spot in the Guinness Book of World Records. These achievements have given the game a massive amount of publicity, which is why the game is currently the most profitable slot machine on the market.

Mega Moolah was first released in 2006 by MicroGaming, with the game receiving regular updates ever since. The theme of the game is centred around a safari trip on the African savannah, with the player spotting many wild animals while spinning the slots on a 5 by 3-reel grid. The animals have also been added as symbols on the reels as symbols for the higher prices. The rest of the symbols were taken from the well-established deck of cards.

The game has a payout percentage of 96,98%, with a minimum of € 0,01 required to spin. The large jackpot combined with such a small starting sum makes Mega Moolah one of the most attractive slot games on the market.

Immortal romance

This game is another popular game developed by MicroGaming. Immortal Romance was released in 2012, though its age is not immediately apparent from its appearance. The theme of the game is loosely inspired by vampire romance stories, such as the popular Twilight series or True Blood. The game even has an actual storyline following four vampire characters on their search for romantic relationships, with these characters appearing on the reels as premium symbols. Some other medium symbols are set pieces and objects from the story, while the standard symbols follow the deck of cards.

The maximum payout is 3.635.000 coins, with there being a total of 243 combinations that result in the player receiving a payout. The minimum required to spin is € 0,30. The large jackpot combined with the many different winning slot combinations makes immortal romance a very attractive game to play.

Hall of Gods Mega

The Hall of Gods slot has been online since it was first released by Netent in 2011. While its age might be apparent, this does not take away from the enjoyment. This game is enjoyed all over the world but is especially popular among Norwegian players. Part of this might be the theming, which is centred around some of the more well-known Norse gods.  As such, the main roles are played by Odin, Thor, Loki, Idunn, and Freya. Most of the jackpots have been paid out to Norse players as well, with the largest up to this point being €7.820.888.

The payout percentage of the game is 96,5%. The number of slot combinations that result in a win is relatively small, with only 20 lines resulting in a payout for the player. The jackpot in Hall of Gods is not singular however, with there being three jackpots building up simultaneously. This means the jackpot falls roughly three times as often in comparison to a similar game with a singular jackpot.

Book of Atem

Another successful game from the developers at MicroGaming, this game distinguishes itself by the usage of the wowpot jackpot system. The jackpots are regularly lower than those of singular progressive jackpots, but that does not mean they are insignificant. The wowpot system distinguishes itself by the fact that it technically consists of four jackpots. These are the following:

The Wowpot jackpot

This is the main jackpot. The payout starts at a minimum of 2 million euros and rises from there. The edge this jackpot has over most games with singular jackpots is that the minimum payout price is higher. For example, Mega Moolah puts its minimum payout at 1 million, only half of a wowpot jackpot. While the maximum payout of Mega Moolah is higher, Book of Atem has more consistently high payouts. The record payout for Book of Atem so far was in April of 2021, when a man from England received a payout of € 17,5 million.

The major jackpot

This jackpot has a minimum payout of € 50.000.

The minor jackpot

This jackpot has a minimum payout of € 100.

The mini jackpot

This jackpot has a minimum payout of € 10.

The one downside of Book of Atem is that the payout percentage has been lowered to compensate for the relatively generous rules of the Wowpot jackpot. As such this has been lowered to 93,5%. This percentage is still not exactly low, but many online slots do have a higher percentage.

Jackpot Giant

This game was developed by Playtech and is their largest progressive jackpot. This game is most interesting once the jackpot has risen into the millions. The game puts the jackpot at a minimum of € 100.000, which means it may take some time for the jackpot to rise to this level. That does not mean it does not happen though, as a British player won € 5.6 million in 2016.

One downside of Jackpot Giant is that the jackpot is only available to win when a player bets the maximum amount of € 4. If they play with less, they can only win through the premium and wild symbols, which gives a payout of between € 500 and € 4000.

Beach life

Beach life is another game from Playtech with a large payout. It is in many ways quite alike to Jackpot Giant. The jackpot is only available to win when a player bets the maximum available amount of € 10. The reason for this is that the game allows the player to decide how many lines they play with. The jackpot is only available on the 20th line, which only appears when a player bets € 10.

The record for this jackpot is € 6.2 million, which was hit in 2012 at Betfred Casino. This game may have been overtaken by bigger players but is still a very solid option if the jackpot has been built up.

TNT Tumble Dream Drop

This game is one of the more recent additions in the Dream Drop series of videoslots by Relax Gaming. It has a wide betting range, from only €0,20 to a maximum of €100 for a single round. The game has five progressive jackpots, which are as follows:

  • Rapid, starting at €1.
  • Midi, starting at €5.
  • Maxi, starting at €100
  • Major, starting at €25.000
  • Mega, this is the highest with a minimum of €500.000.

Aside from the jackpots, players can win a maximum of 10.000 times their betting amount. The payout percentage is relatively low at 94%, which is on the lower end for videoslots. The many different ways to win a payout and the flexible betting amount mitigate this percentage, however.

Panda´s fortune

This panda-themed game was developed by Pragmatic Play and released in 2017. The game has a Chinese theme with a focus on pandas, as they are considered a symbol of luck in many areas of China.

The game has three jackpots with payouts depending on the total betting amount of the player. The highest of these has a payout of 800 times the betting amount. With a maximum betting amount of €125, this payout can reach as high as €100.000. The payout percentage itself is quite high, at 96,17%.

King Cashalot

One of the older titles released by MicroGaming, first seeing release in 2004. As the name indicated, the theme of the machine is centred around Camelot and King Arthur. Though games like Mega Moolah have somewhat overshadowed King Cashalot, it is still a very solid game.

The payout percentage is a reflection of its time, as this lies at a relatively low 90,45%.  Despite this low percentage, there have been payouts in the millions. One player in 2011 walked away with a payout of € 1.527.228. The max betting amount is still relatively low compared to many more recently released games, as it sits at € 2.25 for a single round. The minimum is € 0.09, which means the barrier of entry is relatively low.

Mega Fortune

Mega Fortune is one of the biggest games made by developer NetEnt. The highest recorded payout went to an anonymous Finnish player in 2013, who received a payout of € 17.860.868. This payout remained the world record for three years, before being dethroned by Mega Moolah.

The payout percentage lies at a generous 96,6%, which enables winners to walk away with a payout of around € 4 million on average. The jackpot drops on average every ten weeks. This means around 5 people a year become millionaires due to Mega Fortune.

Temple Tumble 2

This is the sequel to the original Temple Tumble by Relax Gaming, which brings numerous improvements. One of these new developments is the five progressive jackpots that can be won. As a predecessor to the rest of the Dream Drop series, this game follows the same jackpots as the others, ranging in scale from rapid to mega. There are 46.656 different ways to win a payout, with the betting amount ranging from € 0,20 to € 100. Players can win up to 10.045 times their betting amount, which makes this game attractive even without the multiple progressive jackpots. 

The legal arrangements between the developer and the website regarding Jackpots

Jackpot payout

It would be logical to assume that a win for a player is a loss for a casino. Many operators are still able to pay a progressive jackpot in the millions. Most businesses would not be able to suddenly deduct millions from their budget. Casinos do not experience a jackpot payout as the massive burden it might seem, however. The reason for this is that casinos usually do not bear the burden of the jackpot. The operator contributes to the initial seed value, but the rest of the funds are all contributions from the players. They will usually divide the amounts paid by the players between the different jackpots they operate as well as the casino itself. 20% might be divided over these jackpots, with 80% being taken by the casino itself.

Operator or developer

Operators will usually pay out the jackpot, though this burden can also fall on the developers of the game. The reason for this is that progressive jackpots can be divided into two categories.

Global jackpot

The global jackpot, also sometimes referred to as the network jackpot, is not bound to a single casino. It is instead bound by the type of game. This means that all games of the same type are connected through a network. The jackpot in this case is not collected by the casino, but by the developer. Developers will usually keep this jackpot in a separate financial account for security reasons. Since the developers are the one who collects the jackpot, they are also the ones responsible for the payout. They can pay the player directly by transferring the money to their personal account or transfer it to the casino account to be withdrawn at a later moment. The global jackpot system allows jackpots to grow rapidly to enormous sizes. The current world record for the largest jackpot payout was a global jackpot, and was set in 2021 by Mega Moolah, with the payout being over €19.4 million.

Local jackpot

The local jackpot grows within a single casino. These jackpots will usually be lower as a result. The casino themselves collect all money deposited by the players, which is also why they are fully responsible for the jackpot payout. Players will either receive the payout from the casino directly in their account or be allowed to withdraw it. 

Limited withdrawals

Most operators give players the payout in a single lump sum, no matter how high the jackpot. Some casinos make this a different process, however. Casinos with a less than reputable name might apply limits to the amount that can be withdrawn, which slows the process down unnecessarily. There are no real practical reasons for doing this, as it will always be simpler for a system to deduct a larger payout once than to deduct multiple smaller payouts every so often. These casinos often use this process to frustrate the player into accepting a smaller payout in a single lump sum, instead of the amount they actually won. This is something to watch out for when first reading the casino’s terms and conditions.

What exactly are videoslots?

Slot machines

Slot machines, also known as fruit machines or poker machines, are one of the mainstays of all casinos. Most people who are even vaguely familiar with gambling can recognize a slot machine when they encounter one. The machine usually has a screen that displays three or more reels that begin to “spin” when the game is activated. When slot machines were first invented, they were activated by pulling the large lever mounted on the side. Many modern slot machines still have a lever, though it is usually nothing more than a stylistic holdover. Most slot machines are nowadays operated using either buttons, a touchscreen, or a combination of both. The results are now decided by a random number generator, which enables more randomized results than the mechanical spring-based system the originals used.

Modern Casino Slot Machines Games


The advent of microprocessors allowed manufacturers to exert more control over the slots. They were now able to assign a different probability to every symbol. Players might think they missed the jackpot by a single slot rotation, but this isn’t necessarily true at all. The probability of acquiring a certain symbol does not have to be bound to what the machine displays visually. The machines with microprocessors first became common around the world in the 1980s. These machines had to conform to the new gambling legislation strictly, otherwise it might be suspected that they were altered to grant less favourable odds to the customers. Once a coin was inserted, there were two options. The coin could go directly into the owner’s cashbox, or it could go into the payout reservoir. The microprocessor monitored how full both reservoirs were at all times. The payout of the machine is directly proportional to the amount of money in the payout channel. If the channel was less full, the payout would be lesser as well. This allowed operators to remain in precise control of the odds and ensure a profit.

The development of the slot machine did not halt after the advent of microprocessors. A large number of slot machines are no longer mechanical at all nowadays. These virtual machines are called video slot machines. Video slot machines have fully digitized displays, which means they do not suffer any mechanical constraints. This fully digital system allowed this new type to branch out into the online sphere, with many new parties developing and marketing gambling websites. An example of the difference between mechanical and video slot machines is the fact that most video slot machines use a minimum of five reels. Mechanical machines nowadays almost always use three reels. The layout of the video slots might also be non-standard. The removal of the mechanical constraints allows for far more variety. The number of possibilities of a video slot machine can be far greater than those of a physical, mechanical machine. The odds could go up as high as 300 million to 1, which is higher than even the largest jackpots necessarily require. The manufacturers do not need to weigh the payout symbols, they may simply have the higher-paying symbols appear only once or twice instead. The digital displays further also allow the use of multimedia, often by including simple minigames as a bonus.

Video slot machines usually encourage the player to play multiple “lines”. The player does not need to take just the middle of the three symbols displayed on the reel. A line may also go from the bottom left to the top right. Machines will usually specify which patterns are allowed by the manufacturer. Each symbol is equally likely. As such the manufacturer can allow the player to take as many of the possible lines on offer as desired. The long-term return to the player will not change. The difference for the player is that the more lines they play, the more likely they are to receive a payout on any given spin. Manufacturers often offer bonus games, so the player does not simply feel as if they are slowly playing all their money away. Players are encouraged to keep playing until they reach the bonus game. The bonus game could allow them to win back their losses, and possibly more.

Random number generation

Every modern machine is outfitted with a random number generator. These generators would in actuality be called a pseudorandom number generator, but they are usually not referred to as such, as the term does not exactly inspire confidence in their randomness. They’re called this because the generated sequence is actually not truly random. A computer cannot generate a truly random number out of thin air, it requires human input to do so. The number is determined by an initial value, called the “seed”. This “seed” is determined when a player presses the button to play. The most recent random number in the programmed sequence will then be used to determine the result. The results are not truly random because they technically vary depending on when exactly the player presses the button. The result could be completely different if this button is pressed a fraction of a second earlier or later. Random number generators are still dependable since human perception would not be able to determine when to press the button for the best results. Sequences that are closer to truly random can be generated using hardware random number generators, but this would take far longer to generate the result. Pseudorandom number generators are more practical for the speed at which they generate the numbers, even if the results may not be truly random.

The fact that the results are not truly randomized could make it so that the slot machines are susceptible to cheating if a person has access to the algorithms used and is familiar with the seed values of the program. There are stories of casino programmers who used their knowledge to predict the outcome of the machines based on the previous results. The solution to this problem was surprisingly simple. Once this flaw in the design was discovered, the machines were modified to generate numbers even when the machine was not in use. Even players with knowledge of how the machine was programmed would not be able to predict the results, as they wouldn’t be able to tell where in the sequence they were.

The payout Structure of Videoslots


All machines have a pay table that will list the credits the player receives if the symbols line up. The table will show what the player would win for each combination of symbols and their current betting amount. Physical slot machines will usually list the pay table on the side or the face of the machine, but video slot machines will generally only display the pay lines that will result in the player winning a payout.

Slot machine categories

Slot machines in the United Kingdom can be categorized into multiple categories. These are the following:

Slot categoryMaximum stakeMaximum prize
ANo limitNo limit
B1£5£10,000£20,000 if the game has a progressive jackpot
B2£100 (divided in multiples of £10)£500
C£1£100£200 if the jackpot is repeated

Category A

Category A games exist only in theory. This category was defined in anticipation of the plan to establish large regional casinos in multiple parts of the United Kingdom. The plans for one such casino were proposed in 2007, but these were struck down by the House of Lords and entirely scrapped in 2008. There exist no lawful category A games in the United Kingdom.

Category B

Category B games can be subdivided into multiple categories:


Games of this category may only be made available in casinos.


Games of this category may only be made available in casinos, betting shops or at tracks with pool betting.


Games of this category may only be made available in casinos, betting shops, tracks with pool betting, bingo halls or adult gaming centres.


Games of this category may only be made available in casinos, betting shops, tracks with pool betting, bingo halls, adult gaming centres, members’ clubs, miners’ welfare clubs or commercial clubs.

Category C and D

This category encapsulates most low-stake slot machines in the United Kingdom, colloquially referred to as “fruit machines”, which are not located in a casino. Places such as pubs are automatically entitled to two gaming machines of either category C or D, as long as they notify their local licensing authority. Most of the machines in this category are not necessary slots, but machines such as coin pushers or crane grabs.

The jackpot

The term “jackpot” originates from the game Five Card Draw Poker. Players were only allowed to open the game if they were in possession of multiple Jacks or higher. A “pot” of “Jacks”, so to speak.

Many slot machines feature what is called a “progressive jackpot”. This means that the jackpot increases each time someone plays the game but does not win. The jackpot will increase until it is won, after which it will reset to the predetermined base value. The amount by which the jackpot advances will be manually set by the operator as a set percentage. Premises-based casinos will usually be outbid in this percentage, as they make more costs in general. Online casinos have less upkeep and general expenses to account for. Personnel is usually limited to management and programmers, while physical casinos need operating personnel, cleaners, security, etc.

The games in online casinos will regularly have a payout percentage of around 90% or higher, which is much rarer to find in physical casinos. These payout percentages differ per game, but the general way they function remains roughly the same. Imagine an online slot machine with a payout percentage of 90%. That means that the machine will return €90 in winnings for every €100 the player bets on average. This does not mean a player will win this every session. They might not even win it in a hundred sessions. The odds increase with every spin, which incentivizes players to keep spinning. A general rule is that slots with a better payout percentage have higher jackpots. 

Game variance

Another factor in the amounts paid out by a slot game is the variance. This refers to how often a game will pay out the jackpot as well as size of the payout. There are three general categories of variance:

Low variance

These games will pay out frequently, but almost never in large amounts.

Medium variance

These games pay out less frequently, but the prizes are a combination of smaller and larger payouts.

High variance

These games pay out very rarely. When these games do pay out, they pay out massively. 

Game variance is usually not advertised by the operator, but that does not mean it is impossible to find. Most well-known videoslots have been reviewed online. Even when they have not been formally reviewed, there are forums talking about these games. These are often independently hosted, but they might also be located on established forum platforms such as Reddit. A general rule to follow about variance is: the bigger the jackpot, the higher the variance.

When a game pays out often at a high percentage, it is referred to as “loose”. When a game is the opposite and pays out rarely with small amounts, it can be referred to as “tight”. Many casinos and websites will refer to their own games as “loose” in their advertisements.

Hit frequency

The last important factor to account for is the “hit frequency”. This percentage refers to the likelihood of a single spin resulting in a win for the player. It does not say anything about the amounts the player could win, only how often they will win instead of lose. If the hit frequency is 10%, the player will achieve a winning combination on average once every ten spins.