Biggest Progressive Jackpots

Written by Dean McHugh
Dean McHugh
Dean McHugh is a full-time writer with more than 20 years of experience in the iGaming industry. Specialising in casino reviews, slot analyses, and sportsbook evaluations, he delivers clear, engaging, and insightful content for both industry professionals and casual players. Over the past four years, he has contributed extensively to leading iGaming comparison websites.
, | Updated: Fri 29 August 2025

Slots are among the most sought-after games in both online and land-based casinos. However, one group of online slots attracts the greatest number of players, namely the titles that are linked to progressive jackpots. As a matter of fact, the lives of many lucky players have been completely changed by winning one of these jackpots.

The adjective “progressive” is itself suggestive, as slots that fall within this category are linked to a progressive jackpot network across multiple online casinos, and the jackpot amount continues to increase incrementally each time a player places a bet and presses the Spin button. This allows the prize to grow to astronomical sums that often reach millions of pounds.

The jackpot is awarded at random, and as soon as one lucky player scoops the colossal prize, it starts accumulating all over again. However, this accumulation does not start from scratch but from a predetermined amount called a seed. Players can keep track of the current value of the jackpot on the jackpot metre that is often positioned above the title of the progressive slot.

There are several things players need to take into consideration before they put their luck to the test at progressive slots. Please note that, in many cases, players are required to place the maximum bet in order to become eligible to win the massive progressive prize. If you fail to do so, you will not get paid even if you are lucky enough to land the winning combination that triggers the jackpot. Thus, slot fans are required to play the maximum number of coins, the highest coin value, and all available paylines, or some combination of the three, because a small percentage of each bet goes towards the jackpot pool.

Another thing to take into account is the volatility of progressive slots. Slots with astronomical jackpots attached to them are often said to have high volatility, which means that they tend to award regular wins less frequently.

Finally, players should bear in mind that progressive jackpots do not become “due” simply because no one has collected the massive prize in a long time. Your chances of winning the progressive prize remain the same regardless of how large the jackpot has grown.

Online Slots with the Biggest Progressive Jackpots

All established online casino operators have added slots with progressive jackpots to their gaming collections. Usually, the titles that offer the most lucrative prizes are put in a prominent place on an online casino’s website and are accompanied by vivid banners to draw the attention of players. To make things easier for players, we have compiled a list of five popular online slots that offer the largest progressive jackpots.

Mega Moolah

Mega Moolah has not earned the title of a ‘millionaire maker’ for nothing. This five-reel, 25-payline slot, developed by leading software supplier Microgaming, even made it into Guinness World Records in 2015, when one lucky player collected the colossal sum of £13,209,300, which remains the largest jackpot payout in an online slot game to this day.

Apart from the huge progressive prize, Mega Moolah comes with a fun and enjoyable theme. The game was inspired by the African savannah and employs monkeys, elephants, lions, giraffes and buffaloes as symbols. Players get the chance to scoop the jackpot anytime and anywhere, as Mega Moolah has been adapted for smartphones and tablets running on iOS and Android. In addition, Mega Moolah is packed with great features including wild and scatter symbols, rounds of free spins, and, most importantly, a jackpot bonus game that is triggered at random.

Biggest Progressive Jackpots – Microgaming’s Mega Moolah

The jackpot bonus game features a wheel divided into coloured sectors, each colour corresponding to one of the four jackpots Mega Moolah has to offer, namely the Mini, Minor, Major and Mega Jackpots. Of course, the wheel contains more sectors for the Mini and Minor Jackpots, which are won more frequently.

Players are expected to spin the wheel and wait for it to come to rest so that the jackpot selector can determine which of the four jackpots has been won. Players’ chances of triggering the bonus jackpot game grow proportionately to the size of their wagers. Thus, the larger your bets per spin, the greater your chances of activating the bonus wheel game. With a jackpot seed of £1 million and a 75,000-coin jackpot in its base game, Mega Moolah is definitely worth your time.

Microgaming’s Mega Moolah Jackpot Game

Jackpot Giant

Courtesy of well-known software developer Playtech, Jackpot Giant is among the most popular online slots offering a progressive jackpot. The game is played on the standard five reels and offers a total of 50 paylines. Jackpot Giant is a beautifully designed online slot that takes players back to the caveman era and impresses with rich graphics, great animations and engaging sound effects.

Biggest Progressive Jackpots – Playtech’s Jackpot Giant

Apart from its stunning design and visuals, Jackpot Giant is packed with great features that aim to make players’ gaming experience more rewarding and entertaining. For instance, whenever players land the bonus symbols on the first or fifth reel, they will unlock a fun bonus game in which they must select three of six volcanoes to collect a cash prize. It is also possible to be awarded an additional fourth pick, or even collect all prizes, if you click on the “Win ‘em All” volcano.

Yet, the biggest attraction of Jackpot Giant is the astronomical progressive jackpot it offers. This colossal prize is triggered at random, but players are required to bet the maximum amount available in order to qualify. To trigger the jackpot, one needs to land five identical wild symbols on the first payline that runs straight across the middle of all five reels. Players can conveniently track the progress of the jackpot by checking the jackpot metre positioned at the top of the game’s screen. The progressive prize usually reaches a seven-figure sum, so you can rest assured Jackpot Giant is definitely worth a spin or two.

Playtech’s Jackpot Giant Jackpot Game

Mega Fortune

Mega Fortune is among the most popular progressive slots you can play online. This is hardly surprising, because the game has been created by respected gambling software developer NetEnt, which guarantees players a hassle-free experience, superb graphics and compelling sound effects that will surely hold their attention for a long time.

The theme of the game revolves around the luxurious lifestyle enjoyed by the wealthy, as becomes evident from the symbols NetEnt has used for the reels. These include jewel-studded watches, limousines, wads of banknotes and bottles of champagne. Other than that, the game employs the standard five-reel format and offers 25 paylines, as well as rounds of free spins with multipliers, scatters and wild symbols.

Biggest Progressive Jackpots – NetEnt’s Mega Fortune

Of course, Mega Fortune’s biggest attraction is the progressive jackpot it offers, with an expected value averaging 4 million credits. Apart from this massive pooled Mega Jackpot, Mega Fortune features two smaller, local jackpots, namely the Major and Rapid Jackpots. These two jackpots are called local because their amounts are determined by players who bet on Mega Fortune at any particular casino that offers the game. Because of this, the size of these two jackpots can vary greatly from one online casino to another.

Needless to say, it is the Mega Jackpot all players are after, as it often reaches millions of pounds thanks to being pooled across all online casinos that offer the Mega Fortune slot. To try to win the Mega Jackpot, players are expected to unlock the jackpot bonus game by landing three bonus symbols on an active payline. The game features a wheel which, when spun, will reward players with one of the three jackpots or a coin prize. It is also possible to win a round of free spins with multipliers of up to 5x on your winnings.

NetEnt’s Mega Fortune Wheel Jackpot Game

Marvel Progressive Slots

The online slots from Playtech’s Marvel-branded series are among the most popular titles at web-based casinos. This immense popularity is entirely justified, first and foremost, because each Marvel-branded slot comes with a stunning design, vivid graphics and fascinating animations. Some of the titles even feature footage from the popular superhero films that play when winning combinations are spun on the reels.

It matters not who your favourite superhero is – there is a good chance you will find a slot to suit your preferences, as Playtech has created titles that feature some of the most well-known characters inhabiting the Marvel Universe. These include Spider-Man, the Incredible Hulk, Iron Man, Blade, the Avengers, Thor, Wolverine, the Fantastic Four, Daredevil and Captain America, among others. Some of these titles have two versions – one with 25 paylines and the other with 50 lines.

Biggest Progressive Jackpots – Playtech’s Marvel Slot Elektra

All of these titles are linked to Playtech’s Marvel Progressive Jackpot Network and contribute to the pool. It matters not which Marvel-branded slot you decide to go for – you still have a chance of winning the colossal prize. What is more, each Marvel slot offers four different jackpots, namely the Power, Extra Power, Super Power and Ultimate Power prizes.

The jackpot is triggered at random and there is no particular symbol combination that results in players unlocking the prize. Nevertheless, it is recommended to bet the maximum amount, as this will increase your chances of winning the jackpot.

Once the jackpot is triggered, players will enter a bonus mini-game that guarantees them one of the four progressive prizes. The bonus game features a grid with twenty squares that are facedown. Players are expected to click on the squares to flip them over and find three identical symbols, as this determines which of the four prizes they will be awarded. Please note that there is a time-out timer, so if you fail to flip the squares over within the designated time, you will be awarded one of the four prizes automatically.

Playtech’s Marvel Slots Jackpot Game

Monty Python’s Spamalot

Playtech’s Monty Python’s Spamalot is based on the popular British surreal comedy show and, in particular, the film Monty Python and the Holy Grail. The game is played on five reels and has a total of 20 paylines to offer. Its special features include wild and scatter symbols as well as four bonus games – Storm the Castle, The Incredibly Brave Knight, The Knights Who Say Ni and The Killer Rabbit.

Yet, what slot fans crave the most is triggering the Jackpot Game that will provide them with an opportunity to win one of two progressive prizes, namely the Holy Grail Jackpot and the Slightly Less Holy Grail Jackpot. As you can see, Playtech has succeeded in retaining some of the quirky humour the British show is known for.

Biggest Progressive Jackpots – Playtech’s Monty Python’s Spamalot

Players need to go through several steps if they wish to unlock the bonus game that can earn them the coveted jackpot. First, you must trigger a round of 10 free spins by landing three or more Monty Python scatter symbols on the reels. If you hit five symbols reading “Jackpot Game” during the round of free spins, you trigger the jackpot bonus game, which spans six levels.

Players are required to climb to the sixth level and pick one of the two symbols presented to them. Those who select the lucky symbol will win one of the two jackpots available. It is the Slightly Less Holy Grail Jackpot that is won more frequently, as it roughly amounts to £1,000. In comparison, the “slightly” larger Holy Grail Jackpot typically exceeds £1.2 million.

Playtech’s Monty Python’s Spamalot Jackpot Game