Many players want to chase after the most rewarding slot games when they register at online casinos. The good news here is that there are plenty of slots that can provide decent rewards and the best way to recognize them is by looking at the highest payout rates.
The higher the RTP rate is, the better the overall returns will be. RTP stands for Return to Player percentage and it indicates the theoretical return of funds that players will receive over a longer period of time.
The volatility rate also plays a huge role – the higher the volatility of the slot is, the higher the jackpot payout will be. With that being said, we wanted to save you the hassle and provide you with the highest-paying video slots at online casinos.
Our first listing is the slot with the highest RTP in online casino history. Book of 99 is an online slot by Relax Gaming and as the name of the slot itself suggests, it comes with a 99% RTP.
This 5-reel title also has 10 fixed paylines on which you can form winning combinations and comes with an Ancient Egyptian theme.
Although many people label this release as a classic slot, Book of 99 slot machine has a couple of interesting bonus features. First off, we have the Wild symbol, which substitutes all regular symbols in the game. We also have the free spins mode which is triggered by landing at least 3 Wilds.
In this scenario, you will be provided with 10 free spins and a special expanding symbol. Next up, we have the Collection meter which is filled by landing Wilds. Once you land 99 Wilds on the reels, you will trigger the free spins mode.
320 Free Spins + €6000 Welcome Bonus.
18+ New Players Only. Min. Wagering Requirement. Valid until Further Notice. Full T&C's Apply
Next up, we have a legendary Thunderkick release – 1429 Uncharted Seas. This is a mid-century themed online slot in which you travel the seas in the quest for the biggest riches.
The RTP rate of 1429 Uncharted Seas is 98.6%, which is extremely high, indicating massive rewards. The layout of this game is 5×3 and there are 25 fixed paylines on which you can form winning combinations.
There are 8 regular symbols and in order to form a win, you need to land at least 3 matching symbols from left to right.
The Expanding Wild substitutes all regular symbols and will help you form winning combinations. It only expands when it is included in a winning payline. As for the Bonus Symbol, it is the key to triggering free spins. You will be happy to hear that you can receive up to 50 free spins and the rewards are the following:
Bets in 1429 Uncharted Seas can be set as low as $0.10 and as high as $100. The game is also fully optimized for mobile and desktop use.
100% up to $750 Welcome Bonus + 150 Free Spins
18+ New Players Only. Min. Wagering Requirement. Valid until Further Notice. Full T&C's Apply
The third pick on our list is by far the most rewarding slot of all time. Mega Moolah is responsible for several multi-million-dollar payouts throughout the years and the most recent one was in 2021 ($21.3 million).
This is a 5×3 slot by Microgaming which has 25 pay-lines. Unlike standard slots, Mega Moolah comes with a progressive jackpot with four levels.
Its RTP rate may be low as it is set at 88.12% and the jackpots contribute an additional 5.3%. To hit a winning combination here, you need to land at least 3 matching symbols and this African safari-theme online slot has one additional bonus feature as well – free spins.
They are triggered by landing at least 3 Scatters. Apart from being rewarded with cash, you’ll also be provided with 15 free spins and an x3 multiplier to your wins. Regular symbols in the game include various wild animals that you can come across in the African savannahs:
350% Match Bonus + 55 Free Spins
18+ New Players Only. Min. Wagering Requirement. Valid until Further Notice. Full T&C's Apply
Gladiator is an online slot developed by Playtech and just like Mega Moolah, it is well-known for its progressive jackpot. It has a 5×3 grid with 25 adjustable paylines.
The Gladiator Jackpot Bonus is triggered by landing 3 Wild symbols on the reels. During this bonus round, you will be provided with 9 random helmets, which are either bronze, silver or gold. If you land 9 gold helmets, then you will win the progressive jackpot.
A free spins mode called the Colosseum bonus is also featured and it is triggered by landing at least 3 Scatters on the reels. Once you trigger the mode, you will have 4 options:
Gladiator features 11 regular symbols: 9, 10, J, Q, K, A, Juba, Proximo, Gracchus, Lucilla and Commodus.
200% up to €500 Bonus + 100 Free Spins
18+ New Players Only. Min. Wagering Requirement. Valid until Further Notice. Full T&C's Apply
Our final pick on the list is Cleopatra, an Ancient Egypt-themed online slot by IGT. The maximum jackpot exposure of this online slot is 10,000x the stake and thanks to the Cleopatra Bonus feature, you can receive up to 180 free spins, which is truly unbelievable.
Cleopatra’s bet limits go from as low as $0.20 to as high as $600. There are 20 featured paylines on which you can form winning combinations and its RTP rate is 95.02%. Regular symbols here include:
Apart from the regular symbols, we also have the Cleopatra Wild and the Sphinx Scatter. The Cleopatra bonus starts with 15 free spins but since it can be re-triggered, you can win up to 180 free spins. Multipliers are also present during this feature.
150 Free Spins + €2400 Casino Bonus
18+ New Players Only. Min. Wagering Requirement. Valid until Further Notice. Full T&C's Apply
The RTP signifies the returns that players you will receive in a longer period and they definitely play a role in the most rewarding slots. The math here is simple – the higher the RTP rate is, the more rewarding the slot is.
Mega Moolah holds the record for the biggest jackpot payout in history. Not only that, but this online slot by Microgaming is responsible for most of the 10 biggest online jackpot payouts. That’s the reason why all high-rollers consider this title as their favourite.
To play any of the aforementioned online slots for real money, you will have to find a licensed and reputable online casino where these games are featured. Click on the register button, fill in the required fields and accept the T&Cs. The process won’t take more than a minute and once you verify your account, you will be able to withdraw all of your winnings.
Cleopatra is known for the fact that it can reward players with up to 180 free spins. In order to trigger this feature, you will have to land 3-5 Sphinx Scatters on the reels. At first, you will be provided with 15 free spins and the best part about them is that a win multiplier is also present.
As a progressive slot, Mega Moolah comes with a high volatility rate. That means that its maximum jackpot exposure is extremely high, but it does not drop very often. In fact, the progressive jackpot is triggered quite rarely.