Not all online casinos are created equal
A new Jackpot.win analysis comparing the average Return to Player (RTP) percentages across ten major online casino operators has uncovered significant differences in the mathematical value offered to players.
The study examined some of the most popular slot games currently enjoyed by casino enthusiasts and compared the RTP settings available across competing operators. The results show that while many casinos offer exactly the same games, the underlying mathematics can vary dramatically depending on where players choose to play.
Coolbet Emerges as Standout Performer
Among the operators analysed, Coolbet emerged as the standout performer with an average RTP of 96.31%. UnionBet ranked second on 95.98%, while GOATZ secured third place with 95.88%.
Coolbet’s margin of 0.33 percentage points over its nearest challenger may appear modest, but as RTP differences compound across millions of spins, even fractions of a percentage point can translate into substantial additional returns to players.
At the opposite end of the rankings, Casino Friday recorded an average RTP of 94.03%, more than two percentage points behind the market leader.
Average RTP Rankings
| Rank | Operator | Average RTP |
|---|---|---|
| 1 | Coolbet | 96.31% |
| 2 | UnionBet | 95.98% |
| 3 | GOATZ | 95.88% |
| 4 | Norsk Tipping | 95.40% |
| 5 | ComeOn! | 94.94% |
| 6 | Unibet | 94.80% |
| 7 | Epicbet | 94.65% |
| 8 | Respin | 94.65% |
| 9 | Betsson | 94.63% |
| 10 | Casino Friday | 94.03% |
The difference between the highest and lowest-ranked operator may appear modest at first glance. However, as Jackpot.win previously demonstrated in its analysis of the RTP gap, even seemingly small differences can translate into enormous sums over time as millions of spins are played across thousands of customers.
Same Slots, Different Mathematics
One of the most striking findings from the study is that many operators offer identical slot titles while using entirely different RTP configurations. Modern slot releases are frequently supplied to operators with multiple RTP versions. Casinos can therefore choose which mathematical model they wish to offer their customers.
As a result, two players can be spinning the same game from the same provider at the same stake level while facing significantly different long-term probabilities. Most players remain unaware of this practice, focusing instead on promotions, bonuses and free-spin campaigns. Yet RTP remains one of the most important indicators of value available to players.
The Slots Included In The Comparison
To ensure a fair comparison, Jackpot.win analysed a selection of popular slot games from leading providers including Pragmatic Play, Hacksaw Gaming, ELK Studios, Relax Gaming, Play’n GO and others.The slots included in the study were:
- Gates of Olympus Super Scatter
- Sugar Rush 1000
- Gates of Olympus 1000
- Gates of Olympus
- Sweet Bonanza 1000
- Le Bandit
- Pirots 4
- Wanted Dead or a Wild
- Linko 5
- Sweet Bonanza
- Mystery Joker
- Starburst
- Jackpot 6000
- Sweet Rush Bonanza
- Book of Dead
- Sugar Rush Super Scatter
- Legacy of Dead
- Le Fisherman
- Pirots 3
- Moon Princess: 100
- Fruit Party
- Duck Hunters
- Smoking Dragon
- Duck Hunters Happy Hour
The operators compared were Coolbet, UnionBet, GOATZ, Norsk Tipping, ComeOn!, Unibet, Epicbet, Respin, Betsson and Casino Friday. Where a slot was unavailable at a particular operator, it was excluded from that operator’s average RTP calculation.
The Biggest RTP Differences
Several individual games displayed remarkable RTP discrepancies between operators.
In some cases, players were offered versions of the same slot with dramatically different mathematical returns, despite the gameplay experience appearing identical.
| Slot | Highest RTP | Lowest RTP | Difference |
|---|---|---|---|
| Mystery Joker | 96.98% | 90.98% | 6.00% |
| Book of Dead | 96.21% | 91.25% | 4.96% |
| Legacy of Dead | 96.58% | 91.51% | 5.07% |
| Moon Princess: 100 | 96.20% | 91.20% | 5.00% |
| Le Bandit | 96.40% | 92.29% | 4.11% |
| Gates of Olympus 1000 | 96.50% | 94.03% | 2.47% |
| Wanted Dead or a Wild | 96.43% | 94.59% | 1.84% |
The most dramatic example was Mystery Joker, where the RTP ranged from 90.98% to 96.98% depending on the operator. That’s a six-percentage-point difference in the mathematical return offered to players despite the game itself appearing identical.
Other popular titles such as Book of Dead, Legacy of Dead and Moon Princess: 100 also showed RTP variations of around five percentage points, underlining the importance of checking not only which slot is being played, but also where it is being played.
RTP Is Only Part Of The Story
While RTP remains one of the most important measures of player value, the study revealed another noteworthy trend. Several operators offered significantly smaller slot catalogues than their competitors.
For enthusiasts who regularly play new releases, explore niche providers or follow the latest industry launches, game availability can be almost as important as RTP itself.
A casino may offer strong RTP settings, but if the catalogue is limited, players inevitably have fewer choices.
Conversely, some operators combine competitive RTP settings with extensive game libraries, giving players access to both stronger mathematics and greater variety. The ideal combination is clear: high RTP and broad game selection.
Greater Transparency Benefits Players
The findings underline why RTP transparency remains so important within the online casino industry. Players routinely compare welcome bonuses, loyalty schemes and promotional offers before opening an account. Far fewer compare RTP settings, despite RTP having a direct impact on the value of every spin.
This analysis demonstrates that where players choose to play can be just as important as which games they choose to play.
The slots may look identical.
The reels may spin the same way.
The bonus features may remain unchanged.
The mathematics, however, can tell a very different story.