CasinoNieuws RTP study finds payout gaps of up to five points at Dutch casinos

A study by CasinoNieuws.nl found that the same online slot can carry different return-to-player (RTP) settings at legal Dutch casinos, with differences of up to five percentage points for some games. The research compared 40 popular slots from 10 game providers at 28 licensed online casinos between 6 and 8 October 2026. Bingoal ranked highest in the study, followed by 711 and Starcasino, while Fair Play Online, Tonybet and Lucky 7 Casino placed lowest.

CasinoNieuws.nl said operators can choose among several RTP levels that game developers make available for many slots, so the same game can have a higher theoretical payout at one casino than at another. The ranking was based on RTP steps: for each slot the researchers established how many levels the configured payout sat below the highest level available on the Dutch market, then calculated each casino's average deviation. A score of 0.00 means every studied slot offered by a casino was set at the highest available RTP level, and a higher score means an operator more often chose a lower payout. The ranking therefore reflects the average deviation from the highest available RTP level rather than the average payout of a casino's full game portfolio, and the number of slots studied differs by casino because not every operator offers all selected games.

Bingoal had the highest available payout level configured on all 24 slots it offers that were studied, giving it a score of 0.00, the best possible result. 711 scored 0.03, with 37 of 38 studied games at the highest RTP, and Starcasino also scored 0.03, with 34 of 35 slots at the highest level. Oranje Palace placed fourth with a score of 0.23, with 23 of 30 studied slots at the highest available payout. At the bottom, Fair Play Online Casino scored 1.24, Tonybet 1.35 and Lucky 7 Casino 1.37; at Fair Play Online Casino only one of the 33 studied slots was offered at the highest available payout. The results exclude ELK Studios, because no differences were found among that provider's slots.

The study gave examples of the gaps. Book of Dead from Play'n Go had a theoretical payout of 91.25% at one legal online casino, while four other legal online casinos offered the same game at an RTP of 96.21%. Starburst from NetEnt was offered by some operators at an RTP of 92.05%, while at other casinos the same slot had a theoretical payout of 96.09%. Differences were not equally large at every provider: among the studied Relax Gaming slots the researchers found two RTP levels, around 94% and 96%, while at Pragmatic Play most operators had set the studied slots at the lowest of the three available RTP levels.

All studied ELK Studios slots had the same payout of 94.00% at the Dutch online casinos, including Pirots 5, Grizzly Stampede, Tropicool 5 and Wild Toro III, and further ELK Studios slots examined by CasinoNieuws.nl also showed no differences between operators. The ELK Studios results were therefore left out of the calculation of the average RTP step deviation, though the games do count in the overview of the number of slots offered at the highest available RTP level. For the study, CasinoNieuws.nl selected 10 game providers based on their popularity on the Dutch market and examined four popular slots from each provider.

CasinoNieuws.nl said the full results of the RTP study, including the differences per game provider, are available on its page about the best-paying online casinos. The article was published on 21 October 2026 and was written by Jeffrey Noeken, a senior editor at CasinoNieuws.nl.