“When the fun stops, stop” was a popular safer gambling message seen in the UK from 2014 until at least October of 2021. The researchers did three online experiments to test the impact of this message. Participants were offered real money to gamble on football matches (experiments 1 and 3) or an online roulette game (experiment 2). Each experiment randomly assigned participants to see the original yellow version of the message or no message. Experiment 2 included an extra condition in which participants saw a black and white version of the message. The results across the experiments showed that the message had no beneficial effect in reducing gambling behaviours.