The purpose of this study was to examine the effects of five UK-based harm prevention advertisements on gambling-related stigma. The researchers recruited 498 participants from Prolific. Participants had to be at least 18 years old, live in the UK, and have engaged with at least one non-lottery and non-bingo gambling format. Participants were shown five UK-based harm prevention advetisements and indicated their level of agreement about whether the advertisement could contribute to gambling stigma. Participants agreed that one advertisement, which focused on chasing losses, could contribute to gambling stigma. They did not agree that the other adverts would contribute to gambling stigma. Participants with higher problem gambling severity scores were more likely to provide higher perceived stigma responses for all advertisements. The researchers also analyzed qualitative optional feedback on the different types of advertisements that participants provided.