It remains unclear if gambling advertising and promotion increase demand for, and consumption of, gambling, or only affect market share distributions without increasing total consumption. Although this has been investigated in relation to land-based gambling, studies have not examined how such marketing influences behavioural patterns of Internet gamblers. The aim of this study, therefore, was to explore ways in which advertising and promotion of Internet gambling may contribute to increased consumption of gambling. Qualitative interviews were conducted with 50 Internet gamblers drawn from the general population, and 31 treatment-seeking Internet gamblers. In-depth analysis of interview transcripts revealed limited reported effectiveness of advertising and promotions in converting non-gamblers to Internet gamblers. However, general population gamblers reported occasionally gambling more than intended (increased consumption) in response to free bet and deposit offers. A proportion of treatment-seekers reported increased gambling, particularly associated with bonus offers that required matched deposits and gambling before any winnings could be collected. Advertisements and promotions invoked urges to gamble among treatment-seeking gamblers, and appeared to some participants to be designed to target individuals who had taken steps to limit or cease gambling. Findings provide preliminary evidence of Internet gambling promotional activities increasing overall consumption amongst a subgroup of gamblers.