Across the Bettor-Verse: an Open Banking Perspective on Gambling in the United Kingdom.

Open banking provides an opportunity to leverage bank transaction data to support gambling harm prevention by providing an objective and comprehensive view of individuals' gambling activities. In this study, we present a large-scale descriptive analysis of gambling transaction activity from an open banking dataset, representing a sample of 1,030,788 users of a credit scoring service in the UK for 2022. The median gambler (n = 650,502) transacted with 2 merchants, made 14 deposits, had a typical debit of £10.00, a net loss of £95.00, and deposited 0.53% of income. Consistent with prior gambling literature, our analyses revealed small groups of gamblers (i.e., about 3%) who displayed disproportionately higher gambling activity based on their frequency of debits, total amount debited, and net loss. Males and younger people were more likely to fall into these high-involvement groups, and group members transacted with significantly more gambling merchants (5 to 6 merchants vs. the median of 2). This study establishes a baseline census of gambling activity from open banking data, offering insights to inform researchers and policymakers about opportunities for harm prevention.