Aims: Both gambling and digital gaming are growing in popularity and there is ongoing discussion about their convergence. This population-based longitudinal survey study investigated how gambling and digital gaming types contribute to at-risk gambling and gaming. Methods: The study was based on a representative sample of 18–75-year-olds from mainland Finland. Survey data were collected at 6-month intervals in 2021–2022, starting in April 2021. Of original T1 respondents, 58.95% took part in all four time points. In total, 3,608 observations from 902 individuals were analysed. Outcome measures were at-risk gambling and gaming based on the Problem Gambling Severity Index and the Internet Gaming Disorder Test. Various types of gambling and gaming were investigated. Results: Population-averaged models showed that different forms of gambling were associated with a higher risk of at-risk gaming. Online casino games were associated with the highest likelihood of at-risk gambling and gaming. Prevalence of digital gaming problems was low. Hybrid models were used to investigate the longitudinal within-person and between-person effects of gambling and gaming activities. Online casino games and offline slot machines increased at-risk gambling. Microtransactions within digital games increased at-risk gambling and gaming over time, but the amount of money spent on digital gaming was small compared to gambling. Conclusions: Our results underline the risks of EGMs and online gambling for the participants. Although gambling and gaming are converging, harm is mostly based on gambling.