Since the COVID-19 outbreak, people's habits changed radically. In fact, to limit the spread of SARS-CoV-2, governments implemented restrictive measures that influenced the lives of individuals. The aim of this systematic review is to analyze the impact of COVID-19 on gambling by examining three different outcomes: frequency, expenditure, and transition among possible types of gambling.

All studies assessing the impact of restrictive measures implemented to limit the spread of SARS-CoV-2 on gambling were included. For the search, two different databases were used: Pubmed and CINAHL.

Moreover, two different populations were analyzed: the general population, and subjects who used to gamble before SARS-CoV-2 pandemic. All qualitative studies, reports not based on peer-review, and papers in which the statistical unit was not the subject but the gambling or wagering operators were excluded.

From the search, 408 reports were identified. Of these, 28 were included in the systematic review. From the studies, a strong reduction in the frequency and expenditure of land-based gambling emerged, while the results about online gambling were different among the studies. However, a reduction was observed assessing sports betting, and an increase emerged considering online casino and skill games. Finally, a significant migration from land-based gambling to online platforms was identified. The main reasons for these findings were the physical closures of land-based gambling venues and the more time spent at home, the suspension or cancelation of sporting events on which subjects used to bet, and more mental health issues during this challenging period.

The COVID-19 pandemic greatly affected subjects' habits, including gambling, by reducing land-based gambling and sports betting, and increasing gambling on online platforms. This shift poses significant challenges, requiring a comprehensive approach to monitor and mitigate the negative consequences of this increase in online gambling caused by the pandemic.