Lower-risk Gambling Guidelines (LRGGs) were developed in Canada to reduce the risk of gambling-related harm. The LRGGs, published in 2021, consist of three limits: gamble no more than 1% of household income per month; gamble no more than four days per month; and avoid regularly gambling at more than two types of games. All three limits should be followed at the same time. This study focuses on the situation in Finland before the LRGGs were published. The aim of this study is to investigate trends in lower-risk gambling by age and net income among men and women in the Finnish adult population in 2011, 2015, and 2019. Data were drawn from cross-sectional Finnish Gambling population surveys, including permanent residents in Mainland Finland aged 15–74 with Finnish, Swedish or Sámi as their mother tongue (2011; n = 4,484, 2015; n = 4,515, and 2019; n = 3,994). The results showed an increase in the prevalence of lower-risk gambling, rising from 29% in 2011 to 39% in 2019. This upward trend was observed among both men and women, with the prevalence among men increasing from 23 to 33%, and among women from 34 to 45%. The lowest prevalence of lower-risk gambling was found among individuals aged 60–74, especially regarding expenditure guidelines, as well as among women in the lowest income tertile. In conclusion, although the prevalence of lower-risk gambling has increased in Finland, there is still potential for further improvement to minimize harm.