The present paper reviews recent studies on problematic Internet use (PIU) prevalence before and during the coronavirus disease 2019 (COVID-19) pandemic. Several pre-pandemic meta-analyses reported PIU prevalence estimates ranging from 6% to 9.7%. Experts in the field of online addictions speculated that PIU would increase during the pandemic because of increased time spent on the Internet. However, it is still unclear if increased time on the Internet resulted in higher PIU prevalence estimates during the pandemic. Prevalence estimates differed greatly across studies during the COVID-19 pandemic. Possible inconsistencies are outlined together with future directions for PIU prevalence studies.