Previous research shows that crises can produce both negative and positive mental health effects. The current study explored these effects in context of the COVID-19 pandemic. An online survey was administered among a representative sample of the Dutch population (n = 1519) in June 2020, when the peak of COVID-19 cases was ten weeks past. Participants were asked about mental health, adverse events during COVID-19, and about any positive effects of the pandemic. Most participants (80%, n = 1207) reported no change in mental health since the COVID-19 pandemic. This was also the case among respondents who had experienced an adverse event. Protective factors of mental health were being male and high levels of positive mental well-being. Risk factors were emotional loneliness and the experience of adverse life events. Unexpected, social loneliness was also positively associated with stable mental health, perhaps suggesting that people are okay with seeing less people, as long as meaningful relationships can be maintained. 58% of participants reported positive effects of the pandemic, the most common of which were rest, working from home, and feeling more socially connected. In summary, most people remained stable during the crisis, and where even able to report positive effects.