In the context of the COVID-19 pandemic, personal protective measures (e.g., social distancing, handwashing, and mask wearing) have been adopted as a cornerstone to limit the spread of the disease. Yet, the effectiveness of these measures depends on people's levels of adherence. In this article, we apply social-psychological research to the study of compliance with personal protective measures during the COVID-19 pandemic in Chile. We consider three possible models underlying adherence: (1) sociodemographic and socioeconomic factors, (2) instrumental factors, and (3) normative factors. We draw on data from a longitudinal nonrepresentative panel study (Study 1, n = 32,304) and a cross-sectional representative survey (Study 2, n = 1,078) to explore the impact of these different factors on personal protective measures compliance. Findings show the strongest support for the role of instrumental and normative factors, in that people who comply with protective measures report to a greater extent that relatives and friends comply too and tend to perceive high risk of COVID-19. We finish by proposing policy recommendations to promote effective strategies to contain the spread of the virus.