Teeth bleaching is more popular in Saudi Arabia. The purpose of the present study was to assess the knowledge of at-home and In-office teeth bleaching and its adverse effects among the general population of Saudi Arabia. This cross-sectional study used a structured, close-ended, self-administered and pretested online questionnaire to record the responses. Descriptive statistics, Chi-square, and Fisher's exact tests were applied to the data. Results showed that the participants in this study were 2065 people. The number of male and female respondents was 45.6% and 54.4%, respectively. Tea, coffee, smoking/tobacco, and shisha were mentioned by 88.2% of the study participants as all causes of teeth staining. 99.3% of the study participants had prior knowledge of teeth bleaching. Nearly 61.5% and 62.2% of study participants were aware of the adverse effects of home-based and dentist-supervised bleaching products. The knowledge of teeth bleaching and its adverse effects differed significantly across this study's demographic factors. This study showed adequate knowledge of teeth discoloration, bleaching protocols, and adverse effects. However, most study participants favored in-office bleaching rather than at-home bleaching.
