Biosimilars are essential for improving healthcare access and sustainability; however, their adoption is strongly influenced by the public perception, knowledge, and trust. The curremt study aimed to comprehensively evaluate awareness, trust, acceptance, and related beliefs toward biosimilars among the general public in Saudi Arabia. A cross-sectional survey was conducted by the use of a structured bilingual questionnaire (35 items). Data from 512 participants were analyzed using descriptive statistics and regression analysis. Awareness of biologics was 68.4%, whereas awareness of biosimilars was significantly lower (38.7%). Misconceptions were prevalent, particularly regarding equivalence and safety. Trust was highest in physicians (76.3%) and pharmacists (71.5%). Acceptance of biosimilars was moderate, with 61.7% willing to initiate treatment and 53.2% accepting switching. Concerns were reported by nearly half of the respondents. Public perception of biosimilars is shaped by knowledge gaps, trust, and psychological factors. Targeted educational strategies are necessary to improve acceptance and support healthcare sustainability.
