Borderline personality disorder (BPD) has been found to be closely linked to childhood trauma, particularly betrayal trauma. In our study, we aimed to investigate the association between betrayal trauma and anxiety among young adults. We assessed a total of 305 young adults using a Google form utilizing three assessment tools: the 10-item McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD), the 12-item Brief Betrayal Trauma Survey (BBTS), and the 7-item Generalized Anxiety Disorder (GAD-7) to evaluate borderline personality traits, betrayal trauma experiences, and anxiety level. Our findings revealed that 22% [95% confidence interval (CI) 17.7 to 26.9] of the participants screened positive for BPD on MSI-BPD assessment; self-reported anxiety as reported by GAD-7 was observed in 27.9% (95% CI 23.1 to 33.2), while 82% (95% CI 77.3 to 85.9) reported experiencing betrayal trauma. A significantly higher proportion of individuals with BPD (97%) reported experiencing betrayal trauma compared to those without the disorder. High betrayal trauma [odds ratio (OR) 8.14, 95% CI 3.06 to 21.67] and medium betrayal trauma (OR 7.06, 95% CI 2.64 to 18.92) were significantly associated with the diagnosis of BPD. The associations held true across genders, although they were stronger in females. Our study highlights the strong relationship between betrayal trauma and BPD, with significant implications for the development of anxiety in young adults. These findings underscore the importance of recognizing and addressing childhood trauma, particularly betrayal trauma, in individuals at risk for BPD.