Treatment access for those with trichotillomania is limited by several issues including professionals’ lack of knowledge of the disorder, proximity to providers, and financial constraints. Acceptance-enhanced behavioral therapy (AEBT) has been implemented in groups and using telehealth to reach a larger population. However, these methods still require therapist time and incur notable costs. This study aimed to address the gap in trichotillomania treatment accessibility by examining the feasibility and efficacy of a self-guided, web-based AEBT treatment for adults with trichotillomania across the United States. Participants completed an eight-module asynchronous program over eight weeks. The effects of the website were tested with 81 adults with trichotillomania randomized into a treatment and waitlist condition. Results demonstrated statistically stronger decreases in the treatment condition over the waitlist condition across outcomes including trichotillomania symptoms severity, trichotillomania-related psychological flexibility, well-being, total distress, depression, and stress. Treatment effects were maintained at one month follow-up. Anxiety did not significantly decrease between conditions, but a significant decrease was found across time. Of participants in the treatment condition, 52.8% (vs 15% for waitlist) met treatment responder status from pre-to post-treatment and 30.5% (vs 10% for waitlist) met responder status from pre-treatment to follow-up. Implications of these preliminary findings are discussed.