Mental illness-related stigma acts as a critical barrier to care by fostering shame, fear of judgment and discrimination, which deters individuals from seeking help, delays treatment and worsens outcomes. This study aimed to investigate the forms, drivers and consequences of mental health-related stigma on help-seeking behavior. A cross-sectional study was conducted from November 2020 to March 2021. Data were collected from 419 participants using structured questionnaires, guided by the Health Stigma and Discrimination Framework and the Attitudes Towards Seeking Professional Psychological Help Scale for validation. Data were analyzed using Statistical Package for the Social Sciences version 22, employing descriptive statistics, chi-square tests and multinomial logistic regression. The average age of participants was 34.5 years. Findings revealed alarmingly high stigma: economic (76.8–80.2%), social (77.1–81.2%) and psychological (71.9–82.8%). Key drivers included stereotypes of dangerousness (58.7%) and systemic healthcare discrimination (65.6%). Multinomial regression confirmed that all stigma forms significantly reduced help-seeking odds. Structural barriers (odds ratio [OR] = 0.48) and internalized shame (OR = 0.53) were the strongest deterrents, with a multiplicative effect for combined economic and psychological stigma (OR = 0.41). This complex, multilayered barrier, driven by socio-cultural beliefs and structural failures, necessitates urgent, multifaceted interventions targeting public education, policy and self-stigma to improve mental health equity in rural Ghana.