The integrated behavioural health care (IBHC) model incorporates mental health services with primary care. This service model is widely advocated due to its increasing access to health care and cost-saving. By connecting individuals with mental illnesses with a primary care provider, this model of care promotes collaboration between interdisciplinary teams, and therefore, increases health equity, decreases stigma, and increases patient satisfaction. This integrative review aimed to examine and synthesize available literature on facilitators and barriers related to the IBHC model implementation in the United States. An integrative review methodology by Whittemore and Knafl was utilized, and data evaluation was based on the JBI Critical Appraisal Checklist. The social-ecological model guided the review. Twenty-two articles were analysed, and nine themes were identified, which were further organized according to the five levels of the social-ecological model and consisted of intrapersonal level – patient-centered care; interpersonal level – relationships; community level – physical accessibility; organizational level – operation and infrastructure, team approach, training in behavioural health, electronic medical record, and staffing; and policy level – funds and health insurance. Most facilitating factors were on the organizational level and related to infrastructure, team approach, patient-centered care, and the most noted barrier was poor relationships. Nurses can increase engagement in integrated care by assuming roles that oversee patient care, foster professional collaborations, and improve relationships. Future research should focus on vulnerable populations this model serves, patients’ perspectives, and the effect of telehealth.