Introduction: Many primary care clinics screen patients for their unmet social needs, such as food insecurity and housing instability, and refer them to community-based organizations (CBOs). However, the ability for patients to have their needs met is difficult to evaluate and address. This study explores patient-reported barriers to accessing referred resources using a conceptual framework that identifies opportunities for intervening to optimize success.Methods: Patients who participated in a social needs screening and referral intervention at a Federally Qualified Health Center (FQHC) were called 2 weeks after the clinic encounter. We conducted a directed content analysis across 6 domains of access to examine responses from patients who reported barriers.Results: Of the 462 patients that were reached for follow-up, 366 patients reported 537 total barriers. The most frequent challenges related to resource availability (24.6%, eg, patients waiting for submitted application to process) and approachability (23.8%, eg, patients lacking information needed to contact or access resources). Barriers in the domains of acceptability (21.6%, eg, competing life priorities such as medical issues, major life events, or caretaking responsibilities) and appropriateness (17.9%, eg, resource no longer needed) largely represented patient constraints expressed only after the clinical encounter. It was less common for patients to identify accommodation (eg, physical limitations, language barriers, transportation barriers, administrative complexity) or affordability of community resources as barriers (11.2% and 0.9%, respectively).Conclusion: Findings suggest opportunities for improvement across the access continuum, from initial referrals from primary care staff during the clinical encounter to patients' attempts to accessing services in the community. Future efforts should consider increased collaboration between health and social service organizations, and advocacy for structural changes that mitigate system-level barriers related to resource availability and administrative complexity.